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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 9A36AC433FF for ; Tue, 6 Aug 2019 21:35:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 649A721874 for ; Tue, 6 Aug 2019 21:35:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565127346; bh=uaoAP0RYgmLFAgqlfAfjdWejslREn9k7x9lGtVwS8zk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=urYJoRoqGhV6NbrSdnfB3MIH6AfTl/ikC9VEP5dTlzyMia6xglXlhdl22ZDoE33B9 jnf/3JeG9x/4AX2ngOtv27C3xy8gSCvql+I380CYILX4WcGnebjwKfJPseEKq3ryT+ ceSEkc4r8jbutqIvx+RVTSYI0i+AgsBNeVKOjYGM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728676AbfHFVfp (ORCPT ); Tue, 6 Aug 2019 17:35:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:53406 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728582AbfHFVfj (ORCPT ); Tue, 6 Aug 2019 17:35:39 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BB9B12186A; Tue, 6 Aug 2019 21:35:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565127338; bh=uaoAP0RYgmLFAgqlfAfjdWejslREn9k7x9lGtVwS8zk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sXrKoObfQGMZ+HrG5isq4fKIAC8T89SbW5ZS5xOyaj+LAlqcQGCJcwDKn68OGfpFc kCKpWUqNPuFLQfye/7QXtaOXyi32dij1IdxiB6aZ0xbvJlDrTrt3KJn5+13BFiDHbN lSes4453FB9k6WhDMFth1dNefRm6DPNsE2PCR2vk= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Vince Weaver , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Peter Zijlstra , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH AUTOSEL 4.19 08/32] perf header: Fix divide by zero error if f_header.attr_size==0 Date: Tue, 6 Aug 2019 17:34:56 -0400 Message-Id: <20190806213522.19859-8-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190806213522.19859-1-sashal@kernel.org> References: <20190806213522.19859-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vince Weaver [ Upstream commit 7622236ceb167aa3857395f9bdaf871442aa467e ] So I have been having lots of trouble with hand-crafted perf.data files causing segfaults and the like, so I have started fuzzing the perf tool. First issue found: If f_header.attr_size is 0 in the perf.data file, then perf will crash with a divide-by-zero error. Committer note: Added a pr_err() to tell the user why the command failed. Signed-off-by: Vince Weaver Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/alpine.DEB.2.21.1907231100440.14532@macbook-air Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/util/header.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c index 7f2e3b1c746c9..94278f914cdca 100644 --- a/tools/perf/util/header.c +++ b/tools/perf/util/header.c @@ -3285,6 +3285,13 @@ int perf_session__read_header(struct perf_session *session) data->file.path); } + if (f_header.attr_size == 0) { + pr_err("ERROR: The %s file's attr size field is 0 which is unexpected.\n" + "Was the 'perf record' command properly terminated?\n", + data->file.path); + return -EINVAL; + } + nr_attrs = f_header.attrs.size / f_header.attr_size; lseek(fd, f_header.attrs.offset, SEEK_SET); -- 2.20.1