From nobody Mon May 11 04:52:12 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1E03C433EF for ; Thu, 14 Apr 2022 05:08:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239826AbiDNFLQ (ORCPT ); Thu, 14 Apr 2022 01:11:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47266 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229447AbiDNFLM (ORCPT ); Thu, 14 Apr 2022 01:11:12 -0400 Received: from mail-pg1-x531.google.com (mail-pg1-x531.google.com [IPv6:2607:f8b0:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 282933C4B5; Wed, 13 Apr 2022 22:08:49 -0700 (PDT) Received: by mail-pg1-x531.google.com with SMTP id u2so3806239pgq.10; Wed, 13 Apr 2022 22:08:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id; bh=BXdefmByfbS7iadyHNuWA+1dWRCSn9oFrWGYl5Fm5mk=; b=QC4YhFn1wllW1lC8gGSTmQFcF7BKiGku0fd0KEfKjckRUB1fOizADvm++YKwNJFLc6 +p3eYn++B8ekg9AlERZxlEGP4EGWCW45H3Bh0NIKjNlicWv3ADwMzRdciFPgkUxy7TdQ MyvYxZSnGgTqL7PvRoNpEbyabTi2MfWPgu764RWig9VQDiYv19sPLGNZKNOxurugG7YF AFSaTnD3n21Zot+8WlvXif9ut80zGJ6kaZJiHH5Toc+jTNzMkEMZwCaxnQDvT2RVDOtN bxxfEe9q4xMbuhbDRm1KRN3eMUJa2yHoxSJKU84eH5BkDlP232pGpxWaO6+1UgaIeHu1 p2Ew== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=BXdefmByfbS7iadyHNuWA+1dWRCSn9oFrWGYl5Fm5mk=; b=RobqDztKqjR/Yaveg8hY1y92wPrp/ZmXybjLXYXTBk7K+dcFo2lpDI3ETbiD1Kao6J SJF8VHHM1LwGCkKsOx7SDkhc+pEZxgSrVhesm+0IOf0AhLbmjRYyrEN4Vt7t4yabp46c gvCDuCDty2nOJpprbOwa/MrYi89P7dGOnKN0kfeOmK4WrSe/V/HcsqQDkVLGF5iQztCP P03lc7yuTig0A8D3iWk2pUaX3LG08XPKqCi/urJQJ6bNnUrETNM5yffDnHbvh+E6gO4u iJfEeqQ+7lDFYXASqHpVMt0ysgXI3mbWAB/aozHJNVoNt42rINQAmqAze9mxt6MOtx0B ki7A== X-Gm-Message-State: AOAM530fqranKXGHpIpNMInbZ+sj/Cx/OSccga0vwkTkQ/VwMMyG7NJO aM7WvAbQ9OBTKWHlCfeYN7w= X-Google-Smtp-Source: ABdhPJw2MWj6GujCGgHKVad2Vx8MRhaCT+wPaYACtZPvQZoVgZALyIcPZCbAatA+aPcL59Ad7T7eBA== X-Received: by 2002:a63:78f:0:b0:39e:11d0:daa4 with SMTP id 137-20020a63078f000000b0039e11d0daa4mr942690pgh.36.1649912928665; Wed, 13 Apr 2022 22:08:48 -0700 (PDT) Received: from localhost.localdomain ([119.3.119.18]) by smtp.gmail.com with ESMTPSA id b2-20020a056a000a8200b004e1414f0bb1sm763936pfl.135.2022.04.13.22.08.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 13 Apr 2022 22:08:48 -0700 (PDT) From: Xiaomeng Tong To: agross@kernel.org, bjorn.andersson@linaro.org, joro@8bytes.org, will@kernel.org, sricharan@codeaurora.org Cc: linux-arm-msm@vger.kernel.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Xiaomeng Tong , stable@vger.kernel.org Subject: [RESEND][PATCH] iommu: fix an incorrect NULL check on list iterator Date: Thu, 14 Apr 2022 13:08:40 +0800 Message-Id: <20220414050840.5691-1-xiam0nd.tong@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" The bug is here: if (!iommu || iommu->dev->of_node !=3D spec->np) { The list iterator value 'iommu' will *always* be set and non-NULL by list_for_each_entry(), so it is incorrect to assume that the iterator value will be NULL if the list is empty or no element is found (in fact, it will point to a invalid structure object containing HEAD). To fix the bug, run insert_iommu_master(dev, &iommu, spec); unlock and return 0 when found, otherwise unlock and return -ENODEV. Cc: stable@vger.kernel.org Fixes: f78ebca8ff3d6 ("iommu/msm: Add support for generic master bindings") Signed-off-by: Xiaomeng Tong --- drivers/iommu/msm_iommu.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c index 3a38352b603f..1dbb8b0695ec 100644 --- a/drivers/iommu/msm_iommu.c +++ b/drivers/iommu/msm_iommu.c @@ -617,23 +617,17 @@ static int qcom_iommu_of_xlate(struct device *dev, { struct msm_iommu_dev *iommu; unsigned long flags; - int ret =3D 0; =20 spin_lock_irqsave(&msm_iommu_lock, flags); list_for_each_entry(iommu, &qcom_iommu_devices, dev_node) - if (iommu->dev->of_node =3D=3D spec->np) - break; - - if (!iommu || iommu->dev->of_node !=3D spec->np) { - ret =3D -ENODEV; - goto fail; - } - - insert_iommu_master(dev, &iommu, spec); -fail: + if (iommu->dev->of_node =3D=3D spec->np) { + insert_iommu_master(dev, &iommu, spec); + spin_unlock_irqrestore(&msm_iommu_lock, flags); + return 0; + } spin_unlock_irqrestore(&msm_iommu_lock, flags); =20 - return ret; + return -ENODEV; } =20 irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id) --=20 2.17.1