From patchwork Mon Mar 18 17:17:37 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 1057967 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.b="YkzThGw7"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44NNG66Sw9z9s6w for ; Tue, 19 Mar 2019 04:19:26 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727238AbfCRRT0 (ORCPT ); Mon, 18 Mar 2019 13:19:26 -0400 Received: from mail-qk1-f201.google.com ([209.85.222.201]:38498 "EHLO mail-qk1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727860AbfCRRSF (ORCPT ); Mon, 18 Mar 2019 13:18:05 -0400 Received: by mail-qk1-f201.google.com with SMTP id c67so3886881qkg.5 for ; Mon, 18 Mar 2019 10:18:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=LfpjTjIWpAUqgBuBr+ROlRDq3TWjVWHbA3wqyLv7Gqg=; b=YkzThGw7U5bxwuGivZfG7gXjy3sbFeGI9LQQNwpjKesMWYXA6dWvmlyTVIDVds3jdT 99Hv46CfyNGepDjQmBrGdjnE8DmIFRJxBJqNXjHLIWC7+99xjXgyacIB4V4zSxrfGRS1 gCdVGS/MQBILBUagjA0XfHFo8FDflJm4SJEr94PsmlNdR79rNuZTcqAgPDOmgM2h8uU1 X27jM72pTPp4w4jfVrzQIbmq9wd3O59csXywpy8yafGddFfq57LOwhbAfJSUMg2BvGCJ ay4PGD3jH0Ph4L+WAj6gW2ezv9U1Ktw+Hx+TJhzvpdvgFTaZaxSZHrZdwWAc4E0uG5zJ mTGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=LfpjTjIWpAUqgBuBr+ROlRDq3TWjVWHbA3wqyLv7Gqg=; b=MS6C3hBmI4Gy4nd50cugonNzG5Cu32H986LrOokWKqG1A2t6wsdNYgCSlc4qrGWX17 brxMsxMxT7lUeL0nRu4i/J+vPF5Ui6eM+LUnK6jyAEPtQoyLufA39lGqn/XcikNOblMN AS1ZE9MWHEm1dv91mIScXdGq4PLIaNmFDOTCiisDvhKt1bLLew44J07/gHK2DlIjHzkZ m5wO3WrmMtS2SiEr1+ah/U4JjzJwbpfhEM7rtThQbzcsiZbLyT2U4tJScGxBNodBg6L8 BtrvdG/gnvl2hKiOnQHQB/gyrGg5H5V83WKbry4V08/UROjnEi4oh/bBFpbbfjMpOHpP kL8g== X-Gm-Message-State: APjAAAWNrkGfJs7MChYBR7Dw4iYOQb8Tm16s6XaF2hSrj4DXCKQNlb5T r6R1MfSt28RdDSykTMZy/qR6DBLXx+mBpnDA X-Google-Smtp-Source: APXvYqwvaFpE6Rrk389WuFNgjhFYIoDJPXDJycXik4soUJpzaOpECOFFeWGr/7DmdYgwI9v4deSBDrsPhVpuummk X-Received: by 2002:aed:3a42:: with SMTP id n60mr10517091qte.62.1552929484433; Mon, 18 Mar 2019 10:18:04 -0700 (PDT) Date: Mon, 18 Mar 2019 18:17:37 +0100 In-Reply-To: Message-Id: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.21.0.225.g810b269d1ac-goog Subject: [PATCH v12 05/13] mm, arm64: untag user pointers in mm/gup.c From: Andrey Konovalov To: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , Eric Dumazet , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy , Andrey Konovalov Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch is a part of a series that extends arm64 kernel ABI to allow to pass tagged user pointers (with the top byte set to something else other than 0x00) as syscall arguments. mm/gup.c provides a kernel interface that accepts user addresses and manipulates user pages directly (for example get_user_pages, that is used by the futex syscall). Since a user can provided tagged addresses, we need to handle this case. Add untagging to gup.c functions that use user addresses for vma lookups. Signed-off-by: Andrey Konovalov --- mm/gup.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/mm/gup.c b/mm/gup.c index f84e22685aaa..3192741e0b3a 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -686,6 +686,8 @@ static long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, if (!nr_pages) return 0; + start = untagged_addr(start); + VM_BUG_ON(!!pages != !!(gup_flags & FOLL_GET)); /* @@ -848,6 +850,8 @@ int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm, struct vm_area_struct *vma; vm_fault_t ret, major = 0; + address = untagged_addr(address); + if (unlocked) fault_flags |= FAULT_FLAG_ALLOW_RETRY;