From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5D26FC38A2B for ; Fri, 17 Apr 2020 18:48:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F142207FC for ; Fri, 17 Apr 2020 18:48:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=sifive.com header.i=@sifive.com header.b="m55vm8qp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729241AbgDQSst (ORCPT ); Fri, 17 Apr 2020 14:48:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47410 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1727919AbgDQSss (ORCPT ); Fri, 17 Apr 2020 14:48:48 -0400 Received: from mail-pg1-x541.google.com (mail-pg1-x541.google.com [IPv6:2607:f8b0:4864:20::541]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D5837C061A10 for ; Fri, 17 Apr 2020 11:48:48 -0700 (PDT) Received: by mail-pg1-x541.google.com with SMTP id p8so1526899pgi.5 for ; Fri, 17 Apr 2020 11:48:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sifive.com; s=google; h=from:to:cc:subject:date:message-id; bh=/m8uFUPGMTXPG6uE9UPBDXEGsmlpHvFfRMPeQIRglr0=; b=m55vm8qpsWewOdjKtNV9pAA/o9+H6/LdDotUxWcE6LTAdjTMH4J3LNhBIZ6wWCKmNo 99GRImy6d5PLzuLZIH/aZlDXNr4DtUD48apChLpnvfxnpETe7l3oPQ/WtRQkVvRbdfSu skGOb/Tf+DAYWM4gntE5s80z0Yp0jHTWnqeG1ydjvMReWaJpGPGN3j/d1iPXF1Hn5uan M2t5AhwXcWJNEYNQJATDZ8rLCSC+jlt2B2QpqBzhNwiOer5QagoHIXeHh6Argt7eoU4j kU5xp6C9bqgXqa0hoED9I6CRFHE+bbrN49TWBqh14XXShfG5joisVXURuPXDedM/kDU7 Npqw== 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; bh=/m8uFUPGMTXPG6uE9UPBDXEGsmlpHvFfRMPeQIRglr0=; b=fn99uTxHYRgDBL04gQmIJ1FnnfyvkxhQVdC10hY7kCtFg6XcZe9yT1a39S/eYjmynI KKHgVECCAEpzmOTiKQlJfRzDuPrlwqBgrkVvCR2+rkdNpgG+jJ9oCZfE6BLk0n2Z3VrD f0+NHYw70KKCkvaWSEEiXItU5SAL/9GKd2wlR+n/lQWQtI5F/MYQ8GKNpj80jnIQh91k N9lQEiMaUfSZn1mizFl4/1VIwMl8kDriGAQoVwEYAK7irXkfuGTuydBi0Yp7ou9ty/mV M/I9OMhap86SBNxbncQ1kyJ09X3dI5kOED6pj+Knbm1wC5MCWeKfwxUxapax8WlGSEbk VYSQ== X-Gm-Message-State: AGi0PuZ3gx7qE9eICFeqJkACt2GLh5FE7xCMJ8fJYceQ4d5iQgT1t1fL v2Z6GRCxvz3z1IaDZUVHCRFEYGZn8Hs= X-Google-Smtp-Source: APiQypJVSsNxOrC49Bt1KeprvKNWUF/fOBKhWHYpgHUpDM7iS/wLjotWqC0uiFeh2vhCtRy4gCIUgQ== X-Received: by 2002:aa7:9207:: with SMTP id 7mr4521820pfo.178.1587149327949; Fri, 17 Apr 2020 11:48:47 -0700 (PDT) Received: from nuc7.sifive.com (c-24-5-48-146.hsd1.ca.comcast.net. [24.5.48.146]) by smtp.gmail.com with ESMTPSA id l185sm18924449pfl.104.2020.04.17.11.48.46 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 17 Apr 2020 11:48:46 -0700 (PDT) From: Alan Mikhak X-Google-Original-From: Alan Mikhak < alan.mikhak@sifive.com > To: linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org, linux-pci@vger.kernel.org, maz@kernel.org, tglx@linutronix.de, gustavo.pimentel@synopsys.com, kishon@ti.com, paul.walmsley@sifive.com Cc: Alan Mikhak Subject: [PATCH] genirq/msi: Check null pointer before copying struct msi_msg Date: Fri, 17 Apr 2020 11:48:42 -0700 Message-Id: <1587149322-28104-1-git-send-email-alan.mikhak@sifive.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alan Mikhak Modify __get_cached_msi_msg() to check both pointers for null before copying the contents from the struct msi_msg pointer to the pointer provided by caller. Without this sanity check, __get_cached_msi_msg() crashes when invoked by dw_edma_irq_request() in drivers/dma/dw-edma/dw-edma-core.c running on a Linux-based PCIe endpoint device. MSI interrupt are not received by PCIe endpoint devices. As a result, irq_get_msi_desc() returns null since there are no cached struct msi_msg entry on the endpoint side. Signed-off-by: Alan Mikhak --- kernel/irq/msi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index eb95f6106a1e..f39d42ef0d50 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -58,7 +58,8 @@ void free_msi_entry(struct msi_desc *entry) void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg) { - *msg = entry->msg; + if (entry && msg) + *msg = entry->msg; } void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg) -- 2.7.4