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=-5.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 C806DC43613 for ; Thu, 20 Jun 2019 18:25:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A4A2720665 for ; Thu, 20 Jun 2019 18:25:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561055103; bh=dDIlcOc0mj6TJSxSLEG7JNU0rapaycQ7btP3ssfYTcM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=EhnSSUuuEIlUHyoIKF7j5ojO7EL1fAQaQSujtUVq04GPame2+VMCY/WboS7GFG8vv UVfdD0RdpANzCfp9eoO+aNllikSeQD36IhJbVDq0ZBRAk72AUe2ssQL5Otoxt6nSxZ Q/xZDt9n28lm3NEG1tAUIoi4CbO8BKa6J+dUc1tE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726375AbfFTSHz (ORCPT ); Thu, 20 Jun 2019 14:07:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:34740 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728384AbfFTSHw (ORCPT ); Thu, 20 Jun 2019 14:07:52 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1B6372084E; Thu, 20 Jun 2019 18:07:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561054071; bh=dDIlcOc0mj6TJSxSLEG7JNU0rapaycQ7btP3ssfYTcM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1CwL8mGOLr4J4X1ID1a3sLTcOXMZaH9mfHNzvLp4yrQi8FqFqjDpzsTH8Wdjtc/fb hdlwT6lU/1l9KqnsO1WhE/4Zx8/ZhSdFzri1o9H5D6aV4H9GMxtp0eZghSMeYrvagU vhvCmesDY7+rgVJyi/zx2OpzhqIDzr8p7Jjt0Yzg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Adrian Hunter , Alexander Shishkin , Andrei Vagin , David Ahern , Jiri Olsa , Namhyung Kim , Peter Zijlstra , Vasily Averin , Wang Nan , Arnaldo Carvalho de Melo , Tommi Rantala Subject: [PATCH 4.14 01/45] perf machine: Guard against NULL in machine__exit() Date: Thu, 20 Jun 2019 19:57:03 +0200 Message-Id: <20190620174329.129654050@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190620174328.608036501@linuxfoundation.org> References: <20190620174328.608036501@linuxfoundation.org> User-Agent: quilt/0.66 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Arnaldo Carvalho de Melo commit 4a2233b194c77ae1ea8304cb7c00b551de4313f0 upstream. A recent fix for 'perf trace' introduced a bug where machine__exit(trace->host) could be called while trace->host was still NULL, so make this more robust by guarding against NULL, just like free() does. The problem happens, for instance, when !root users try to run 'perf trace': [acme@jouet linux]$ trace Error: No permissions to read /sys/kernel/debug/tracing/events/raw_syscalls/sys_(enter|exit) Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug/tracing' perf: Segmentation fault Obtained 7 stack frames. [0x4f1b2e] /lib64/libc.so.6(+0x3671f) [0x7f43a1dd971f] [0x4f3fec] [0x47468b] [0x42a2db] /lib64/libc.so.6(__libc_start_main+0xe9) [0x7f43a1dc3509] [0x42a6c9] Segmentation fault (core dumped) [acme@jouet linux]$ Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andrei Vagin Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Vasily Averin Cc: Wang Nan Fixes: 33974a414ce2 ("perf trace: Call machine__exit() at exit") Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Tommi Rantala Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/machine.c | 3 +++ 1 file changed, 3 insertions(+) --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -156,6 +156,9 @@ void machine__delete_threads(struct mach void machine__exit(struct machine *machine) { + if (machine == NULL) + return; + machine__destroy_kernel_maps(machine); map_groups__exit(&machine->kmaps); dsos__exit(&machine->dsos);