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=-9.6 required=3.0 tests=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 34615C433E0 for ; Thu, 18 Jun 2020 00:39:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 08EDC2168B for ; Thu, 18 Jun 2020 00:39:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Cy+PtbEF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726879AbgFRAj3 (ORCPT ); Wed, 17 Jun 2020 20:39:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726833AbgFRAj3 (ORCPT ); Wed, 17 Jun 2020 20:39:29 -0400 Received: from mail-qk1-x742.google.com (mail-qk1-x742.google.com [IPv6:2607:f8b0:4864:20::742]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA8AEC06174E for ; Wed, 17 Jun 2020 17:39:28 -0700 (PDT) Received: by mail-qk1-x742.google.com with SMTP id q2so4009274qkb.2 for ; Wed, 17 Jun 2020 17:39:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:subject:date:message-id; bh=2rTi7sVYxh2vc2bTkTkIYUM2u0ppPplMS03UqDSUVng=; b=Cy+PtbEF74jCpRkwlJPtIZiv1YjMuA9ctLDf2D6GRsI5hGPGgutVZxTMgGSGsehvvE dtqOH28IEtBqoyIb/o0NDDH9loN8e6EfxKuQsbVh1Sv3b0nbVId+McCUno9PDJyb/CJF UhwYdSxpYOJwMDkx6jo2IJFfj7te/4lfmPN21+ZGVwNRTn3Du292aD+5rYEBnDfcBtlM euIaDf/J2aLKufk5ogY4w8W5a40upGww7+hGazur6S4snuxXHsXh4SrV2i4XnfeTWsI4 6tD1y1xDCut6nOJLL0rxwIe2MTfEK+5H9yq7R95pgEC4+cjFJ4LOknXc33UfkbzLVr6C +DEA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id; bh=2rTi7sVYxh2vc2bTkTkIYUM2u0ppPplMS03UqDSUVng=; b=d0D3d85zOyXZiK/6WV9K+ZGrAbNDcxhiYtFqOPel1vmHEdaj8f6NCZowrvmsewORoU TXh+KQWSqpL6N3mTYwcsOxbQlu0DngJGsb7bhfmmo/0bU5OoWFgatfcvuEusYfROG3rf PuLWg17KmXhqE6FW3ac9kLfDuycXFZWhOQBsx5+JoeBZFhXo3riSJesEPJk8/2HEE4a7 As/TGO64a1H3+siW6//ma/SwvYpuF/Z5Q8Ixv2RG9PKwbEAA7mK1RECzv9aMjWIyUEqK TW1U3r5C4tzvNuOmN43b2qDhMo8ADWVShuonILk7GoS5Uo6ZZtgPS+igPdKQCqIEaqyY Iukg== X-Gm-Message-State: AOAM530OeF5tEm9Hgr1xiBpPd5GJHkNLnMlK4EnaVBBqsiiDtpVpvuDz jnVjc7YIev4h/za3VO0VkIs= X-Google-Smtp-Source: ABdhPJxdV0ykrUh5oqjTY+50oYqRlJtDYcr0Bx93ANiw5+XULviU+C75bakCWcmACjAwiJMzUY/34g== X-Received: by 2002:a05:620a:23a:: with SMTP id u26mr1311929qkm.443.1592440767971; Wed, 17 Jun 2020 17:39:27 -0700 (PDT) Received: from linux.home ([2604:2000:1344:41d:9c3:b47c:c995:4853]) by smtp.googlemail.com with ESMTPSA id p13sm1618060qtk.24.2020.06.17.17.39.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Jun 2020 17:39:27 -0700 (PDT) From: Gaurav Singh To: gaurav1086@gmail.com, Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Tommi Rantala , Thomas Gleixner , linux-kernel@vger.kernel.org (open list:PERFORMANCE EVENTS SUBSYSTEM) Subject: [PATCH] [perf] Fix null pointer deference in nest_epollfd Date: Wed, 17 Jun 2020 20:38:49 -0400 Message-Id: <20200618003916.26644-1-gaurav1086@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a NULL check for worker before dereferencing. Signed-off-by: Gaurav Singh --- tools/perf/bench/epoll-wait.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/tools/perf/bench/epoll-wait.c b/tools/perf/bench/epoll-wait.c index 75dca9773186..42983eb7f82e 100644 --- a/tools/perf/bench/epoll-wait.c +++ b/tools/perf/bench/epoll-wait.c @@ -239,6 +239,9 @@ static void *workerfn(void *arg) static void nest_epollfd(struct worker *w) { + if (!w) + return; + unsigned int i; struct epoll_event ev; int efd = multiq ? w->epollfd : epollfd; -- 2.17.1