From patchwork Mon Jul 13 17:55:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Saheed O. Bolarinwa" X-Patchwork-Id: 1328273 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4B593p3KLLz9sQt for ; Tue, 14 Jul 2020 03:04:22 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=QThq7T/N; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4B593p1kr3zDqWc for ; Tue, 14 Jul 2020 03:04:22 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gmail.com (client-ip=2a00:1450:4864:20::543; helo=mail-ed1-x543.google.com; envelope-from=refactormyself@gmail.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=QThq7T/N; dkim-atps=neutral Received: from mail-ed1-x543.google.com (mail-ed1-x543.google.com [IPv6:2a00:1450:4864:20::543]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4B58sN3Cj9zDqPS for ; Tue, 14 Jul 2020 02:55:19 +1000 (AEST) Received: by mail-ed1-x543.google.com with SMTP id bm28so12302820edb.2 for ; Mon, 13 Jul 2020 09:55:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=Vg5seoeyahxUOJ1a2of2OSXbNHc8+N6IhRiLy4XR8Ps=; b=QThq7T/NhE4spupA48w9flKBPIUZMsJ+uy1wChEjqmd9cLUhJNeozt9BNv1EslTKul 9FzUYVh1psv92TVnmY05kmXxx7YOjo4zsDzZUATn9e4zIhaa/IU/l64wBzjWvrwDbAdT yMVtRLi35HfG89vS3VWmX51PcL78Kumuk1a4Y+mb2X5zojZOcrMRGnHmOxMBpNMDphyn WM6skKGt7eauq9PMF4fMY/WlqUw991iJ1Ytz1rk4085GlJxA7KXFCo39uIxgjXQ9fuJN 3z5H1aRueRaa67gizAbiKT/8yQ6CvE9P5qTMm1ibl2NWyp9eZcuTPcv+4+0VHPs7z+dy 9v1Q== 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; bh=Vg5seoeyahxUOJ1a2of2OSXbNHc8+N6IhRiLy4XR8Ps=; b=iV5vqHkh+3JZsw+t0YCjdKBHSLbBCPJffK03A7mk6MwNGSXqBLx9vtbTct9icjq6ff OdKTEc3HOW944YqPkx5cPYsvAh/p1sqjoC7gh+K0T/j+KuFHZfzSDNnM4kBmNS8XDL7C zoMwJiilhspYNlMPlZAkSPCJCTiIAwV5zOK52oOZS8wESfq/cbyWuKovZ0Qi9E7clCet HILgz5w/8H5koqIZlif3xDuMGqAyPtqSkbH+D7qKiU4zFj0dNHCHNI0fUKJLa1U5T1/y ZuPkHQ6u+vNEnTJMZhYRtFFhoLT9LWuxiJSFg6hitRXIrdmNAgjV8pWGRRfhCUtoMbWN tcvA== X-Gm-Message-State: AOAM532GQb+y0Pqhc2qcvr1MIHrQCe8bWOyeThYncKdm10hLpOVKJZbk bYlUEYfeJkfQ/L5ZsrC2C7Y= X-Google-Smtp-Source: ABdhPJwiuJGYBhFGQzVTlihXWfzHv/j6TtpsUC2ukWbQvIDZs82x6qtdrhI4g0KTxQkpdk5UBwbo4Q== X-Received: by 2002:aa7:d58c:: with SMTP id r12mr365600edq.160.1594659316271; Mon, 13 Jul 2020 09:55:16 -0700 (PDT) Received: from net.saheed (54007186.dsl.pool.telekom.hu. [84.0.113.134]) by smtp.gmail.com with ESMTPSA id w3sm11838938edq.65.2020.07.13.09.55.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Jul 2020 09:55:15 -0700 (PDT) From: "Saheed O. Bolarinwa" To: skhan@linuxfoundation.org, linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel-mentees@lists.linuxfoundation.org, linux-kernel@vger.kernel.org Subject: [PATCH 12/14 v3] PCI/AER: Check the return value of pcie_capability_read_*() Date: Mon, 13 Jul 2020 19:55:29 +0200 Message-Id: <20200713175529.29715-5-refactormyself@gmail.com> X-Mailer: git-send-email 2.18.2 In-Reply-To: <20200713175529.29715-1-refactormyself@gmail.com> References: <20200713175529.29715-1-refactormyself@gmail.com> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Bolarinwa Olayemi Saheed Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Bolarinwa Olayemi Saheed On failure pcie_capability_read_dword() sets it's last parameter, val to 0. However, with Patch 14/14, it is possible that val is set to ~0 on failure. This would introduce a bug because (x & x) == (~0 & x). This bug can be avoided if the return value of pcie_capability_read_word is checked to confirm success. Check the return value of pcie_capability_read_word() to ensure success. Suggested-by: Bjorn Helgaas Signed-off-by: Bolarinwa Olayemi Saheed --- drivers/pci/pcie/aer.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c index 3acf56683915..f4beb47c622c 100644 --- a/drivers/pci/pcie/aer.c +++ b/drivers/pci/pcie/aer.c @@ -800,6 +800,7 @@ static bool is_error_source(struct pci_dev *dev, struct aer_err_info *e_info) int aer = dev->aer_cap; u32 status, mask; u16 reg16; + int ret; /* * When bus id is equal to 0, it might be a bad id @@ -828,8 +829,8 @@ static bool is_error_source(struct pci_dev *dev, struct aer_err_info *e_info) return false; /* Check if AER is enabled */ - pcie_capability_read_word(dev, PCI_EXP_DEVCTL, ®16); - if (!(reg16 & PCI_EXP_AER_FLAGS)) + ret = pcie_capability_read_word(dev, PCI_EXP_DEVCTL, ®16); + if (ret || !(reg16 & PCI_EXP_AER_FLAGS)) return false; if (!aer)