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=-12.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 3FC88C4363A for ; Thu, 29 Oct 2020 15:24:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D5D8020759 for ; Thu, 29 Oct 2020 15:24:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="M1sgjLk+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728096AbgJ2PYY (ORCPT ); Thu, 29 Oct 2020 11:24:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727290AbgJ2PYY (ORCPT ); Thu, 29 Oct 2020 11:24:24 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1F9CC0613D5 for ; Thu, 29 Oct 2020 08:24:23 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id 133so2586133pfx.11 for ; Thu, 29 Oct 2020 08:24:23 -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; bh=zz1neG8HMbgvToMzk6oeXFbZ40cR4GHHMQiU0aR3A0M=; b=M1sgjLk+7cF8upAnv9lvL1TawADDInr7ihJzyQomg1453FnhLNCow9ta2dRDS4TvUi mXPZ7uoBawBDCACv36E4RPhNwaTARPt/XPW1PWW6aj2dCWEbkRJg0tKoO2M9ouKn+R7M my92xK0MK+5dcVkhNvu/cu2KMabnB1vv9npVy+D4837RZKZw2BBVHSblRmU0fsz2Vgo9 oPfGbfn7R6e3CSXpVEWFL989yvxjv0NtOsTAldKGP5KdpGVVeuOTdT1mzVbE3afvKiYj mUG8zxfB2LZirUcD3r6tL++0omXNMwS5Oz/m4GWTCWBoEtP8bwLpdNNCi5+1KbHwgb6O pk8A== 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=zz1neG8HMbgvToMzk6oeXFbZ40cR4GHHMQiU0aR3A0M=; b=XDqQMH44t3Kdt4qaVzwaxX3IQaloD+h+MZUtUNmFrcLsnvJ3hqJLdDfkxBgjXtX3dT IJn4TnvFIkOMTrvQPnnxc6zsUyMiQjLdvLjpbE/Gim8Kup2qGvvZYL+2ocw37WxNEcVu qig/NS0YaG2OZJs1b7wgfdpmrMf1m8JxYwfERImpFJXmGGwhbx3WoKiSuWuBxRoL/6Qs 1NuNoizGRK9N/Xc8ng3oyXG1GkgVqUafw9wKzylvNZn5cmD/7R0tObXkkYTIs7XUorco 9tfpKh3cs8gBPXpwM7OYXNnhkseIPtRwCeT6xj7vTWdOi51Lk7QLq/JUCIpRshVvhDn0 7xCg== X-Gm-Message-State: AOAM5324uyysM3lenRYSb5/2Wqpv/zVbWpOtOPC6olnz+crVDL1NKTUZ pvt+wTx9bdwcmnTBnfA9r5Xh9H66z2Y= X-Google-Smtp-Source: ABdhPJzm73yplZ1kaQ5ol8UmDkRTXHndDZ1Rdq/JCaQJNfPUJLZZddfB5c8j7qjMQDn1CqhblROczw== X-Received: by 2002:a62:1603:0:b029:160:98fc:ad23 with SMTP id 3-20020a6216030000b029016098fcad23mr4984589pfw.47.1603985063589; Thu, 29 Oct 2020 08:24:23 -0700 (PDT) Received: from localhost (42-3-19-186.static.netvigator.com. [42.3.19.186]) by smtp.gmail.com with ESMTPSA id h10sm2919356pgj.69.2020.10.29.08.24.22 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Thu, 29 Oct 2020 08:24:23 -0700 (PDT) From: Qiujun Huang To: rostedt@goodmis.org, mingo@redhat.com, linux-kernel@vger.kernel.org Cc: Qiujun Huang Subject: [PATCH] tracing: Fix in out of bounds write in get_trace_buf Date: Thu, 29 Oct 2020 23:24:04 +0800 Message-Id: <20201029152404.3534-1-hqjagain@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The boundary condition should be 3 as we access buffer[buffer->nesting][0]. Fixes: e2ace001176dc ("tracing: Choose static tp_printk buffer by explicit nesting count") Signed-off-by: Qiujun Huang --- kernel/trace/trace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 528971714fc6..196a4b7de48a 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3125,7 +3125,7 @@ static char *get_trace_buf(void) { struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer); - if (!buffer || buffer->nesting >= 4) + if (!buffer || buffer->nesting >= 3) return NULL; buffer->nesting++; -- 2.17.1