From patchwork Thu Mar 26 15:56:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: develop--- via Libc-alpha X-Patchwork-Id: 1262087 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=8.43.85.97; helo=sourceware.org; envelope-from=libc-alpha-bounces@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=sourceware.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=NPF8+E+p; dkim-atps=neutral Received: from sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 48p8kd6mXQz9sRY for ; Fri, 27 Mar 2020 02:57:13 +1100 (AEDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 7A72A385E006; Thu, 26 Mar 2020 15:57:03 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 7A72A385E006 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1585238223; bh=Fp2AHCy0+97vg1rcxvyEfg1BioJoFhRu5gctPR8gewI=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=NPF8+E+pzUP7SO6crRnNbu/aTlGM2/tH6SU1ciO62KrmYsf4GELk9kp+Fvfhm/g+i GBf4v9xG1lpeE0O0SWqQFjY3XF+1Xe++YqpN3LNatJpGMLCws14gjC4+6YKeDtFO9E dMiFaT6Y30VsQ4X++DyHJN0CglXOp3dGhjFMbO9E= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail.efficios.com (mail.efficios.com [167.114.26.124]) by sourceware.org (Postfix) with ESMTPS id 1A80D385E009 for ; Thu, 26 Mar 2020 15:56:58 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 1A80D385E009 Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id BEC192777DC; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id UAvscK-pvJDP; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 40A572777D9; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 40A572777D9 X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id YtxQLU5iOnp1; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) Received: from localhost.localdomain (192-222-181-218.qc.cable.ebox.net [192.222.181.218]) by mail.efficios.com (Postfix) with ESMTPSA id 0D96B2772C1; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) To: Carlos O'Donell Subject: [PATCH glibc 1/9] Introduce Date: Thu, 26 Mar 2020 11:56:25 -0400 Message-Id: <20200326155633.18236-2-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> References: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> X-Spam-Status: No, score=-29.2 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, KAM_STOCKGEN, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mathieu Desnoyers via Libc-alpha From: develop--- via Libc-alpha Reply-To: Mathieu Desnoyers Cc: libc-alpha@sourceware.org, Joseph Myers Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" From: Florian Weimer MIPS needs to ignore certain existing symbols during symbol lookup. The old scheme uses the ELF_MACHINE_SYM_NO_MATCH macro, with an inline function, within its own header, with a sysdeps override for MIPS. This allows re-use of the function from another file (without having to include or providing the default definition for ELF_MACHINE_SYM_NO_MATCH). Built with build-many-glibcs.py, with manual verification that sysdeps/mips/elf_machine_sym_no_match.h is picked up on MIPS. Tested on aarch64-linux-gnu, i686-linux-gnu, powerpc64-linux-gnu, s390x-linux-gnu, x86_64-linux-gnu. Reviewed-by: Carlos O'Donell --- elf/dl-lookup.c | 10 ++---- elf/elf_machine_sym_no_match.h | 34 +++++++++++++++++++ sysdeps/mips/dl-machine.h | 15 --------- sysdeps/mips/elf_machine_sym_no_match.h | 43 +++++++++++++++++++++++++ 4 files changed, 79 insertions(+), 23 deletions(-) create mode 100644 elf/elf_machine_sym_no_match.h create mode 100644 sysdeps/mips/elf_machine_sym_no_match.h diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c index 12a229f06c..807f3ea9b6 100644 --- a/elf/dl-lookup.c +++ b/elf/dl-lookup.c @@ -28,18 +28,12 @@ #include #include #include +#include #include -/* Return nonzero if check_match should consider SYM to fail to match a - symbol reference for some machine-specific reason. */ -#ifndef ELF_MACHINE_SYM_NO_MATCH -# define ELF_MACHINE_SYM_NO_MATCH(sym) 0 -#endif - #define VERSTAG(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (tag)) - struct sym_val { const ElfW(Sym) *s; @@ -78,7 +72,7 @@ check_match (const char *const undef_name, if (__glibc_unlikely ((sym->st_value == 0 /* No value. */ && sym->st_shndx != SHN_ABS && stt != STT_TLS) - || ELF_MACHINE_SYM_NO_MATCH (sym) + || elf_machine_sym_no_match (sym) || (type_class & (sym->st_shndx == SHN_UNDEF)))) return NULL; diff --git a/elf/elf_machine_sym_no_match.h b/elf/elf_machine_sym_no_match.h new file mode 100644 index 0000000000..6e299e5ee8 --- /dev/null +++ b/elf/elf_machine_sym_no_match.h @@ -0,0 +1,34 @@ +/* Function to ignore certain symbol matches for machine-specific reasons. + Copyright (C) 2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _ELF_MACHINE_SYM_NO_MATCH_H +#define _ELF_MACHINE_SYM_NO_MATCH_H + +#include +#include + +/* This can be customized to ignore certain symbols during lookup in + case there are machine-specific rules to disregard some + symbols. */ +static inline bool +elf_machine_sym_no_match (const ElfW(Sym) *sym) +{ + return false; +} + +#endif /* _ELF_MACHINE_SYM_NO_MATCH_H */ diff --git a/sysdeps/mips/dl-machine.h b/sysdeps/mips/dl-machine.h index 06021ea9ab..e3b11a4f21 100644 --- a/sysdeps/mips/dl-machine.h +++ b/sysdeps/mips/dl-machine.h @@ -467,21 +467,6 @@ elf_machine_plt_value (struct link_map *map, const ElfW(Rel) *reloc, return value; } -/* The semantics of zero/non-zero values of undefined symbols differs - depending on whether the non-PIC ABI is in use. Under the non-PIC - ABI, a non-zero value indicates that there is an address reference - to the symbol and thus it must always be resolved (except when - resolving a jump slot relocation) to the PLT entry whose address is - provided as the symbol's value; a zero value indicates that this - canonical-address behaviour is not required. Yet under the classic - MIPS psABI, a zero value indicates that there is an address - reference to the function and the dynamic linker must resolve the - symbol immediately upon loading. To avoid conflict, symbols for - which the dynamic linker must assume the non-PIC ABI semantics are - marked with the STO_MIPS_PLT flag. */ -#define ELF_MACHINE_SYM_NO_MATCH(sym) \ - ((sym)->st_shndx == SHN_UNDEF && !((sym)->st_other & STO_MIPS_PLT)) - #endif /* !dl_machine_h */ #ifdef RESOLVE_MAP diff --git a/sysdeps/mips/elf_machine_sym_no_match.h b/sysdeps/mips/elf_machine_sym_no_match.h new file mode 100644 index 0000000000..f2be74caaf --- /dev/null +++ b/sysdeps/mips/elf_machine_sym_no_match.h @@ -0,0 +1,43 @@ +/* MIPS-specific handling of undefined symbols. + Copyright (C) 2008-2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _ELF_MACHINE_SYM_NO_MATCH_H +#define _ELF_MACHINE_SYM_NO_MATCH_H + +#include +#include + +/* The semantics of zero/non-zero values of undefined symbols differs + depending on whether the non-PIC ABI is in use. Under the non-PIC + ABI, a non-zero value indicates that there is an address reference + to the symbol and thus it must always be resolved (except when + resolving a jump slot relocation) to the PLT entry whose address is + provided as the symbol's value; a zero value indicates that this + canonical-address behaviour is not required. Yet under the classic + MIPS psABI, a zero value indicates that there is an address + reference to the function and the dynamic linker must resolve the + symbol immediately upon loading. To avoid conflict, symbols for + which the dynamic linker must assume the non-PIC ABI semantics are + marked with the STO_MIPS_PLT flag. */ +static inline bool +elf_machine_sym_no_match (const ElfW(Sym) *sym) +{ + return sym->st_shndx == SHN_UNDEF && !(sym->st_other & STO_MIPS_PLT); +} + +#endif /* _ELF_MACHINE_SYM_NO_MATCH_H */ From patchwork Thu Mar 26 15:56:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: develop--- via Libc-alpha X-Patchwork-Id: 1262085 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=2620:52:3:1:0:246e:9693:128c; helo=sourceware.org; envelope-from=libc-alpha-bounces@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=sourceware.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=estCqwcy; dkim-atps=neutral Received: from sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 48p8kT2Y4Bz9sRY for ; Fri, 27 Mar 2020 02:57:04 +1100 (AEDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 71AF7385E009; Thu, 26 Mar 2020 15:57:00 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 71AF7385E009 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1585238220; bh=DBiueuge2woMuIOgRoUnAEHG6R0rtCC+ndEK3teLTnM=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=estCqwcy7Txqh9QomPXPBanD+d2bdhUz92cDTB8RRWSKU595Um83woH6rgD5GXHfp GlWqmxotlWzzU1NLOCGYuS6b6/Z1j7YfZJkjx0JG6EljZe9gfmSdp25dmRQn3ea9u0 SFnegaeq/svtxeyOm8AMzlUD3GKt8iIG38cVNwOE= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail.efficios.com (mail.efficios.com [167.114.26.124]) by sourceware.org (Postfix) with ESMTPS id 3D3C5385E00D for ; Thu, 26 Mar 2020 15:56:58 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 3D3C5385E00D Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id E54D72777DE; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id yCw0QbmJWdnN; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 8D8A4277BE3; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 8D8A4277BE3 X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id mYHUgwj2doVv; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) Received: from localhost.localdomain (192-222-181-218.qc.cable.ebox.net [192.222.181.218]) by mail.efficios.com (Postfix) with ESMTPSA id 307722777D8; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) To: Carlos O'Donell Subject: [PATCH glibc 2/9] Move elf/elf_machine_sym_no_match.h to sysdeps/generic Date: Thu, 26 Mar 2020 11:56:26 -0400 Message-Id: <20200326155633.18236-3-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> References: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> X-Spam-Status: No, score=-27.8 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, SPF_HELO_NONE, SPF_PASS, TVD_SPACE_RATIO, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mathieu Desnoyers via Libc-alpha From: develop--- via Libc-alpha Reply-To: Mathieu Desnoyers Cc: libc-alpha@sourceware.org, Joseph Myers , Mathieu Desnoyers Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" sysdeps/generic/elf_machine_sym_no_match.h matches sysdeps/mips/elf_machine_sym_no_match.h better. Suggested-by: H.J. Lu Signed-off-by: Mathieu Desnoyers CC: Florian Weimer --- {elf => sysdeps/generic}/elf_machine_sym_no_match.h | 0 1 file changed, 0 insertions(+), 0 deletions(-) rename {elf => sysdeps/generic}/elf_machine_sym_no_match.h (100%) diff --git a/elf/elf_machine_sym_no_match.h b/sysdeps/generic/elf_machine_sym_no_match.h similarity index 100% rename from elf/elf_machine_sym_no_match.h rename to sysdeps/generic/elf_machine_sym_no_match.h From patchwork Thu Mar 26 15:56:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: develop--- via Libc-alpha X-Patchwork-Id: 1262089 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=2620:52:3:1:0:246e:9693:128c; helo=sourceware.org; envelope-from=libc-alpha-bounces@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=sourceware.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=mof2QGca; dkim-atps=neutral Received: from sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 48p8kq5ngcz9sRY for ; Fri, 27 Mar 2020 02:57:23 +1100 (AEDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 1DF5D385E824; Thu, 26 Mar 2020 15:57:05 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 1DF5D385E824 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1585238225; bh=AshOy8aZJEYLc1zvn15TooVvUXkYLFOIZIYpxsNsy+o=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=mof2QGcaMTmCE7JkR+sKyatILLYKfYeGIoEpFHl9X3cIgNtEq9YOWzUOUSd9kwjj4 h4H9ch8Ts/W9D3Gp+a+scjt1GFnfRrs0Ort/sBjFuCKOXCYsJcWQHDeJggkZaRnPSz nI1R26UGDAFx6U1jwONQeZ7c/L1HEvJNRgq8TYW0= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail.efficios.com (mail.efficios.com [167.114.26.124]) by sourceware.org (Postfix) with ESMTPS id 8CA84385E00D for ; Thu, 26 Mar 2020 15:57:00 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 8CA84385E00D Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 4C6572772CD; Thu, 26 Mar 2020 11:57:00 -0400 (EDT) Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id uynFwq7kFoSU; Thu, 26 Mar 2020 11:56:59 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id A1B522777DA; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com A1B522777DA X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id 5IFtd4g7T5lu; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) Received: from localhost.localdomain (192-222-181-218.qc.cable.ebox.net [192.222.181.218]) by mail.efficios.com (Postfix) with ESMTPSA id 5FB68277D3B; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) To: Carlos O'Donell Subject: [PATCH glibc 3/9] Implement __libc_early_init Date: Thu, 26 Mar 2020 11:56:27 -0400 Message-Id: <20200326155633.18236-4-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> References: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> X-Spam-Status: No, score=-29.3 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, KAM_STOCKGEN, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mathieu Desnoyers via Libc-alpha From: develop--- via Libc-alpha Reply-To: Mathieu Desnoyers Cc: libc-alpha@sourceware.org, Joseph Myers Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" From: Florian Weimer This function is defined in libc.so, and the dynamic loader calls right after relocation has been finished, before any ELF constructors or the preinit function is invoked. It is also used in the static build for initializing parts of the static libc. To locate __libc_early_init, a direct symbol lookup function is used, _dl_lookup_direct. It does not search the entire symbol scope and consults merely a single link map. This function could also be used to implement lookups in the vDSO (as an optimization). A per-namespace variable (libc_map) is added for locating libc.so, to avoid repeated traversals of the search scope. It is similar to GL(dl_initfirst). An alternative would have been to thread a context argument from _dl_open down to _dl_map_object_from_fd (where libc.so is identified). This could have avoided the global variable, but the change would be larger as a result. It would not have been possible to use this to replace GL(dl_initfirst) because that global variable is used to pass the function pointer past the stack switch from dl_main to the main program. Replacing that requires adding a new argument to _dl_init, which in turn needs changes to the architecture-specific libc.so startup code written in assembler. __libc_early_init should not be used to replace _dl_var_init (as it exists today on some architectures). Instead, _dl_lookup_direct should be used to look up a new variable symbol in libc.so, and that should then be initialized from the dynamic loader, immediately after the object has been loaded in _dl_map_object_from_fd (before relocation is run). This way, more IFUNC resolvers which depend on these variables will work. This version was tested on x86_64-linux-gnu. Reviewed-by: Carlos O'Donell --- csu/init-first.c | 4 - csu/libc-start.c | 5 ++ elf/Makefile | 5 +- elf/Versions | 1 + elf/dl-call-libc-early-init.c | 41 ++++++++++ elf/dl-load.c | 9 +++ elf/dl-lookup-direct.c | 116 ++++++++++++++++++++++++++++ elf/dl-open.c | 24 ++++++ elf/libc-early-init.h | 35 +++++++++ elf/libc_early_init.c | 27 +++++++ elf/rtld.c | 4 + sysdeps/generic/ldsodefs.h | 17 ++++ sysdeps/mach/hurd/i386/init-first.c | 4 - 13 files changed, 282 insertions(+), 10 deletions(-) create mode 100644 elf/dl-call-libc-early-init.c create mode 100644 elf/dl-lookup-direct.c create mode 100644 elf/libc-early-init.h create mode 100644 elf/libc_early_init.c diff --git a/csu/init-first.c b/csu/init-first.c index 264e6f348d..d214af7116 100644 --- a/csu/init-first.c +++ b/csu/init-first.c @@ -16,7 +16,6 @@ License along with the GNU C Library; if not, see . */ -#include #include #include #include @@ -75,9 +74,6 @@ _init_first (int argc, char **argv, char **envp) __init_misc (argc, argv, envp); - /* Initialize ctype data. */ - __ctype_init (); - #if defined SHARED && !defined NO_CTORS_DTORS_SECTIONS __libc_global_ctors (); #endif diff --git a/csu/libc-start.c b/csu/libc-start.c index 12468c5a89..ccc743c9d1 100644 --- a/csu/libc-start.c +++ b/csu/libc-start.c @@ -22,6 +22,7 @@ #include #include #include +#include #include @@ -238,6 +239,10 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL), __cxa_atexit ((void (*) (void *)) rtld_fini, NULL, NULL); #ifndef SHARED + /* Perform early initialization. In the shared case, this function + is called from the dynamic loader as early as possible. */ + __libc_early_init (); + /* Call the initializer of the libc. This is only needed here if we are compiling for the static library in which case we haven't run the constructors in `_dl_start_user'. */ diff --git a/elf/Makefile b/elf/Makefile index da689a2c7b..23b6043cdb 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -25,7 +25,7 @@ headers = elf.h bits/elfclass.h link.h bits/link.h routines = $(all-dl-routines) dl-support dl-iteratephdr \ dl-addr dl-addr-obj enbl-secure dl-profstub \ dl-origin dl-libc dl-sym dl-sysdep dl-error \ - dl-reloc-static-pie + dl-reloc-static-pie libc_early_init # The core dynamic linking functions are in libc for the static and # profiled libraries. @@ -33,7 +33,8 @@ dl-routines = $(addprefix dl-,load lookup object reloc deps hwcaps \ runtime init fini debug misc \ version profile tls origin scope \ execstack open close trampoline \ - exception sort-maps) + exception sort-maps lookup-direct \ + call-libc-early-init) ifeq (yes,$(use-ldconfig)) dl-routines += dl-cache endif diff --git a/elf/Versions b/elf/Versions index 705489fc51..3be879c4ad 100644 --- a/elf/Versions +++ b/elf/Versions @@ -26,6 +26,7 @@ libc { _dl_open_hook; _dl_open_hook2; _dl_sym; _dl_vsym; __libc_dlclose; __libc_dlopen_mode; __libc_dlsym; __libc_dlvsym; + __libc_early_init; # Internal error handling support. Interposes the functions in ld.so. _dl_signal_exception; _dl_catch_exception; diff --git a/elf/dl-call-libc-early-init.c b/elf/dl-call-libc-early-init.c new file mode 100644 index 0000000000..6c3ac5bfe7 --- /dev/null +++ b/elf/dl-call-libc-early-init.c @@ -0,0 +1,41 @@ +/* Invoke the early initialization function in libc.so. + Copyright (C) 2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include +#include + +void +_dl_call_libc_early_init (struct link_map *libc_map) +{ + /* There is nothing to do if we did not actually load libc.so. */ + if (libc_map == NULL) + return; + + const ElfW(Sym) *sym + = _dl_lookup_direct (libc_map, "__libc_early_init", + 0x69682ac, /* dl_new_hash output. */ + "GLIBC_PRIVATE", + 0x0963cf85); /* _dl_elf_hash output. */ + assert (sym != NULL); + __typeof (__libc_early_init) *early_init + = DL_SYMBOL_ADDRESS (libc_map, sym); + early_init (); +} diff --git a/elf/dl-load.c b/elf/dl-load.c index a6b80f9395..06f2ba7264 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -30,6 +30,7 @@ #include #include #include +#include /* Type for the buffer we put the ELF header and hopefully the program header. This buffer does not really have to be too large. In most @@ -1374,6 +1375,14 @@ cannot enable executable stack as shared object requires"); add_name_to_object (l, ((const char *) D_PTR (l, l_info[DT_STRTAB]) + l->l_info[DT_SONAME]->d_un.d_val)); + /* If we have newly loaded libc.so, update the namespace + description. */ + if (GL(dl_ns)[nsid].libc_map == NULL + && l->l_info[DT_SONAME] != NULL + && strcmp (((const char *) D_PTR (l, l_info[DT_STRTAB]) + + l->l_info[DT_SONAME]->d_un.d_val), LIBC_SO) == 0) + GL(dl_ns)[nsid].libc_map = l; + /* _dl_close can only eventually undo the module ID assignment (via remove_slotinfo) if this function returns a pointer to a link map. Therefore, delay this step until all possibilities for diff --git a/elf/dl-lookup-direct.c b/elf/dl-lookup-direct.c new file mode 100644 index 0000000000..190b826e1e --- /dev/null +++ b/elf/dl-lookup-direct.c @@ -0,0 +1,116 @@ +/* Look up a symbol in a single specified object. + Copyright (C) 1995-2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include + +/* This function corresponds to do_lookup_x in elf/dl-lookup.c. The + variant here is simplified because it requires symbol + versioning. */ +static const ElfW(Sym) * +check_match (const struct link_map *const map, const char *const undef_name, + const char *version, uint32_t version_hash, + const Elf_Symndx symidx) +{ + const ElfW(Sym) *symtab = (const void *) D_PTR (map, l_info[DT_SYMTAB]); + const ElfW(Sym) *sym = &symtab[symidx]; + + unsigned int stt = ELFW(ST_TYPE) (sym->st_info); + if (__glibc_unlikely ((sym->st_value == 0 /* No value. */ + && sym->st_shndx != SHN_ABS + && stt != STT_TLS) + || elf_machine_sym_no_match (sym))) + return NULL; + + /* Ignore all but STT_NOTYPE, STT_OBJECT, STT_FUNC, + STT_COMMON, STT_TLS, and STT_GNU_IFUNC since these are no + code/data definitions. */ +#define ALLOWED_STT \ + ((1 << STT_NOTYPE) | (1 << STT_OBJECT) | (1 << STT_FUNC) \ + | (1 << STT_COMMON) | (1 << STT_TLS) | (1 << STT_GNU_IFUNC)) + if (__glibc_unlikely (((1 << stt) & ALLOWED_STT) == 0)) + return NULL; + + const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]); + + if (strcmp (strtab + sym->st_name, undef_name) != 0) + /* Not the symbol we are looking for. */ + return NULL; + + ElfW(Half) ndx = map->l_versyms[symidx] & 0x7fff; + if (map->l_versions[ndx].hash != version_hash + || strcmp (map->l_versions[ndx].name, version) != 0) + /* It's not the version we want. */ + return NULL; + + return sym; +} + + +/* This function corresponds to do_lookup_x in elf/dl-lookup.c. The + variant here is simplified because it does not search object + dependencies. It is optimized for a successful lookup. */ +const ElfW(Sym) * +_dl_lookup_direct (struct link_map *map, + const char *undef_name, uint32_t new_hash, + const char *version, uint32_t version_hash) +{ + const ElfW(Addr) *bitmask = map->l_gnu_bitmask; + if (__glibc_likely (bitmask != NULL)) + { + Elf32_Word bucket = map->l_gnu_buckets[new_hash % map->l_nbuckets]; + if (bucket != 0) + { + const Elf32_Word *hasharr = &map->l_gnu_chain_zero[bucket]; + + do + if (((*hasharr ^ new_hash) >> 1) == 0) + { + Elf_Symndx symidx = ELF_MACHINE_HASH_SYMIDX (map, hasharr); + const ElfW(Sym) *sym = check_match (map, undef_name, + version, version_hash, + symidx); + if (sym != NULL) + return sym; + } + while ((*hasharr++ & 1u) == 0); + } + } + else + { + /* Fallback code for lack of GNU_HASH support. */ + uint32_t old_hash = _dl_elf_hash (undef_name); + + /* Use the old SysV-style hash table. Search the appropriate + hash bucket in this object's symbol table for a definition + for the same symbol name. */ + for (Elf_Symndx symidx = map->l_buckets[old_hash % map->l_nbuckets]; + symidx != STN_UNDEF; + symidx = map->l_chain[symidx]) + { + const ElfW(Sym) *sym = check_match (map, undef_name, + version, version_hash, symidx); + if (sym != NULL) + return sym; + } + } + + return NULL; +} diff --git a/elf/dl-open.c b/elf/dl-open.c index 7b3b177aa6..6ff6b64b46 100644 --- a/elf/dl-open.c +++ b/elf/dl-open.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #include @@ -57,6 +58,13 @@ struct dl_open_args (non-negative). */ unsigned int original_global_scope_pending_adds; + /* Set to true if libc.so was already loaded into the namespace at + the time dl_open_worker was called. This is used to determine + whether libc.so early initialization needs to before, and whether + to roll back the cached libc_map value in the namespace in case + of a dlopen failure. */ + bool libc_already_loaded; + /* Original parameters to the program and the current environment. */ int argc; char **argv; @@ -500,6 +508,11 @@ dl_open_worker (void *a) args->nsid = call_map->l_ns; } + /* The namespace ID is now known. Keep track of whether libc.so was + already loaded, to determine whether it is necessary to call the + early initialization routine (or clear libc_map on error). */ + args->libc_already_loaded = GL(dl_ns)[args->nsid].libc_map != NULL; + /* Retain the old value, so that it can be restored. */ args->original_global_scope_pending_adds = GL (dl_ns)[args->nsid]._ns_global_scope_pending_adds; @@ -734,6 +747,11 @@ dl_open_worker (void *a) if (relocation_in_progress) LIBC_PROBE (reloc_complete, 3, args->nsid, r, new); + /* If libc.so was not there before, attempt to call its early + initialization routine. */ + if (!args->libc_already_loaded) + _dl_call_libc_early_init (GL(dl_ns)[args->nsid].libc_map); + #ifndef SHARED DL_STATIC_INIT (new); #endif @@ -828,6 +846,7 @@ no more namespaces available for dlmopen()")); args.caller_dlopen = caller_dlopen; args.map = NULL; args.nsid = nsid; + args.libc_already_loaded = true; /* No reset below with early failure. */ args.argc = argc; args.argv = argv; args.env = env; @@ -856,6 +875,11 @@ no more namespaces available for dlmopen()")); /* See if an error occurred during loading. */ if (__glibc_unlikely (exception.errstring != NULL)) { + /* Avoid keeping around a dangling reference to the libc.so link + map in case it has been cached in libc_map. */ + if (!args.libc_already_loaded) + GL(dl_ns)[nsid].libc_map = NULL; + /* Remove the object from memory. It may be in an inconsistent state if relocation failed, for example. */ if (args.map) diff --git a/elf/libc-early-init.h b/elf/libc-early-init.h new file mode 100644 index 0000000000..02b855754e --- /dev/null +++ b/elf/libc-early-init.h @@ -0,0 +1,35 @@ +/* Early initialization of libc.so. + Copyright (C) 2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _LIBC_EARLY_INIT_H +#define _LIBC_EARLY_INIT_H + +struct link_map; + +/* If LIBC_MAP is not NULL, look up the __libc_early_init symbol in it + and call this function. */ +void _dl_call_libc_early_init (struct link_map *libc_map) attribute_hidden; + +/* In the shared case, this function is defined in libc.so and invoked + from ld.so (or on the fist static dlopen) after complete relocation + of a new loaded libc.so, but before user-defined ELF constructors + run. In the static case, this function is called directly from the + startup code. */ +void __libc_early_init (void); + +#endif /* _LIBC_EARLY_INIT_H */ diff --git a/elf/libc_early_init.c b/elf/libc_early_init.c new file mode 100644 index 0000000000..1ac66d895d --- /dev/null +++ b/elf/libc_early_init.c @@ -0,0 +1,27 @@ +/* Early initialization of libc.so, libc.so side. + Copyright (C) 2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include + +void +__libc_early_init (void) +{ + /* Initialize ctype data. */ + __ctype_init (); +} diff --git a/elf/rtld.c b/elf/rtld.c index 51dfaf966a..912dddd5cd 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -45,6 +45,7 @@ #include #include #include +#include #include @@ -2332,6 +2333,9 @@ ERROR: '%s': cannot process note segment.\n", _dl_argv[0]); rtld_timer_accum (&relocate_time, start); } + /* Relocation is complete. Perform early libc initialization. */ + _dl_call_libc_early_init (GL(dl_ns)[LM_ID_BASE].libc_map); + /* Do any necessary cleanups for the startup OS interface code. We do these now so that no calls are made after rtld re-relocation which might be resolved to different functions than we expect. diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index 497938ffa2..5ff4a2831b 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -336,6 +336,10 @@ struct rtld_global recursive dlopen calls from ELF constructors. */ unsigned int _ns_global_scope_pending_adds; + /* Once libc.so has been loaded into the namespace, this points to + its link map. */ + struct link_map *libc_map; + /* Search table for unique objects. */ struct unique_sym_table { @@ -946,6 +950,19 @@ extern lookup_t _dl_lookup_symbol_x (const char *undef, attribute_hidden; +/* Restricted version of _dl_lookup_symbol_x. Searches MAP (and only + MAP) for the symbol UNDEF_NAME, with GNU hash NEW_HASH (computed + with dl_new_hash), symbol version VERSION, and symbol version hash + VERSION_HASH (computed with _dl_elf_hash). Returns a pointer to + the symbol table entry in MAP on success, or NULL on failure. MAP + must have symbol versioning information, or otherwise the result is + undefined. */ +const ElfW(Sym) *_dl_lookup_direct (struct link_map *map, + const char *undef_name, + uint32_t new_hash, + const char *version, + uint32_t version_hash) attribute_hidden; + /* Add the new link_map NEW to the end of the namespace list. */ extern void _dl_add_to_namespace_list (struct link_map *new, Lmid_t nsid) attribute_hidden; diff --git a/sysdeps/mach/hurd/i386/init-first.c b/sysdeps/mach/hurd/i386/init-first.c index 92bf45223f..a7dd4895d9 100644 --- a/sysdeps/mach/hurd/i386/init-first.c +++ b/sysdeps/mach/hurd/i386/init-first.c @@ -17,7 +17,6 @@ . */ #include -#include #include #include #include @@ -85,9 +84,6 @@ posixland_init (int argc, char **argv, char **envp) #endif __init_misc (argc, argv, envp); - /* Initialize ctype data. */ - __ctype_init (); - #if defined SHARED && !defined NO_CTORS_DTORS_SECTIONS __libc_global_ctors (); #endif From patchwork Thu Mar 26 15:56:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: develop--- via Libc-alpha X-Patchwork-Id: 1262088 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=2620:52:3:1:0:246e:9693:128c; helo=sourceware.org; envelope-from=libc-alpha-bounces@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=sourceware.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=iJzTpH0K; dkim-atps=neutral Received: from sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 48p8kl3ZLXz9sRY for ; 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Thu, 26 Mar 2020 11:56:58 -0400 (EDT) Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id 2mCQYhzW0Fjt; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id C30072777DD; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com C30072777DD X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id O9G2gGurESXw; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) Received: from localhost.localdomain (192-222-181-218.qc.cable.ebox.net [192.222.181.218]) by mail.efficios.com (Postfix) with ESMTPSA id 82894276E4E; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) To: Carlos O'Donell Subject: [PATCH glibc 4/9] nptl: Start new threads with all signals blocked [BZ #25098] Date: Thu, 26 Mar 2020 11:56:28 -0400 Message-Id: <20200326155633.18236-5-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> References: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> X-Spam-Status: No, score=-30.0 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mathieu Desnoyers via Libc-alpha From: develop--- via Libc-alpha Reply-To: Mathieu Desnoyers Cc: libc-alpha@sourceware.org, Joseph Myers Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" From: Florian Weimer New threads inherit the signal mask from the current thread. This means that signal handlers can run on the newly created thread immediately after the kernel has created the userspace thread, even before glibc has initialized the TCB. Consequently, new threads can observe uninitialized ctype data, among other things. To address this, block all signals before starting the thread, and pass the original signal mask to the start routine wrapper. On the new thread, first perform all thread initialization, and then unblock signals. The cost of doing this is two rt_sigprocmask system calls on the old thread, and one rt_sigprocmask system call on the new thread. (If there was a way to clone a new thread with a signals disabled, this could be brought down to one system call each.) The thread descriptor increases in size, too, and sigset_t is fairly large. This increase could be brought down by reusing space the in the descriptor which is not needed before running user code, or by switching to an internal sigset_t definition which only covers the signals supported by the kernel definition. (Part of the thread descriptor size increase is already offset by reduced stack usage in the thread start wrapper routine after this commit.) Reviewed-by: Carlos O'Donell --- nptl/descr.h | 10 +++++++--- nptl/pthread_create.c | 46 +++++++++++++++++++++++-------------------- 2 files changed, 32 insertions(+), 24 deletions(-) diff --git a/nptl/descr.h b/nptl/descr.h index 9dcf480bdf..e1c7db5473 100644 --- a/nptl/descr.h +++ b/nptl/descr.h @@ -332,9 +332,8 @@ struct pthread /* True if thread must stop at startup time. */ bool stopped_start; - /* The parent's cancel handling at the time of the pthread_create - call. This might be needed to undo the effects of a cancellation. */ - int parent_cancelhandling; + /* Formerly used for dealing with cancellation. */ + int parent_cancelhandling_unsed; /* Lock to synchronize access to the descriptor. */ int lock; @@ -391,6 +390,11 @@ struct pthread /* Resolver state. */ struct __res_state res; + /* Signal mask for the new thread. Used during thread startup to + restore the signal mask. (Threads are launched with all signals + masked.) */ + sigset_t sigmask; + /* Indicates whether is a C11 thread created by thrd_creat. */ bool c11; diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c index 7c752d0f99..afd379e89a 100644 --- a/nptl/pthread_create.c +++ b/nptl/pthread_create.c @@ -369,7 +369,6 @@ __free_tcb (struct pthread *pd) } } - /* Local function to start thread and handle cleanup. createthread.c defines the macro START_THREAD_DEFN to the declaration that its create_thread function will refer to, and @@ -385,10 +384,6 @@ START_THREAD_DEFN /* Initialize pointers to locale data. */ __ctype_init (); - /* Allow setxid from now onwards. */ - if (__glibc_unlikely (atomic_exchange_acq (&pd->setxid_futex, 0) == -2)) - futex_wake (&pd->setxid_futex, 1, FUTEX_PRIVATE); - #ifndef __ASSUME_SET_ROBUST_LIST if (__set_robust_list_avail >= 0) #endif @@ -399,18 +394,6 @@ START_THREAD_DEFN sizeof (struct robust_list_head)); } - /* If the parent was running cancellation handlers while creating - the thread the new thread inherited the signal mask. Reset the - cancellation signal mask. */ - if (__glibc_unlikely (pd->parent_cancelhandling & CANCELING_BITMASK)) - { - sigset_t mask; - __sigemptyset (&mask); - __sigaddset (&mask, SIGCANCEL); - INTERNAL_SYSCALL_CALL (rt_sigprocmask, SIG_UNBLOCK, &mask, - NULL, _NSIG / 8); - } - /* This is where the try/finally block should be created. For compilers without that support we do use setjmp. */ struct pthread_unwind_buf unwind_buf; @@ -432,6 +415,12 @@ START_THREAD_DEFN unwind_buf.priv.data.prev = NULL; unwind_buf.priv.data.cleanup = NULL; + __libc_signal_restore_set (&pd->sigmask); + + /* Allow setxid from now onwards. */ + if (__glibc_unlikely (atomic_exchange_acq (&pd->setxid_futex, 0) == -2)) + futex_wake (&pd->setxid_futex, 1, FUTEX_PRIVATE); + if (__glibc_likely (! not_first_call)) { /* Store the new cleanup handler info. */ @@ -722,10 +711,6 @@ __pthread_create_2_1 (pthread_t *newthread, const pthread_attr_t *attr, CHECK_THREAD_SYSINFO (pd); #endif - /* Inform start_thread (above) about cancellation state that might - translate into inherited signal state. */ - pd->parent_cancelhandling = THREAD_GETMEM (THREAD_SELF, cancelhandling); - /* Determine scheduling parameters for the thread. */ if (__builtin_expect ((iattr->flags & ATTR_FLAG_NOTINHERITSCHED) != 0, 0) && (iattr->flags & (ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET)) != 0) @@ -771,6 +756,21 @@ __pthread_create_2_1 (pthread_t *newthread, const pthread_attr_t *attr, ownership of PD (see CONCURRENCY NOTES above). */ bool stopped_start = false; bool thread_ran = false; + /* Block all signals, so that the new thread starts out with + signals disabled. This avoids race conditions in the thread + startup. */ + sigset_t original_sigmask; + __libc_signal_block_all (&original_sigmask); + + /* Conceptually, the new thread needs to inherit the signal mask of + this thread. Therefore, it needs to restore the saved signal + mask of this thread, so save it in the startup information. */ + pd->sigmask = original_sigmask; + + /* Reset the cancellation signal mask in case this thread is running + cancellation. */ + __sigdelset (&pd->sigmask, SIGCANCEL); + /* Start the thread. */ if (__glibc_unlikely (report_thread_creation (pd))) { @@ -813,6 +813,10 @@ __pthread_create_2_1 (pthread_t *newthread, const pthread_attr_t *attr, retval = create_thread (pd, iattr, &stopped_start, STACK_VARIABLES_ARGS, &thread_ran); + /* Return to the previous signal mask, after creating the new + thread. */ + __libc_signal_restore_set (&original_sigmask); + if (__glibc_unlikely (retval != 0)) { if (thread_ran) From patchwork Thu Mar 26 15:56:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: develop--- via Libc-alpha X-Patchwork-Id: 1262097 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; 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Thu, 26 Mar 2020 11:57:02 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 54553277EB6; Thu, 26 Mar 2020 11:57:00 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 54553277EB6 X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id kuaCJhV4wWNj; Thu, 26 Mar 2020 11:57:00 -0400 (EDT) Received: from localhost.localdomain (192-222-181-218.qc.cable.ebox.net [192.222.181.218]) by mail.efficios.com (Postfix) with ESMTPSA id A2C2C277F07; Thu, 26 Mar 2020 11:56:57 -0400 (EDT) To: Carlos O'Donell Subject: [PATCH glibc 5/9] glibc: Perform rseq(2) registration at C startup and thread creation (v17) Date: Thu, 26 Mar 2020 11:56:29 -0400 Message-Id: <20200326155633.18236-6-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> References: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> X-Spam-Status: No, score=-30.2 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mathieu Desnoyers via Libc-alpha From: develop--- via Libc-alpha Reply-To: Mathieu Desnoyers Cc: Rich Felker , libc-alpha@sourceware.org, linux-api@vger.kernel.org, Boqun Feng , Will Deacon , linux-kernel@vger.kernel.org, Peter Zijlstra , Ben Maurer , Mathieu Desnoyers , Dave Watson , Thomas Gleixner , "Paul E. McKenney" , Paul Turner , Joseph Myers Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" Register rseq(2) TLS for each thread (including main), and unregister for each thread (excluding main). "rseq" stands for Restartable Sequences. See the rseq(2) man page proposed here: https://lkml.org/lkml/2018/9/19/647 This patch depends on three patches from Florian Weimer: - Introduce - Implement __libc_early_init - nptl: Start new threads with all signals blocked [BZ #25098] those are based on glibc master branch commit 1fabdb99084df004f7f4cdc7068d1be209a258be. The rseq(2) system call was merged into Linux 4.18. Signed-off-by: Mathieu Desnoyers CC: Carlos O'Donell CC: Florian Weimer CC: Joseph Myers CC: Szabolcs Nagy CC: Thomas Gleixner CC: Ben Maurer CC: Peter Zijlstra CC: "Paul E. McKenney" CC: Boqun Feng CC: Will Deacon CC: Dave Watson CC: Paul Turner CC: Rich Felker CC: libc-alpha@sourceware.org CC: linux-kernel@vger.kernel.org CC: linux-api@vger.kernel.org --- Changes since v1: - Move __rseq_refcount to an extra field at the end of __rseq_abi to eliminate one symbol. All libraries/programs which try to register rseq (glibc, early-adopter applications, early-adopter libraries) should use the rseq refcount. It becomes part of the ABI within a user-space process, but it's not part of the ABI shared with the kernel per se. - Restructure how this code is organized so glibc keeps building on non-Linux targets. - Use non-weak symbol for __rseq_abi. - Move rseq registration/unregistration implementation into its own nptl/rseq.c compile unit. - Move __rseq_abi symbol under GLIBC_2.29. Changes since v2: - Move __rseq_refcount to its own symbol, which is less ugly than trying to play tricks with the rseq uapi. - Move __rseq_abi from nptl to csu (C start up), so it can be used across glibc, including memory allocator and sched_getcpu(). The __rseq_refcount symbol is kept in nptl, because there is no reason to use it elsewhere in glibc. Changes since v3: - Set __rseq_refcount TLS to 1 on register/set to 0 on unregister because glibc is the first/last user. - Unconditionally register/unregister rseq at thread start/exit, because glibc is the first/last user. - Add missing abilist items. - Rebase on glibc master commit a502c5294. - Add NEWS entry. Changes since v4: - Do not use "weak" symbols for __rseq_abi and __rseq_refcount. Based on "System V Application Binary Interface", weak only affects the link editor, not the dynamic linker. - Install a new sys/rseq.h system header on Linux, which contains the RSEQ_SIG definition, __rseq_abi declaration and __rseq_refcount declaration. Move those definition/declarations from rseq-internal.h to the installed sys/rseq.h header. - Considering that rseq is only available on Linux, move csu/rseq.c to sysdeps/unix/sysv/linux/rseq-sym.c. - Move __rseq_refcount from nptl/rseq.c to sysdeps/unix/sysv/linux/rseq-sym.c, so it is only defined on Linux. - Move both ABI definitions for __rseq_abi and __rseq_refcount to sysdeps/unix/sysv/linux/Versions, so they only appear on Linux. - Document __rseq_abi and __rseq_refcount volatile. - Document the RSEQ_SIG signature define. - Move registration functions from rseq.c to rseq-internal.h static inline functions. Introduce empty stubs in misc/rseq-internal.h, which can be overridden by architecture code in sysdeps/unix/sysv/linux/rseq-internal.h. - Rename __rseq_register_current_thread and __rseq_unregister_current_thread to rseq_register_current_thread and rseq_unregister_current_thread, now that those are only visible as internal static inline functions. - Invoke rseq_register_current_thread() from libc-start.c LIBC_START_MAIN rather than nptl init, so applications not linked against libpthread.so have rseq registered for their main() thread. Note that it is invoked separately for SHARED and !SHARED builds. Changes since v5: - Replace __rseq_refcount by __rseq_lib_abi, which contains two uint32_t: register_state and refcount. The "register_state" field allows inhibiting rseq registration from signal handlers nested on top of glibc registration and occuring after rseq unregistration by glibc. - Introduce enum rseq_register_state, which contains the states allowed for the struct rseq_lib_abi register_state field. Changes since v6: - Introduce bits/rseq.h to define RSEQ_SIG for each architecture. The generic bits/rseq.h does not define RSEQ_SIG, meaning that each architecture implementing rseq needs to implement bits/rseq.h. - Rename enum item RSEQ_REGISTER_NESTED to RSEQ_REGISTER_ONGOING. - Port to glibc-2.29. Changes since v7: - Remove __rseq_lib_abi symbol, including refcount and register_state fields. - Remove reference counting and nested signals handling from registration/unregistration functions. - Introduce new __rseq_handled exported symbol, which is set to 1 by glibc on C startup when it handles restartable sequences. This allows glibc to coexist with early adopter libraries and applications wishing to register restartable sequences when it is not handled by glibc. - Introduce rseq_init (), which sets __rseq_handled to 1 from C startup. - Update NEWS entry. - Update comments at the beginning of new files. - Registration depends on both __NR_rseq and RSEQ_SIG. - Remove ARM, powerpc, MIPS RSEQ_SIG until we agree with maintainers on the signature choice. - Update x86, s390 RSEQ_SIG based on discussion with arch maintainers. - Remove rseq-internal.h from headers list of misc/Makefile, so it it not installed by make install. Changes since v8: - Introduce RSEQ_SIG_CODE and RSEQ_SIG_DATA on aarch64 to handle compiling with -mbig-endian. Changes since v9: - Update Changelog. - Remove unneeded new file comment header newlines. Changes since v10: - Remove volatile from __rseq_abi declaration. - Document that __rseq_handled is about library managing rseq registration, independently of whether rseq is available or not. - Move __rseq_handled symbol to ld.so, initialize this symbol within the dynamic linker initialization for both shared (rtld.c) and static (dl-support.c) builds. - Only register the rseq TLS on initialization once in multiple-libc scenarios. Use rtld_active () for this purpose. - In the static libc case, register the rseq TLS after LD_PRELOAD constructors are run, so it matches the order of this initialization vs LD_PRELOAD contructors execution for the shared libc. - Agreed on signature choice with powerpc and MIPS maintainers, re-adding those signatures, - The main architecture still left out signature-wise is ARM32. Changes since v11: - Rebase on glibc 2.30. - Re-introduce ARM RSEQ_SIG following feedback from Will Deacon. Changes since v12: - Remove __rseq_handled, - Rely on OS implicit rseq unregistration on thread teardown, - Register main thread in __libc_early_init (). - Add Restartable Sequences entry to threads manual. Changes since v13: - Update following be/le abilist split for arm, microblaze, and sh. - Update manual to add the __rseq_abi variable and RSEQ_SIG macro to generate manual index entries, and add missing "Restartable Sequences" menu entry to the threads chapter. Changes since v14: - Update copyright range to include 2020. - Introduce __ASSUME_RSEQ defined for --enable-kernel=4.18.0 and higher. - Use ifdef __ASSUME_RSEQ rather than ifdef __NR_rseq to discover rseq availability. This is necessary now that the system call numbers are integrated within glibc. Changes since v15: - Remove __ASSUME_RSEQ from kernel features. - rseq internal: remove assume rseq - remove assume rseq and struct rseq def from sysdeps/unix/sysv/linux/rseq-sym.c - sys/rseq.h: detect rseq header, implement fallback - sysdeps/unix/sysv/linux/sys/rseq.h include cdefs.h, add _Static_assert to validate struct rseq and struct rseq_cs alignment. - sys/rseq.h: document that posix_memalign should be used rather than malloc if allocating struct rseq or struct rseq_cs on the heap. This is required to guarantee 32-byte alignement. Changes since v16: - Move rseq NEWS entry under 2.32. - Move new __rseq_abi symbol to GLIBC_2.32. Signed-off-by: Mathieu Desnoyers CC: Carlos O'Donell CC: Florian Weimer CC: Joseph Myers CC: Szabolcs Nagy CC: Thomas Gleixner CC: Ben Maurer CC: Peter Zijlstra CC: "Paul E. McKenney" CC: Boqun Feng CC: Will Deacon CC: Paul Turner CC: Rich Felker CC: libc-alpha@sourceware.org CC: linux-kernel@vger.kernel.org CC: linux-api@vger.kernel.org --- NEWS | 12 +- elf/libc_early_init.c | 3 + manual/threads.texi | 30 ++- misc/rseq-internal.h | 33 ++++ nptl/pthread_create.c | 12 ++ sysdeps/unix/sysv/linux/Makefile | 5 +- sysdeps/unix/sysv/linux/Versions | 3 + sysdeps/unix/sysv/linux/aarch64/bits/rseq.h | 43 ++++ sysdeps/unix/sysv/linux/aarch64/libc.abilist | 1 + sysdeps/unix/sysv/linux/alpha/libc.abilist | 1 + sysdeps/unix/sysv/linux/arm/be/libc.abilist | 1 + sysdeps/unix/sysv/linux/arm/bits/rseq.h | 83 ++++++++ sysdeps/unix/sysv/linux/arm/le/libc.abilist | 1 + sysdeps/unix/sysv/linux/bits/rseq.h | 29 +++ sysdeps/unix/sysv/linux/csky/libc.abilist | 1 + sysdeps/unix/sysv/linux/hppa/libc.abilist | 1 + sysdeps/unix/sysv/linux/i386/libc.abilist | 1 + sysdeps/unix/sysv/linux/ia64/libc.abilist | 1 + .../sysv/linux/m68k/coldfire/libc.abilist | 1 + .../unix/sysv/linux/m68k/m680x0/libc.abilist | 1 + .../sysv/linux/microblaze/be/libc.abilist | 1 + .../sysv/linux/microblaze/le/libc.abilist | 1 + sysdeps/unix/sysv/linux/mips/bits/rseq.h | 62 ++++++ .../sysv/linux/mips/mips32/fpu/libc.abilist | 1 + .../sysv/linux/mips/mips32/nofpu/libc.abilist | 1 + .../sysv/linux/mips/mips64/n32/libc.abilist | 1 + .../sysv/linux/mips/mips64/n64/libc.abilist | 1 + sysdeps/unix/sysv/linux/nios2/libc.abilist | 1 + sysdeps/unix/sysv/linux/powerpc/bits/rseq.h | 37 ++++ .../linux/powerpc/powerpc32/fpu/libc.abilist | 1 + .../powerpc/powerpc32/nofpu/libc.abilist | 1 + .../linux/powerpc/powerpc64/be/libc.abilist | 1 + .../linux/powerpc/powerpc64/le/libc.abilist | 1 + .../unix/sysv/linux/riscv/rv64/libc.abilist | 1 + sysdeps/unix/sysv/linux/rseq-internal.h | 73 +++++++ sysdeps/unix/sysv/linux/rseq-sym.c | 25 +++ sysdeps/unix/sysv/linux/s390/bits/rseq.h | 37 ++++ .../unix/sysv/linux/s390/s390-32/libc.abilist | 1 + .../unix/sysv/linux/s390/s390-64/libc.abilist | 1 + sysdeps/unix/sysv/linux/sh/be/libc.abilist | 1 + sysdeps/unix/sysv/linux/sh/le/libc.abilist | 1 + .../sysv/linux/sparc/sparc32/libc.abilist | 1 + .../sysv/linux/sparc/sparc64/libc.abilist | 1 + sysdeps/unix/sysv/linux/sys/rseq.h | 186 ++++++++++++++++++ sysdeps/unix/sysv/linux/x86/bits/rseq.h | 30 +++ .../unix/sysv/linux/x86_64/64/libc.abilist | 1 + .../unix/sysv/linux/x86_64/x32/libc.abilist | 1 + 47 files changed, 728 insertions(+), 5 deletions(-) create mode 100644 misc/rseq-internal.h create mode 100644 sysdeps/unix/sysv/linux/aarch64/bits/rseq.h create mode 100644 sysdeps/unix/sysv/linux/arm/bits/rseq.h create mode 100644 sysdeps/unix/sysv/linux/bits/rseq.h create mode 100644 sysdeps/unix/sysv/linux/mips/bits/rseq.h create mode 100644 sysdeps/unix/sysv/linux/powerpc/bits/rseq.h create mode 100644 sysdeps/unix/sysv/linux/rseq-internal.h create mode 100644 sysdeps/unix/sysv/linux/rseq-sym.c create mode 100644 sysdeps/unix/sysv/linux/s390/bits/rseq.h create mode 100644 sysdeps/unix/sysv/linux/sys/rseq.h create mode 100644 sysdeps/unix/sysv/linux/x86/bits/rseq.h diff --git a/NEWS b/NEWS index e0379fc53c..cf3e05d5f9 100644 --- a/NEWS +++ b/NEWS @@ -9,7 +9,17 @@ Version 2.32 Major new features: - * New locale added: ckb_IQ (Kurdish/Sorani spoken in Iraq) +* New locale added: ckb_IQ (Kurdish/Sorani spoken in Iraq) + +* Support for automatically registering threads with the Linux rseq(2) + system call has been added. This system call is implemented starting + from Linux 4.18. The Restartable Sequences ABI accelerates user-space + operations on per-cpu data. It allows user-space to perform updates + on per-cpu data without requiring heavy-weight atomic operations. + Automatically registering threads allows all libraries, including libc, + to make immediate use of the rseq(2) support by using the documented ABI. + See 'man 2 rseq' for the details of the ABI shared between libc and the + kernel. Deprecated and removed features, and other changes affecting compatibility: diff --git a/elf/libc_early_init.c b/elf/libc_early_init.c index 1ac66d895d..30466afea0 100644 --- a/elf/libc_early_init.c +++ b/elf/libc_early_init.c @@ -18,10 +18,13 @@ #include #include +#include void __libc_early_init (void) { /* Initialize ctype data. */ __ctype_init (); + /* Register rseq ABI to the kernel. */ + (void) rseq_register_current_thread (); } diff --git a/manual/threads.texi b/manual/threads.texi index 0858ef8f92..59f634e432 100644 --- a/manual/threads.texi +++ b/manual/threads.texi @@ -9,8 +9,10 @@ This chapter describes functions used for managing threads. POSIX threads. @menu -* ISO C Threads:: Threads based on the ISO C specification. -* POSIX Threads:: Threads based on the POSIX specification. +* ISO C Threads:: Threads based on the ISO C specification. +* POSIX Threads:: Threads based on the POSIX specification. +* Restartable Sequences:: Linux-specific Restartable Sequences + integration. @end menu @@ -881,3 +883,27 @@ Behaves like @code{pthread_timedjoin_np} except that the absolute time in @c pthread_spin_unlock @c pthread_testcancel @c pthread_yield + +@node Restartable Sequences +@section Restartable Sequences +@cindex rseq + +This section describes @theglibc{} Restartable Sequences integration. + +@deftypevar {struct rseq} __rseq_abi +@standards{GNU, sys/rseq.h} +@Theglibc{} implements a @code{__rseq_abi} TLS symbol to interact with the +Restartable Sequences system call (Linux-specific). The layout of this +structure is defined by the Linux kernel @file{linux/rseq.h} UAPI. +Registration of each thread's @code{__rseq_abi} is performed by +@theglibc{} at libc initialization and pthread creation. +@end deftypevar + +@deftypevr Macro int RSEQ_SIG +@standards{GNU, sys/rseq.h} +Each supported architecture provide a @code{RSEQ_SIG} macro in +@file{sys/rseq.h} which contains a signature. That signature is expected to be +present in the code before each Restartable Sequences abort handler. Failure +to provide the expected signature may terminate the process with a Segmentation +fault. +@end deftypevr diff --git a/misc/rseq-internal.h b/misc/rseq-internal.h new file mode 100644 index 0000000000..d564cf1bc3 --- /dev/null +++ b/misc/rseq-internal.h @@ -0,0 +1,33 @@ +/* Restartable Sequences internal API. Stub version. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef RSEQ_INTERNAL_H +#define RSEQ_INTERNAL_H + +static inline int +rseq_register_current_thread (void) +{ + return -1; +} + +static inline int +rseq_unregister_current_thread (void) +{ + return -1; +} + +#endif /* rseq-internal.h */ diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c index afd379e89a..1ff248042e 100644 --- a/nptl/pthread_create.c +++ b/nptl/pthread_create.c @@ -33,6 +33,7 @@ #include #include #include +#include #include "libioP.h" #include @@ -384,6 +385,9 @@ START_THREAD_DEFN /* Initialize pointers to locale data. */ __ctype_init (); + /* Register rseq TLS to the kernel. */ + (void) rseq_register_current_thread (); + #ifndef __ASSUME_SET_ROBUST_LIST if (__set_robust_list_avail >= 0) #endif @@ -578,6 +582,14 @@ START_THREAD_DEFN process is really dead since 'clone' got passed the CLONE_CHILD_CLEARTID flag. The 'tid' field in the TCB will be set to zero. + rseq TLS is still registered at this point. Rely on implicit unregistration + performed by the kernel on thread teardown. This is not a problem because the + rseq TLS lives on the stack, and the stack outlives the thread. If TCB + allocation is ever changed, additional steps may be required, such as + performing explicit rseq unregistration before reclaiming the rseq TLS area + memory. It is NOT sufficient to block signals because the kernel may write + to the rseq area even without signals. + The exit code is zero since in case all threads exit by calling 'pthread_exit' the exit status must be 0 (zero). */ __exit_thread (); diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile index 60dc5cf9e5..6c6f669d21 100644 --- a/sysdeps/unix/sysv/linux/Makefile +++ b/sysdeps/unix/sysv/linux/Makefile @@ -41,7 +41,7 @@ update-syscall-lists: arch-syscall.h endif ifeq ($(subdir),csu) -sysdep_routines += errno-loc +sysdep_routines += errno-loc rseq-sym endif ifeq ($(subdir),assert) @@ -92,7 +92,8 @@ sysdep_headers += sys/mount.h sys/acct.h sys/sysctl.h \ bits/termios-baud.h bits/termios-c_cflag.h \ bits/termios-c_lflag.h bits/termios-tcflow.h \ bits/termios-misc.h \ - bits/ipc-perm.h + bits/ipc-perm.h \ + sys/rseq.h bits/rseq.h tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \ tst-quota tst-sync_file_range tst-sysconf-iov_max tst-ttyname \ diff --git a/sysdeps/unix/sysv/linux/Versions b/sysdeps/unix/sysv/linux/Versions index d385085c61..52ca223ab2 100644 --- a/sysdeps/unix/sysv/linux/Versions +++ b/sysdeps/unix/sysv/linux/Versions @@ -177,6 +177,9 @@ libc { GLIBC_2.30 { getdents64; gettid; tgkill; } + GLIBC_2.32 { + __rseq_abi; + } GLIBC_PRIVATE { # functions used in other libraries __syscall_rt_sigqueueinfo; diff --git a/sysdeps/unix/sysv/linux/aarch64/bits/rseq.h b/sysdeps/unix/sysv/linux/aarch64/bits/rseq.h new file mode 100644 index 0000000000..e272c30446 --- /dev/null +++ b/sysdeps/unix/sysv/linux/aarch64/bits/rseq.h @@ -0,0 +1,43 @@ +/* Restartable Sequences Linux aarch64 architecture header. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _SYS_RSEQ_H +# error "Never use directly; include instead." +#endif + +/* RSEQ_SIG is a signature required before each abort handler code. + + It is a 32-bit value that maps to actual architecture code compiled + into applications and libraries. It needs to be defined for each + architecture. When choosing this value, it needs to be taken into + account that generating invalid instructions may have ill effects on + tools like objdump, and may also have impact on the CPU speculative + execution efficiency in some cases. + + aarch64 -mbig-endian generates mixed endianness code vs data: + little-endian code and big-endian data. Ensure the RSEQ_SIG signature + matches code endianness. */ + +#define RSEQ_SIG_CODE 0xd428bc00 /* BRK #0x45E0. */ + +#ifdef __AARCH64EB__ +#define RSEQ_SIG_DATA 0x00bc28d4 /* BRK #0x45E0. */ +#else +#define RSEQ_SIG_DATA RSEQ_SIG_CODE +#endif + +#define RSEQ_SIG RSEQ_SIG_DATA diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist index a4c31932cb..fa0702d4ac 100644 --- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist +++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist @@ -2145,3 +2145,4 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist index e7f2174ac2..482c486272 100644 --- a/sysdeps/unix/sysv/linux/alpha/libc.abilist +++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist @@ -2225,6 +2225,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 _IO_fprintf F GLIBC_2.4 _IO_printf F GLIBC_2.4 _IO_sprintf F diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist index b152c0e24a..753f643c3b 100644 --- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist +++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist @@ -133,6 +133,7 @@ GLIBC_2.30 twalk_r F GLIBC_2.31 msgctl F GLIBC_2.31 semctl F GLIBC_2.31 shmctl F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 _Exit F GLIBC_2.4 _IO_2_1_stderr_ D 0xa0 GLIBC_2.4 _IO_2_1_stdin_ D 0xa0 diff --git a/sysdeps/unix/sysv/linux/arm/bits/rseq.h b/sysdeps/unix/sysv/linux/arm/bits/rseq.h new file mode 100644 index 0000000000..45a2118dbc --- /dev/null +++ b/sysdeps/unix/sysv/linux/arm/bits/rseq.h @@ -0,0 +1,83 @@ +/* Restartable Sequences Linux arm architecture header. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _SYS_RSEQ_H +# error "Never use directly; include instead." +#endif + +/* + RSEQ_SIG is a signature required before each abort handler code. + + It is a 32-bit value that maps to actual architecture code compiled + into applications and libraries. It needs to be defined for each + architecture. When choosing this value, it needs to be taken into + account that generating invalid instructions may have ill effects on + tools like objdump, and may also have impact on the CPU speculative + execution efficiency in some cases. + + - ARM little endian + + RSEQ_SIG uses the udf A32 instruction with an uncommon immediate operand + value 0x5de3. This traps if user-space reaches this instruction by mistake, + and the uncommon operand ensures the kernel does not move the instruction + pointer to attacker-controlled code on rseq abort. + + The instruction pattern in the A32 instruction set is: + + e7f5def3 udf #24035 ; 0x5de3 + + This translates to the following instruction pattern in the T16 instruction + set: + + little endian: + def3 udf #243 ; 0xf3 + e7f5 b.n <7f5> + + - ARMv6+ big endian (BE8): + + ARMv6+ -mbig-endian generates mixed endianness code vs data: little-endian + code and big-endian data. The data value of the signature needs to have its + byte order reversed to generate the trap instruction: + + Data: 0xf3def5e7 + + Translates to this A32 instruction pattern: + + e7f5def3 udf #24035 ; 0x5de3 + + Translates to this T16 instruction pattern: + + def3 udf #243 ; 0xf3 + e7f5 b.n <7f5> + + - Prior to ARMv6 big endian (BE32): + + Prior to ARMv6, -mbig-endian generates big-endian code and data + (which match), so the endianness of the data representation of the + signature should not be reversed. However, the choice between BE32 + and BE8 is done by the linker, so we cannot know whether code and + data endianness will be mixed before the linker is invoked. So rather + than try to play tricks with the linker, the rseq signature is simply + data (not a trap instruction) prior to ARMv6 on big endian. This is + why the signature is expressed as data (.word) rather than as + instruction (.inst) in assembler. */ + +#ifdef __ARMEB__ +#define RSEQ_SIG 0xf3def5e7 /* udf #24035 ; 0x5de3 (ARMv6+) */ +#else +#define RSEQ_SIG 0xe7f5def3 /* udf #24035 ; 0x5de3 */ +#endif diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist index 9371927927..97b1081fa5 100644 --- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist +++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist @@ -130,6 +130,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 _Exit F GLIBC_2.4 _IO_2_1_stderr_ D 0xa0 GLIBC_2.4 _IO_2_1_stdin_ D 0xa0 diff --git a/sysdeps/unix/sysv/linux/bits/rseq.h b/sysdeps/unix/sysv/linux/bits/rseq.h new file mode 100644 index 0000000000..b8a63ed26d --- /dev/null +++ b/sysdeps/unix/sysv/linux/bits/rseq.h @@ -0,0 +1,29 @@ +/* Restartable Sequences architecture header. Stub version. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _SYS_RSEQ_H +# error "Never use directly; include instead." +#endif + +/* RSEQ_SIG is a signature required before each abort handler code. + + It is a 32-bit value that maps to actual architecture code compiled + into applications and libraries. It needs to be defined for each + architecture. When choosing this value, it needs to be taken into + account that generating invalid instructions may have ill effects on + tools like objdump, and may also have impact on the CPU speculative + execution efficiency in some cases. */ diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist index 9b3cee65bb..ed94510f23 100644 --- a/sysdeps/unix/sysv/linux/csky/libc.abilist +++ b/sysdeps/unix/sysv/linux/csky/libc.abilist @@ -2089,3 +2089,4 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist index df6d96fbae..3d60443799 100644 --- a/sysdeps/unix/sysv/linux/hppa/libc.abilist +++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist @@ -2046,6 +2046,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist index fcb625b6bf..15f0baa54f 100644 --- a/sysdeps/unix/sysv/linux/i386/libc.abilist +++ b/sysdeps/unix/sysv/linux/i386/libc.abilist @@ -2212,6 +2212,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist index cb556c5998..8944cb2cc8 100644 --- a/sysdeps/unix/sysv/linux/ia64/libc.abilist +++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist @@ -2078,6 +2078,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist index 5e3cdea246..ae100260b9 100644 --- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist +++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist @@ -134,6 +134,7 @@ GLIBC_2.30 twalk_r F GLIBC_2.31 msgctl F GLIBC_2.31 semctl F GLIBC_2.31 shmctl F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 _Exit F GLIBC_2.4 _IO_2_1_stderr_ D 0x98 GLIBC_2.4 _IO_2_1_stdin_ D 0x98 diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist index ea5e7a41af..c2b3f91d17 100644 --- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist +++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist @@ -2158,6 +2158,7 @@ GLIBC_2.30 twalk_r F GLIBC_2.31 msgctl F GLIBC_2.31 semctl F GLIBC_2.31 shmctl F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist index ac55b0acd7..ba9ebeae22 100644 --- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist +++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist @@ -2140,3 +2140,4 @@ GLIBC_2.30 twalk_r F GLIBC_2.31 msgctl F GLIBC_2.31 semctl F GLIBC_2.31 shmctl F +GLIBC_2.32 __rseq_abi T 0x20 diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist index f7ced487f7..a1f4f9a1c2 100644 --- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist +++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist @@ -2137,3 +2137,4 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 diff --git a/sysdeps/unix/sysv/linux/mips/bits/rseq.h b/sysdeps/unix/sysv/linux/mips/bits/rseq.h new file mode 100644 index 0000000000..4eee59265a --- /dev/null +++ b/sysdeps/unix/sysv/linux/mips/bits/rseq.h @@ -0,0 +1,62 @@ +/* Restartable Sequences Linux mips architecture header. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _SYS_RSEQ_H +# error "Never use directly; include instead." +#endif + +/* RSEQ_SIG is a signature required before each abort handler code. + + It is a 32-bit value that maps to actual architecture code compiled + into applications and libraries. It needs to be defined for each + architecture. When choosing this value, it needs to be taken into + account that generating invalid instructions may have ill effects on + tools like objdump, and may also have impact on the CPU speculative + execution efficiency in some cases. + + RSEQ_SIG uses the break instruction. The instruction pattern is: + + On MIPS: + 0350000d break 0x350 + + On nanoMIPS: + 00100350 break 0x350 + + On microMIPS: + 0000d407 break 0x350 + + For nanoMIPS32 and microMIPS, the instruction stream is encoded as + 16-bit halfwords, so the signature halfwords need to be swapped + accordingly for little-endian. */ + +#if defined(__nanomips__) +# ifdef __MIPSEL__ +# define RSEQ_SIG 0x03500010 +# else +# define RSEQ_SIG 0x00100350 +# endif +#elif defined(__mips_micromips) +# ifdef __MIPSEL__ +# define RSEQ_SIG 0xd4070000 +# else +# define RSEQ_SIG 0x0000d407 +# endif +#elif defined(__mips__) +# define RSEQ_SIG 0x0350000d +#else +/* Unknown MIPS architecture. */ +#endif diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist index 06c2e64edd..333229c27a 100644 --- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist +++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist @@ -2129,6 +2129,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist index bdfd073b86..17772e9a40 100644 --- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist +++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist @@ -2127,6 +2127,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist index 3d61d4974a..497203cd44 100644 --- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist +++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist @@ -2135,6 +2135,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist index 675acca5db..f5f48ce5c6 100644 --- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist +++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist @@ -2129,6 +2129,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist index 7fec0c9670..4152f4f734 100644 --- a/sysdeps/unix/sysv/linux/nios2/libc.abilist +++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist @@ -2178,3 +2178,4 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 diff --git a/sysdeps/unix/sysv/linux/powerpc/bits/rseq.h b/sysdeps/unix/sysv/linux/powerpc/bits/rseq.h new file mode 100644 index 0000000000..9d10000a6e --- /dev/null +++ b/sysdeps/unix/sysv/linux/powerpc/bits/rseq.h @@ -0,0 +1,37 @@ +/* Restartable Sequences Linux powerpc architecture header. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _SYS_RSEQ_H +# error "Never use directly; include instead." +#endif + +/* RSEQ_SIG is a signature required before each abort handler code. + + It is a 32-bit value that maps to actual architecture code compiled + into applications and libraries. It needs to be defined for each + architecture. When choosing this value, it needs to be taken into + account that generating invalid instructions may have ill effects on + tools like objdump, and may also have impact on the CPU speculative + execution efficiency in some cases. + + RSEQ_SIG uses the following trap instruction: + + powerpc-be: 0f e5 00 0b twui r5,11 + powerpc64-le: 0b 00 e5 0f twui r5,11 + powerpc64-be: 0f e5 00 0b twui r5,11 */ + +#define RSEQ_SIG 0x0fe5000b diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist index 1e8ff6f83e..210d1795c1 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist @@ -2185,6 +2185,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 _IO_fprintf F GLIBC_2.4 _IO_printf F GLIBC_2.4 _IO_sprintf F diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist index b5a0751d90..6a3cde5fb6 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist @@ -2218,6 +2218,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 _IO_fprintf F GLIBC_2.4 _IO_printf F GLIBC_2.4 _IO_sprintf F diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist index 0c86217fc6..4f243acb2a 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist @@ -2048,6 +2048,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 _IO_fprintf F GLIBC_2.4 _IO_printf F GLIBC_2.4 _IO_sprintf F diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist index 2229a1dcc0..99d836bc11 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist @@ -2247,3 +2247,4 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist index 31010e6cf7..7694392cd5 100644 --- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist +++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist @@ -2107,3 +2107,4 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h new file mode 100644 index 0000000000..5f7f02f1ec --- /dev/null +++ b/sysdeps/unix/sysv/linux/rseq-internal.h @@ -0,0 +1,73 @@ +/* Restartable Sequences internal API. Linux implementation. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef RSEQ_INTERNAL_H +#define RSEQ_INTERNAL_H + +#include +#include +#include +#include + +#ifdef RSEQ_SIG + +static inline int +rseq_register_current_thread (void) +{ + int rc, ret = 0; + + if (__rseq_abi.cpu_id == RSEQ_CPU_ID_REGISTRATION_FAILED) + return -1; + rc = INTERNAL_SYSCALL_CALL (rseq, &__rseq_abi, sizeof (struct rseq), + 0, RSEQ_SIG); + if (!rc) + goto end; + if (INTERNAL_SYSCALL_ERRNO (rc) != EBUSY) + __rseq_abi.cpu_id = RSEQ_CPU_ID_REGISTRATION_FAILED; + ret = -1; +end: + return ret; +} + +static inline int +rseq_unregister_current_thread (void) +{ + int rc, ret = 0; + + rc = INTERNAL_SYSCALL_CALL (rseq, &__rseq_abi, sizeof (struct rseq), + RSEQ_FLAG_UNREGISTER, RSEQ_SIG); + if (!rc) + goto end; + ret = -1; +end: + return ret; +} +#else +static inline int +rseq_register_current_thread (void) +{ + return -1; +} + +static inline int +rseq_unregister_current_thread (void) +{ + return -1; +} +#endif + +#endif /* rseq-internal.h */ diff --git a/sysdeps/unix/sysv/linux/rseq-sym.c b/sysdeps/unix/sysv/linux/rseq-sym.c new file mode 100644 index 0000000000..0e33fab278 --- /dev/null +++ b/sysdeps/unix/sysv/linux/rseq-sym.c @@ -0,0 +1,25 @@ +/* Restartable Sequences exported symbols. Linux Implementation. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include + +__thread struct rseq __rseq_abi = { + .cpu_id = RSEQ_CPU_ID_UNINITIALIZED, +}; diff --git a/sysdeps/unix/sysv/linux/s390/bits/rseq.h b/sysdeps/unix/sysv/linux/s390/bits/rseq.h new file mode 100644 index 0000000000..c25ee67ee7 --- /dev/null +++ b/sysdeps/unix/sysv/linux/s390/bits/rseq.h @@ -0,0 +1,37 @@ +/* Restartable Sequences Linux s390 architecture header. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _SYS_RSEQ_H +# error "Never use directly; include instead." +#endif + +/* RSEQ_SIG is a signature required before each abort handler code. + + It is a 32-bit value that maps to actual architecture code compiled + into applications and libraries. It needs to be defined for each + architecture. When choosing this value, it needs to be taken into + account that generating invalid instructions may have ill effects on + tools like objdump, and may also have impact on the CPU speculative + execution efficiency in some cases. + + RSEQ_SIG uses the trap4 instruction. As Linux does not make use of the + access-register mode nor the linkage stack this instruction will always + cause a special-operation exception (the trap-enabled bit in the DUCT + is and will stay 0). The instruction pattern is + b2 ff 0f ff trap4 4095(%r0) */ + +#define RSEQ_SIG 0xB2FF0FFF diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist index 4feca641b0..eb49d11cd1 100644 --- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist +++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist @@ -2183,6 +2183,7 @@ GLIBC_2.30 twalk_r F GLIBC_2.31 msgctl F GLIBC_2.31 semctl F GLIBC_2.31 shmctl F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 _IO_fprintf F GLIBC_2.4 _IO_printf F GLIBC_2.4 _IO_sprintf F diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist index efe588a072..442f7e33a8 100644 --- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist +++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist @@ -2084,6 +2084,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 _IO_fprintf F GLIBC_2.4 _IO_printf F GLIBC_2.4 _IO_sprintf F diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist index 6bfc2b7439..f47ec14735 100644 --- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist +++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist @@ -2053,6 +2053,7 @@ GLIBC_2.30 twalk_r F GLIBC_2.31 msgctl F GLIBC_2.31 semctl F GLIBC_2.31 shmctl F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist index 4b057bf4a2..8b4557d325 100644 --- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist +++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist @@ -2050,6 +2050,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist index 49cd597fd6..52f951c4fe 100644 --- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist +++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist @@ -2174,6 +2174,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 _IO_fprintf F GLIBC_2.4 _IO_printf F GLIBC_2.4 _IO_sprintf F diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist index 95e68e0ba1..2b59f52de0 100644 --- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist @@ -2101,6 +2101,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/sys/rseq.h b/sysdeps/unix/sysv/linux/sys/rseq.h new file mode 100644 index 0000000000..503dce4cac --- /dev/null +++ b/sysdeps/unix/sysv/linux/sys/rseq.h @@ -0,0 +1,186 @@ +/* Restartable Sequences exported symbols. Linux header. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _SYS_RSEQ_H +#define _SYS_RSEQ_H 1 + +/* Architecture-specific rseq signature. */ +#include +#include +#include + +#ifdef __has_include +# if __has_include ("linux/rseq.h") +# define __GLIBC_HAVE_KERNEL_RSEQ +# endif +#else +# include +# if LINUX_VERSION_CODE >= KERNEL_VERSION (4, 18, 0) +# define __GLIBC_HAVE_KERNEL_RSEQ +# endif +#endif + +#ifdef __GLIBC_HAVE_KERNEL_RSEQ +/* We use the structures declarations from the kernel headers. */ +# include +#else +/* We use a copy of the include/uapi/linux/rseq.h kernel header. */ + +#include + +enum rseq_cpu_id_state + { + RSEQ_CPU_ID_UNINITIALIZED = -1, + RSEQ_CPU_ID_REGISTRATION_FAILED = -2, + }; + +enum rseq_flags + { + RSEQ_FLAG_UNREGISTER = (1 << 0), + }; + +enum rseq_cs_flags_bit + { + RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT = 0, + RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT = 1, + RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT = 2, + }; + +enum rseq_cs_flags + { + RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT = + (1U << RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT), + RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL = + (1U << RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT), + RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE = + (1U << RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT), + }; + +/* struct rseq_cs is aligned on 4 * 8 bytes to ensure it is always + contained within a single cache-line. It is usually declared as + link-time constant data. */ +struct rseq_cs + { + /* Version of this structure. */ + uint32_t version; + /* enum rseq_cs_flags. */ + uint32_t flags; + uint64_t start_ip; + /* Offset from start_ip. */ + uint64_t post_commit_offset; + uint64_t abort_ip; +} __attribute__((aligned(4 * sizeof(uint64_t)))); + +/* struct rseq is aligned on 4 * 8 bytes to ensure it is always + contained within a single cache-line. + + A single struct rseq per thread is allowed. */ +struct rseq + { + /* Restartable sequences cpu_id_start field. Updated by the + kernel. Read by user-space with single-copy atomicity + semantics. This field should only be read by the thread which + registered this data structure. Aligned on 32-bit. Always + contains a value in the range of possible CPUs, although the + value may not be the actual current CPU (e.g. if rseq is not + initialized). This CPU number value should always be compared + against the value of the cpu_id field before performing a rseq + commit or returning a value read from a data structure indexed + using the cpu_id_start value. */ + uint32_t cpu_id_start; + /* Restartable sequences cpu_id field. Updated by the kernel. + Read by user-space with single-copy atomicity semantics. This + field should only be read by the thread which registered this + data structure. Aligned on 32-bit. Values + RSEQ_CPU_ID_UNINITIALIZED and RSEQ_CPU_ID_REGISTRATION_FAILED + have a special semantic: the former means "rseq uninitialized", + and latter means "rseq initialization failed". This value is + meant to be read within rseq critical sections and compared + with the cpu_id_start value previously read, before performing + the commit instruction, or read and compared with the + cpu_id_start value before returning a value loaded from a data + structure indexed using the cpu_id_start value. */ + uint32_t cpu_id; + /* Restartable sequences rseq_cs field. + + Contains NULL when no critical section is active for the current + thread, or holds a pointer to the currently active struct rseq_cs. + + Updated by user-space, which sets the address of the currently + active rseq_cs at the beginning of assembly instruction sequence + block, and set to NULL by the kernel when it restarts an assembly + instruction sequence block, as well as when the kernel detects that + it is preempting or delivering a signal outside of the range + targeted by the rseq_cs. Also needs to be set to NULL by user-space + before reclaiming memory that contains the targeted struct rseq_cs. + + Read and set by the kernel. Set by user-space with single-copy + atomicity semantics. This field should only be updated by the + thread which registered this data structure. Aligned on 64-bit. */ + union { + uint64_t ptr64; +#ifdef __LP64__ + uint64_t ptr; +#else + struct { +#if (defined(__BYTE_ORDER) && (__BYTE_ORDER == __BIG_ENDIAN)) || defined(__BIG_ENDIAN) + uint32_t padding; /* Initialized to zero. */ + uint32_t ptr32; +#else /* LITTLE */ + uint32_t ptr32; + uint32_t padding; /* Initialized to zero. */ +#endif /* ENDIAN */ + } ptr; +#endif + } rseq_cs; + + /* Restartable sequences flags field. + + This field should only be updated by the thread which + registered this data structure. Read by the kernel. + Mainly used for single-stepping through rseq critical sections + with debuggers. + + - RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT + Inhibit instruction sequence block restart on preemption + for this thread. + - RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL + Inhibit instruction sequence block restart on signal + delivery for this thread. + - RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE + Inhibit instruction sequence block restart on migration for + this thread. */ + uint32_t flags; + } __attribute__((aligned(4 * sizeof(uint64_t)))); + +#endif + +/* Ensure the compiler supports __attribute__ ((aligned)). */ +_Static_assert (__alignof__ (struct rseq_cs) >= 4 * sizeof(uint64_t), + "alignment"); +_Static_assert (__alignof__ (struct rseq) >= 4 * sizeof(uint64_t), + "alignment"); + +/* Allocations of struct rseq and struct rseq_cs on the heap need to + be aligned on 32 bytes. Therefore, use of malloc is discouraged + because it does not guarantee alignment. posix_memalign should be + used instead. */ + +extern __thread struct rseq __rseq_abi +__attribute__ ((tls_model ("initial-exec"))); + +#endif /* sys/rseq.h */ diff --git a/sysdeps/unix/sysv/linux/x86/bits/rseq.h b/sysdeps/unix/sysv/linux/x86/bits/rseq.h new file mode 100644 index 0000000000..75f52d9788 --- /dev/null +++ b/sysdeps/unix/sysv/linux/x86/bits/rseq.h @@ -0,0 +1,30 @@ +/* Restartable Sequences Linux x86 architecture header. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _SYS_RSEQ_H +# error "Never use directly; include instead." +#endif + +/* RSEQ_SIG is a signature required before each abort handler code. + + RSEQ_SIG is used with the following reserved undefined instructions, which + trap in user-space: + + x86-32: 0f b9 3d 53 30 05 53 ud1 0x53053053,%edi + x86-64: 0f b9 3d 53 30 05 53 ud1 0x53053053(%rip),%edi */ + +#define RSEQ_SIG 0x53053053 diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist index 1f2dbd1451..dfa3fe85ef 100644 --- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist +++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist @@ -2059,6 +2059,7 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 GLIBC_2.4 __confstr_chk F GLIBC_2.4 __fgets_chk F GLIBC_2.4 __fgets_unlocked_chk F diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist index 59da85a5d8..6ff082ee4e 100644 --- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist +++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist @@ -2158,3 +2158,4 @@ GLIBC_2.30 getdents64 F GLIBC_2.30 gettid F GLIBC_2.30 tgkill F GLIBC_2.30 twalk_r F +GLIBC_2.32 __rseq_abi T 0x20 From patchwork Thu Mar 26 15:56:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: develop--- via Libc-alpha X-Patchwork-Id: 1262093 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=8.43.85.97; helo=sourceware.org; envelope-from=libc-alpha-bounces@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=sourceware.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=RUXFycLM; dkim-atps=neutral Received: from sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 48p8l11hl9z9sRY for ; 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Thu, 26 Mar 2020 11:57:05 -0400 (EDT) Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id Ii5h1qGZ6RL3; Thu, 26 Mar 2020 11:57:05 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 7FD412772CF; Thu, 26 Mar 2020 11:57:00 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 7FD412772CF X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id P1cMScfDNFqm; Thu, 26 Mar 2020 11:57:00 -0400 (EDT) Received: from localhost.localdomain (192-222-181-218.qc.cable.ebox.net [192.222.181.218]) by mail.efficios.com (Postfix) with ESMTPSA id 06F282777E1; Thu, 26 Mar 2020 11:56:58 -0400 (EDT) To: Carlos O'Donell Subject: [PATCH glibc 6/9] glibc: sched_getcpu(): use rseq cpu_id TLS on Linux (v7) Date: Thu, 26 Mar 2020 11:56:30 -0400 Message-Id: <20200326155633.18236-7-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> References: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> X-Spam-Status: No, score=-30.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mathieu Desnoyers via Libc-alpha From: develop--- via Libc-alpha Reply-To: Mathieu Desnoyers Cc: libc-alpha@sourceware.org, linux-api@vger.kernel.org, Boqun Feng , Will Deacon , linux-kernel@vger.kernel.org, Peter Zijlstra , Ben Maurer , Mathieu Desnoyers , Thomas Gleixner , "Paul E. McKenney" , Paul Turner , Joseph Myers Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" When available, use the cpu_id field from __rseq_abi on Linux to implement sched_getcpu(). Fall-back on the vgetcpu vDSO if unavailable. Benchmarks: x86-64: Intel E5-2630 v3@2.40GHz, 16-core, hyperthreading glibc sched_getcpu(): 13.7 ns (baseline) glibc sched_getcpu() using rseq: 2.5 ns (speedup: 5.5x) inline load cpuid from __rseq_abi TLS: 0.8 ns (speedup: 17.1x) Signed-off-by: Mathieu Desnoyers CC: Carlos O'Donell CC: Florian Weimer CC: Joseph Myers CC: Szabolcs Nagy CC: Thomas Gleixner CC: Ben Maurer CC: Peter Zijlstra CC: "Paul E. McKenney" CC: Boqun Feng CC: Will Deacon CC: Paul Turner CC: libc-alpha@sourceware.org CC: linux-kernel@vger.kernel.org CC: linux-api@vger.kernel.org --- Changes since v1: - rseq is only used if both __NR_rseq and RSEQ_SIG are defined. Changes since v2: - remove duplicated __rseq_abi extern declaration. Changes since v3: - update ChangeLog. Changes since v4: - Use atomic_load_relaxed to load the __rseq_abi.cpu_id field, a consequence of the fact that __rseq_abi is not volatile anymore. - Include atomic.h which provides atomic_load_relaxed. Changes since v5: - Use __ASSUME_RSEQ to detect rseq availability. Changes since v6: - Remove use of __ASSUME_RSEQ. --- sysdeps/unix/sysv/linux/sched_getcpu.c | 27 ++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) diff --git a/sysdeps/unix/sysv/linux/sched_getcpu.c b/sysdeps/unix/sysv/linux/sched_getcpu.c index c019cfb3cf..2269c4f2bd 100644 --- a/sysdeps/unix/sysv/linux/sched_getcpu.c +++ b/sysdeps/unix/sysv/linux/sched_getcpu.c @@ -18,10 +18,15 @@ #include #include #include +#include #include -int -sched_getcpu (void) +#ifdef HAVE_GETCPU_VSYSCALL +# define HAVE_VSYSCALL +#endif + +static int +vsyscall_sched_getcpu (void) { unsigned int cpu; int r = -1; @@ -32,3 +37,21 @@ sched_getcpu (void) #endif return r == -1 ? r : cpu; } + +#include + +#ifdef RSEQ_SIG +int +sched_getcpu (void) +{ + int cpu_id = atomic_load_relaxed (&__rseq_abi.cpu_id); + + return cpu_id >= 0 ? cpu_id : vsyscall_sched_getcpu (); +} +#else +int +sched_getcpu (void) +{ + return vsyscall_sched_getcpu (); +} +#endif From patchwork Thu Mar 26 15:56:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: develop--- via Libc-alpha X-Patchwork-Id: 1262092 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=8.43.85.97; helo=sourceware.org; envelope-from=libc-alpha-bounces@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=sourceware.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=yP0QPGbB; dkim-atps=neutral Received: from sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 48p8kw5BGWz9sRY for ; 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Thu, 26 Mar 2020 11:57:05 -0400 (EDT) Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id hiA2Vs_1JuF1; Thu, 26 Mar 2020 11:57:05 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id A6B11277D40; Thu, 26 Mar 2020 11:57:00 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com A6B11277D40 X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id ahnDqlBYAei3; Thu, 26 Mar 2020 11:57:00 -0400 (EDT) Received: from localhost.localdomain (192-222-181-218.qc.cable.ebox.net [192.222.181.218]) by mail.efficios.com (Postfix) with ESMTPSA id 42FB9277D3F; Thu, 26 Mar 2020 11:56:58 -0400 (EDT) To: Carlos O'Donell Subject: [PATCH glibc 7/9] support record failure: allow use from constructor Date: Thu, 26 Mar 2020 11:56:31 -0400 Message-Id: <20200326155633.18236-8-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> References: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> X-Spam-Status: No, score=-30.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mathieu Desnoyers via Libc-alpha From: develop--- via Libc-alpha Reply-To: Mathieu Desnoyers Cc: libc-alpha@sourceware.org, Joseph Myers , Mathieu Desnoyers Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" Expose support_record_failure_init () so constructors can explicitly initialize the record failure API. This is preferred to lazy initialization at first use, because lazy initialization does not cover use in constructors within forked children processes (forked from parent constructor). Signed-off-by: Mathieu Desnoyers Reviewed-by: Carlos O'Donell CC: Carlos O'Donell CC: Florian Weimer CC: Joseph Myers CC: Szabolcs Nagy CC: libc-alpha@sourceware.org --- support/check.h | 4 ++++ support/support_record_failure.c | 18 +++++++++++++----- 2 files changed, 17 insertions(+), 5 deletions(-) diff --git a/support/check.h b/support/check.h index 77d1d1e14d..902cea6878 100644 --- a/support/check.h +++ b/support/check.h @@ -88,6 +88,10 @@ void support_test_verify_exit_impl (int status, const char *file, int line, does not support reporting failures from a DSO. */ void support_record_failure (void); +/* Initialize record failure. Calling this is only needed when + recording failures from constructors. */ +void support_record_failure_init (void); + /* Static assertion, under a common name for both C++ and C11. */ #ifdef __cplusplus # define support_static_assert static_assert diff --git a/support/support_record_failure.c b/support/support_record_failure.c index f766c06236..957572f487 100644 --- a/support/support_record_failure.c +++ b/support/support_record_failure.c @@ -32,8 +32,12 @@ zero, the failure of a test can be detected. The init constructor function below puts *state on a shared - annonymous mapping, so that failure reports from subprocesses - propagate to the parent process. */ + anonymous mapping, so that failure reports from subprocesses + propagate to the parent process. + + support_record_failure_init is exposed so it can be called explicitly + in case this API needs to be used from a constructor. */ + struct test_failures { unsigned int counter; @@ -41,10 +45,14 @@ struct test_failures }; static struct test_failures *state; -static __attribute__ ((constructor)) void -init (void) +__attribute__ ((constructor)) void +support_record_failure_init (void) { - void *ptr = mmap (NULL, sizeof (*state), PROT_READ | PROT_WRITE, + void *ptr; + + if (state != NULL) + return; + ptr = mmap (NULL, sizeof (*state), PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_SHARED, -1, 0); if (ptr == MAP_FAILED) { From patchwork Thu Mar 26 15:56:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: develop--- via Libc-alpha X-Patchwork-Id: 1262095 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; 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Thu, 26 Mar 2020 11:57:05 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id EB7C3277CB0; Thu, 26 Mar 2020 11:57:02 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com EB7C3277CB0 X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id bhPDd7LTur46; Thu, 26 Mar 2020 11:57:02 -0400 (EDT) Received: from localhost.localdomain (192-222-181-218.qc.cable.ebox.net [192.222.181.218]) by mail.efficios.com (Postfix) with ESMTPSA id 6B7F1277BEE; Thu, 26 Mar 2020 11:56:58 -0400 (EDT) To: Carlos O'Donell Subject: [PATCH glibc 8/9] support: implement xpthread key create/delete (v4) Date: Thu, 26 Mar 2020 11:56:32 -0400 Message-Id: <20200326155633.18236-9-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> References: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> X-Spam-Status: No, score=-30.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mathieu Desnoyers via Libc-alpha From: develop--- via Libc-alpha Reply-To: Mathieu Desnoyers Cc: libc-alpha@sourceware.org, Joseph Myers , Mathieu Desnoyers Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" Expose xpthread_key_create () and xpthread_key_delete () wrappers for tests. Signed-off-by: Mathieu Desnoyers CC: Carlos O'Donell CC: Florian Weimer CC: Joseph Myers CC: Szabolcs Nagy CC: libc-alpha@sourceware.org --- Changes since v1: - Update ChangeLog. - Wrap long line in xpthread_key_create. Changes since v2: - Rebase on glibc 2.30. Changes since v3: - Update copyright range to include 2020. --- support/Makefile | 2 ++ support/xpthread_key_create.c | 25 +++++++++++++++++++++++++ support/xpthread_key_delete.c | 24 ++++++++++++++++++++++++ support/xthread.h | 2 ++ 4 files changed, 53 insertions(+) create mode 100644 support/xpthread_key_create.c create mode 100644 support/xpthread_key_delete.c diff --git a/support/Makefile b/support/Makefile index 6e38b87ebe..4498192a0a 100644 --- a/support/Makefile +++ b/support/Makefile @@ -130,6 +130,8 @@ libsupport-routines = \ xpthread_create \ xpthread_detach \ xpthread_join \ + xpthread_key_create \ + xpthread_key_delete \ xpthread_mutex_consistent \ xpthread_mutex_destroy \ xpthread_mutex_init \ diff --git a/support/xpthread_key_create.c b/support/xpthread_key_create.c new file mode 100644 index 0000000000..1988dee138 --- /dev/null +++ b/support/xpthread_key_create.c @@ -0,0 +1,25 @@ +/* pthread_key_create with error checking. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include + +void +xpthread_key_create (pthread_key_t *key, void (*destr_function) (void *)) +{ + xpthread_check_return ("pthread_key_create", + pthread_key_create (key, destr_function)); +} diff --git a/support/xpthread_key_delete.c b/support/xpthread_key_delete.c new file mode 100644 index 0000000000..99144512d4 --- /dev/null +++ b/support/xpthread_key_delete.c @@ -0,0 +1,24 @@ +/* pthread_key_delete with error checking. + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include + +void +xpthread_key_delete (pthread_key_t key) +{ + xpthread_check_return ("pthread_key_delete", pthread_key_delete (key)); +} diff --git a/support/xthread.h b/support/xthread.h index d350d1506d..2a519874bf 100644 --- a/support/xthread.h +++ b/support/xthread.h @@ -95,6 +95,8 @@ void xpthread_rwlock_wrlock (pthread_rwlock_t *rwlock); void xpthread_rwlock_rdlock (pthread_rwlock_t *rwlock); void xpthread_rwlock_unlock (pthread_rwlock_t *rwlock); void xpthread_rwlock_destroy (pthread_rwlock_t *rwlock); +void xpthread_key_create (pthread_key_t *key, void (*destr_function) (void *)); +void xpthread_key_delete (pthread_key_t key); __END_DECLS From patchwork Thu Mar 26 15:56:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: develop--- via Libc-alpha X-Patchwork-Id: 1262096 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; 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Thu, 26 Mar 2020 11:57:05 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id C40E32772D1; Thu, 26 Mar 2020 11:57:00 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com C40E32772D1 X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id EWp9R6CoOfei; Thu, 26 Mar 2020 11:57:00 -0400 (EDT) Received: from localhost.localdomain (192-222-181-218.qc.cable.ebox.net [192.222.181.218]) by mail.efficios.com (Postfix) with ESMTPSA id 93F802772CB; Thu, 26 Mar 2020 11:56:58 -0400 (EDT) To: Carlos O'Donell Subject: [PATCH glibc 9/9] rseq registration tests (v9) Date: Thu, 26 Mar 2020 11:56:33 -0400 Message-Id: <20200326155633.18236-10-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> References: <20200326155633.18236-1-mathieu.desnoyers@efficios.com> X-Spam-Status: No, score=-30.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Mathieu Desnoyers via Libc-alpha From: develop--- via Libc-alpha Reply-To: Mathieu Desnoyers Cc: libc-alpha@sourceware.org, Boqun Feng , Will Deacon , Peter Zijlstra , Ben Maurer , Mathieu Desnoyers , Thomas Gleixner , "Paul E. McKenney" , Paul Turner , Joseph Myers Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" These tests validate that rseq is registered from various execution contexts (main thread, constructor, destructor, other threads, other threads created from constructor and destructor, forked process (without exec), pthread_atfork handlers, pthread setspecific destructors, C++ thread and process destructors, signal handlers, atexit handlers). tst-rseq.c only links against libc.so, testing registration of rseq in a non-multithreaded environment. tst-rseq-nptl.c also links against libpthread.so, testing registration of rseq in a multithreaded environment. See the Linux kernel selftests for extensive rseq stress-tests. Signed-off-by: Mathieu Desnoyers CC: Carlos O'Donell CC: Florian Weimer CC: Joseph Myers CC: Szabolcs Nagy CC: Thomas Gleixner CC: Ben Maurer CC: Peter Zijlstra CC: "Paul E. McKenney" CC: Boqun Feng CC: Will Deacon CC: Paul Turner CC: libc-alpha@sourceware.org --- Changes since v1: - Rename tst-rseq.c to tst-rseq-nptl.c. - Introduce tst-rseq.c testing rseq registration in a non-multithreaded environment. Chances since v2: - Update file headers. - use xpthread key create/delete. - remove set stacksize. - Tests depend on both __NR_rseq and RSEQ_SIG being defined. Changes since v3: - Update ChangeLog. Changes since v4: - Remove volatile from sys_rseq() rseq_abi parameter. - Use atomic_load_relaxed to load __rseq_abi.cpu_id, consequence of the fact that __rseq_abi is not volatile anymore. - Include atomic.h from tst-rseq.c for use of atomic_load_relaxed. Move tst-rseq.c to internal tests within Makefile due to its use of atomic.h. - Test __rseq_handled initialization by glibc. Changes since v5: - Rebase on glibc 2.30. Changes since v6: - Remove __rseq_handled. Changes since v7: - Update copyright range to include 2020. - Use __ASSUME_RSEQ to detect rseq availability. Changes since v8: - Remove use of __ASSUME_RSEQ. --- sysdeps/unix/sysv/linux/Makefile | 6 +- sysdeps/unix/sysv/linux/tst-rseq-nptl.c | 347 ++++++++++++++++++++++++ sysdeps/unix/sysv/linux/tst-rseq.c | 108 ++++++++ 3 files changed, 459 insertions(+), 2 deletions(-) create mode 100644 sysdeps/unix/sysv/linux/tst-rseq-nptl.c create mode 100644 sysdeps/unix/sysv/linux/tst-rseq.c diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile index 6c6f669d21..b8f13e6d70 100644 --- a/sysdeps/unix/sysv/linux/Makefile +++ b/sysdeps/unix/sysv/linux/Makefile @@ -100,7 +100,9 @@ tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \ test-errno-linux tst-memfd_create tst-mlock2 tst-pkey \ tst-rlimit-infinity tst-ofdlocks tst-gettid tst-gettid-kill \ tst-tgkill -tests-internal += tst-ofdlocks-compat tst-sigcontext-get_pc + +tests-internal += tst-ofdlocks-compat tst-sigcontext-get_pc \ + tst-ofdlocks-compat tst-rseq CFLAGS-tst-sigcontext-get_pc.c = -fasynchronous-unwind-tables @@ -303,5 +305,5 @@ ifeq ($(subdir),nptl) tests += tst-align-clone tst-getpid1 \ tst-thread-affinity-pthread tst-thread-affinity-pthread2 \ tst-thread-affinity-sched -tests-internal += tst-setgetname +tests-internal += tst-setgetname tst-rseq-nptl endif diff --git a/sysdeps/unix/sysv/linux/tst-rseq-nptl.c b/sysdeps/unix/sysv/linux/tst-rseq-nptl.c new file mode 100644 index 0000000000..0af2589c14 --- /dev/null +++ b/sysdeps/unix/sysv/linux/tst-rseq-nptl.c @@ -0,0 +1,347 @@ +/* Restartable Sequences NPTL test. + + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +/* These tests validate that rseq is registered from various execution + contexts (main thread, constructor, destructor, other threads, other + threads created from constructor and destructor, forked process + (without exec), pthread_atfork handlers, pthread setspecific + destructors, C++ thread and process destructors, signal handlers, + atexit handlers). + + See the Linux kernel selftests for extensive rseq stress-tests. */ + +#include +#include +#include +#include +#include +#include + +#ifdef RSEQ_SIG +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static pthread_key_t rseq_test_key; + +static int +rseq_thread_registered (void) +{ + return (int32_t) atomic_load_relaxed (&__rseq_abi.cpu_id) >= 0; +} + +static int +do_rseq_main_test (void) +{ + if (raise (SIGUSR1)) + FAIL_EXIT1 ("error raising signal"); + if (pthread_setspecific (rseq_test_key, (void *) 1l)) + FAIL_EXIT1 ("error in pthread_setspecific"); + if (!rseq_thread_registered ()) + { + FAIL_RET ("rseq not registered in main thread"); + } + return 0; +} + +static void +cancel_routine (void *arg) +{ + if (!rseq_thread_registered ()) + { + printf ("rseq not registered in cancel routine\n"); + support_record_failure (); + } +} + +static int cancel_thread_ready; + +static void +test_cancel_thread (void) +{ + pthread_cleanup_push (cancel_routine, NULL); + atomic_store_release (&cancel_thread_ready, 1); + for (;;) + usleep (100); + pthread_cleanup_pop (0); +} + +static void * +thread_function (void * arg) +{ + int i = (int) (intptr_t) arg; + + if (raise (SIGUSR1)) + FAIL_EXIT1 ("error raising signal"); + if (i == 0) + test_cancel_thread (); + if (pthread_setspecific (rseq_test_key, (void *) 1l)) + FAIL_EXIT1 ("error in pthread_setspecific"); + return rseq_thread_registered () ? NULL : (void *) 1l; +} + +static void +sighandler (int sig) +{ + if (!rseq_thread_registered ()) + { + printf ("rseq not registered in signal handler\n"); + support_record_failure (); + } +} + +static void +setup_signals (void) +{ + struct sigaction sa; + + sigemptyset (&sa.sa_mask); + sigaddset (&sa.sa_mask, SIGUSR1); + sa.sa_flags = 0; + sa.sa_handler = sighandler; + if (sigaction (SIGUSR1, &sa, NULL) != 0) + { + FAIL_EXIT1 ("sigaction failure: %s", strerror (errno)); + } +} + +#define N 7 +static const int t[N] = { 1, 2, 6, 5, 4, 3, 50 }; + +static int +do_rseq_threads_test (int nr_threads) +{ + pthread_t th[nr_threads]; + int i; + int result = 0; + + cancel_thread_ready = 0; + for (i = 0; i < nr_threads; ++i) + if (pthread_create (&th[i], NULL, thread_function, + (void *) (intptr_t) i) != 0) + { + FAIL_EXIT1 ("creation of thread %d failed", i); + } + + while (!atomic_load_acquire (&cancel_thread_ready)) + usleep (100); + + if (pthread_cancel (th[0])) + FAIL_EXIT1 ("error in pthread_cancel"); + + for (i = 0; i < nr_threads; ++i) + { + void *v; + if (pthread_join (th[i], &v) != 0) + { + printf ("join of thread %d failed\n", i); + result = 1; + } + else if (i != 0 && v != NULL) + { + printf ("join %d successful, but child failed\n", i); + result = 1; + } + else if (i == 0 && v == NULL) + { + printf ("join %d successful, child did not fail as expected\n", i); + result = 1; + } + } + return result; +} + +static int +sys_rseq (struct rseq *rseq_abi, uint32_t rseq_len, int flags, uint32_t sig) +{ + return syscall (__NR_rseq, rseq_abi, rseq_len, flags, sig); +} + +static int +rseq_available (void) +{ + int rc; + + rc = sys_rseq (NULL, 0, 0, 0); + if (rc != -1) + FAIL_EXIT1 ("Unexpected rseq return value %d", rc); + switch (errno) + { + case ENOSYS: + return 0; + case EINVAL: + return 1; + default: + FAIL_EXIT1 ("Unexpected rseq error %s", strerror (errno)); + } +} + +static int +do_rseq_fork_test (void) +{ + int status; + pid_t pid, retpid; + + pid = fork (); + switch (pid) + { + case 0: + exit (do_rseq_main_test ()); + case -1: + FAIL_EXIT1 ("Unexpected fork error %s", strerror (errno)); + } + retpid = TEMP_FAILURE_RETRY (waitpid (pid, &status, 0)); + if (retpid != pid) + { + FAIL_EXIT1 ("waitpid returned %ld, expected %ld", + (long int) retpid, (long int) pid); + } + if (WEXITSTATUS (status)) + { + printf ("rseq not registered in child\n"); + return 1; + } + return 0; +} + +static int +do_rseq_test (void) +{ + int i, result = 0; + + if (!rseq_available ()) + { + FAIL_UNSUPPORTED ("kernel does not support rseq, skipping test"); + } + setup_signals (); + if (raise (SIGUSR1)) + FAIL_EXIT1 ("error raising signal"); + if (do_rseq_main_test ()) + result = 1; + for (i = 0; i < N; i++) + { + if (do_rseq_threads_test (t[i])) + result = 1; + } + if (do_rseq_fork_test ()) + result = 1; + return result; +} + +static void +atfork_prepare (void) +{ + if (!rseq_thread_registered ()) + { + printf ("rseq not registered in pthread atfork prepare\n"); + support_record_failure (); + } +} + +static void +atfork_parent (void) +{ + if (!rseq_thread_registered ()) + { + printf ("rseq not registered in pthread atfork parent\n"); + support_record_failure (); + } +} + +static void +atfork_child (void) +{ + if (!rseq_thread_registered ()) + { + printf ("rseq not registered in pthread atfork child\n"); + support_record_failure (); + } +} + +static void +rseq_key_destructor (void *arg) +{ + /* Cannot use deferred failure reporting after main () returns. */ + if (!rseq_thread_registered ()) + FAIL_EXIT1 ("rseq not registered in pthread key destructor"); +} + +static void +atexit_handler (void) +{ + /* Cannot use deferred failure reporting after main () returns. */ + if (!rseq_thread_registered ()) + FAIL_EXIT1 ("rseq not registered in atexit handler"); +} + +static void __attribute__ ((constructor)) +do_rseq_constructor_test (void) +{ + support_record_failure_init (); + if (atexit (atexit_handler)) + FAIL_EXIT1 ("error calling atexit"); + xpthread_key_create (&rseq_test_key, rseq_key_destructor); + if (pthread_atfork (atfork_prepare, atfork_parent, atfork_child)) + FAIL_EXIT1 ("error calling pthread_atfork"); + if (do_rseq_test ()) + FAIL_EXIT1 ("rseq not registered within constructor"); +} + +static void __attribute__ ((destructor)) +do_rseq_destructor_test (void) +{ + /* Cannot use deferred failure reporting after main () returns. */ + if (do_rseq_test ()) + FAIL_EXIT1 ("rseq not registered within destructor"); + xpthread_key_delete (rseq_test_key); +} + +/* Test C++ destructor called at thread and process exit. */ +void +__call_tls_dtors (void) +{ + /* Cannot use deferred failure reporting after main () returns. */ + if (!rseq_thread_registered ()) + FAIL_EXIT1 ("rseq not registered in C++ thread/process exit destructor"); +} +#else +static int +do_rseq_test (void) +{ +#ifndef RSEQ_SIG + FAIL_UNSUPPORTED ("glibc does not define RSEQ_SIG, skipping test"); +#endif + return 0; +} +#endif + +static int +do_test (void) +{ + return do_rseq_test (); +} + +#include diff --git a/sysdeps/unix/sysv/linux/tst-rseq.c b/sysdeps/unix/sysv/linux/tst-rseq.c new file mode 100644 index 0000000000..18bc9d4e21 --- /dev/null +++ b/sysdeps/unix/sysv/linux/tst-rseq.c @@ -0,0 +1,108 @@ +/* Restartable Sequences single-threaded tests. + + Copyright (C) 2019-2020 Free Software Foundation, Inc. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +/* These tests validate that rseq is registered from main in an executable + not linked against libpthread. */ + +#include +#include +#include +#include +#include + +#ifdef RSEQ_SIG +#include +#include +#include +#include +#include +#include +#include + +static int +rseq_thread_registered (void) +{ + return (int32_t) atomic_load_relaxed (&__rseq_abi.cpu_id) >= 0; +} + +static int +do_rseq_main_test (void) +{ + if (!rseq_thread_registered ()) + { + FAIL_RET ("rseq not registered in main thread"); + } + return 0; +} + +static int +sys_rseq (struct rseq *rseq_abi, uint32_t rseq_len, int flags, uint32_t sig) +{ + return syscall (__NR_rseq, rseq_abi, rseq_len, flags, sig); +} + +static int +rseq_available (void) +{ + int rc; + + rc = sys_rseq (NULL, 0, 0, 0); + if (rc != -1) + FAIL_EXIT1 ("Unexpected rseq return value %d", rc); + switch (errno) + { + case ENOSYS: + return 0; + case EINVAL: + return 1; + default: + FAIL_EXIT1 ("Unexpected rseq error %s", strerror (errno)); + } +} + +static int +do_rseq_test (void) +{ + int result = 0; + + if (!rseq_available ()) + { + FAIL_UNSUPPORTED ("kernel does not support rseq, skipping test"); + } + if (do_rseq_main_test ()) + result = 1; + return result; +} +#else +static int +do_rseq_test (void) +{ +#ifndef RSEQ_SIG + FAIL_UNSUPPORTED ("glibc does not define RSEQ_SIG, skipping test"); +#endif + return 0; +} +#endif + +static int +do_test (void) +{ + return do_rseq_test (); +} + +#include