From patchwork Fri Mar 22 01:53:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenz Bauer X-Patchwork-Id: 1060700 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.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=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=quarantine dis=none) header.from=cloudflare.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=cloudflare.com header.i=@cloudflare.com header.b="CxQzIgv/"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44QRXz5VVdz9sRy for ; Fri, 22 Mar 2019 12:54:27 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727599AbfCVBy1 (ORCPT ); Thu, 21 Mar 2019 21:54:27 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:45531 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727596AbfCVBy1 (ORCPT ); Thu, 21 Mar 2019 21:54:27 -0400 Received: by mail-pg1-f193.google.com with SMTP id y3so325694pgk.12 for ; Thu, 21 Mar 2019 18:54:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloudflare.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=FZY4iMerFf3oc3fyXl4BxDRKcJ+uuJ5mc1g/4bPlNws=; b=CxQzIgv/1BV0szdswL32lV97Oe20rEXDU5VsiqxwGvlDGFF4FKb4KsbEfsLARHX+3Q qITlE/52GTmHTw5miTCpzxLebLWOCGtDp2EFQjHs8FyFQkiMBp4K3nem58P+gBwvYMEq u0rIM9gDjVs3x6WaQ+vYeTEWUcJPZGAMNOIT0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=FZY4iMerFf3oc3fyXl4BxDRKcJ+uuJ5mc1g/4bPlNws=; b=gcXUZDKSLzBxHNJqxgQg7cumyO20h4ip2+Cr1D7wR6d/II4o+YbD82DugNdWf2lIxH WbOC0D7QoGaY3fM20aZds3t6DgGjk5AVIAPCgwkTKJFmYNyQkiVa59Zk1bur0UN/KG+Q ad3Fe5j+O5UsZiEbUAxlrU7nojsHdgdnMcUh5W0bzfj6LyUkoZXvHa4MoKdHp0o5C/zL 6h26768TDtCnrccv3Kh3nJe1bLLSo2Nt/GUwa1mbKHus3MrY/3ietS3JirflfvIP5Nmm Zh7aOEAyx96lOcPrrAgrVYykVQmznLZ7EVmMsLZzPXYZcvZnIC2GQlv3r0kyGvZr8DZl +lYA== X-Gm-Message-State: APjAAAV6XxugPuJqDwKDfJASfhwbwn4efQ0ebxOFOzK4RBj+jkSrUy0g AaM5vanZQgMNvOIJ58MJvc5eD6LvqEYNTw== X-Google-Smtp-Source: APXvYqzJbqBWmUZ9WA3da8Hzr8owuV/cfFhx1Ie5ZQzDkJgS6dOF+TROS94nSq6aV5nbC6wq/6K/tg== X-Received: by 2002:a62:7049:: with SMTP id l70mr6607371pfc.78.1553219666394; Thu, 21 Mar 2019 18:54:26 -0700 (PDT) Received: from localhost.localdomain ([157.120.241.186]) by smtp.gmail.com with ESMTPSA id i10sm7161799pgs.26.2019.03.21.18.54.23 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 21 Mar 2019 18:54:25 -0700 (PDT) From: Lorenz Bauer To: ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, bpf@vger.kernel.org Cc: kafai@fb.com, Lorenz Bauer Subject: [PATCH bpf-next v3 1/8] bpf: track references based on is_acquire_func Date: Fri, 22 Mar 2019 09:53:59 +0800 Message-Id: <20190322015406.26453-2-lmb@cloudflare.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190322015406.26453-1-lmb@cloudflare.com> References: <20190319102103.7380-1-lmb@cloudflare.com> <20190322015406.26453-1-lmb@cloudflare.com> MIME-Version: 1.0 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-Id: netdev.vger.kernel.org So far, the verifier only acquires reference tracking state for RET_PTR_TO_SOCKET_OR_NULL. Instead of extending this for every new return type which desires these semantics, acquire reference tracking state iff the called helper is an acquire function. Signed-off-by: Lorenz Bauer --- kernel/bpf/verifier.c | 26 ++++++++++++-------------- 1 file changed, 12 insertions(+), 14 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 86f9cd5d1c4e..868a82ad5597 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3147,19 +3147,7 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn } else if (fn->ret_type == RET_PTR_TO_SOCKET_OR_NULL) { mark_reg_known_zero(env, regs, BPF_REG_0); regs[BPF_REG_0].type = PTR_TO_SOCKET_OR_NULL; - if (is_acquire_function(func_id)) { - int id = acquire_reference_state(env, insn_idx); - - if (id < 0) - return id; - /* For mark_ptr_or_null_reg() */ - regs[BPF_REG_0].id = id; - /* For release_reference() */ - regs[BPF_REG_0].ref_obj_id = id; - } else { - /* For mark_ptr_or_null_reg() */ - regs[BPF_REG_0].id = ++env->id_gen; - } + regs[BPF_REG_0].id = ++env->id_gen; } else if (fn->ret_type == RET_PTR_TO_TCP_SOCK_OR_NULL) { mark_reg_known_zero(env, regs, BPF_REG_0); regs[BPF_REG_0].type = PTR_TO_TCP_SOCK_OR_NULL; @@ -3170,9 +3158,19 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn return -EINVAL; } - if (is_ptr_cast_function(func_id)) + if (is_ptr_cast_function(func_id)) { /* For release_reference() */ regs[BPF_REG_0].ref_obj_id = meta.ref_obj_id; + } else if (is_acquire_function(func_id)) { + int id = acquire_reference_state(env, insn_idx); + + if (id < 0) + return id; + /* For mark_ptr_or_null_reg() */ + regs[BPF_REG_0].id = id; + /* For release_reference() */ + regs[BPF_REG_0].ref_obj_id = id; + } do_refine_retval_range(regs, fn->ret_type, func_id, &meta);