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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6469CC6FD1A for ; Tue, 7 Mar 2023 17:35:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231426AbjCGRfI (ORCPT ); Tue, 7 Mar 2023 12:35:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33198 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231776AbjCGRej (ORCPT ); Tue, 7 Mar 2023 12:34:39 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 37CCFA227A for ; Tue, 7 Mar 2023 09:30:40 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BB7E961519 for ; Tue, 7 Mar 2023 17:30:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7FB0FC433D2; Tue, 7 Mar 2023 17:30:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678210239; bh=wEqXAZceX8Upi4lDtHeLpJ+sCtea/q0T/GBQUiH/v54=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R5eN8ml5C4mjqLQ82q65rTLmE+KiGXCuQIGMjSo9pw0XajUFul/ChojATQxH40ivA k/XgCmESEvzqib091sWRsnL+pZpaRHMkWF/QEZOet/z98o3y0hGKdJlPInXzTkGlnr pbz2daBuLUaQqk6TCcqvO0dKu8PVkkcKlFIpY3AE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yang Jihong , Namhyung Kim , Alexander Shishkin , Ingo Molnar , Jiri Olsa , Jiwei Sun , Mark Rutland , Peter Zijlstra , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH 6.2 0477/1001] perf record: Fix segfault with --overwrite and --max-size Date: Tue, 7 Mar 2023 17:54:09 +0100 Message-Id: <20230307170042.104740959@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230307170022.094103862@linuxfoundation.org> References: <20230307170022.094103862@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Yang Jihong [ Upstream commit 91621be65d6812cd74b2ea09573ff9ee0cbf5666 ] When --overwrite and --max-size options of perf record are used together, a segmentation fault occurs. The following is an example: # perf record -e sched:sched* --overwrite --max-size 1K -a -- sleep 1 [ perf record: Woken up 1 times to write data ] perf: Segmentation fault Obtained 12 stack frames. ./perf/perf(+0x197673) [0x55f99710b673] /lib/x86_64-linux-gnu/libc.so.6(+0x3ef0f) [0x7fa45f3cff0f] ./perf/perf(+0x8eb40) [0x55f997002b40] ./perf/perf(+0x1f6882) [0x55f99716a882] ./perf/perf(+0x794c2) [0x55f996fed4c2] ./perf/perf(+0x7b7c7) [0x55f996fef7c7] ./perf/perf(+0x9074b) [0x55f99700474b] ./perf/perf(+0x12e23c) [0x55f9970a223c] ./perf/perf(+0x12e54a) [0x55f9970a254a] ./perf/perf(+0x7db60) [0x55f996ff1b60] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe6) [0x7fa45f3b2c86] ./perf/perf(+0x7dfe9) [0x55f996ff1fe9] Segmentation fault (core dumped) backtrace of the core file is as follows: (gdb) bt #0 record__bytes_written (rec=0x55f99755a200 ) at builtin-record.c:234 #1 record__output_max_size_exceeded (rec=0x55f99755a200 ) at builtin-record.c:242 #2 record__write (map=0x0, size=12816, bf=0x55f9978da2e0, rec=0x55f99755a200 ) at builtin-record.c:263 #3 process_synthesized_event (tool=tool@entry=0x55f99755a200 , event=event@entry=0x55f9978da2e0, sample=sample@entry=0x0, machine=machine@entry=0x55f997893658) at builtin-record.c:618 #4 0x000055f99716a883 in __perf_event__synthesize_id_index (tool=tool@entry=0x55f99755a200 , process=process@entry=0x55f997002aa0 , evlist=0x55f9978928b0, machine=machine@entry=0x55f997893658, from=from@entry=0) at util/synthetic-events.c:1895 #5 0x000055f99716a91f in perf_event__synthesize_id_index (tool=tool@entry=0x55f99755a200 , process=process@entry=0x55f997002aa0 , evlist=, machine=machine@entry=0x55f997893658) at util/synthetic-events.c:1905 #6 0x000055f996fed4c3 in record__synthesize (tail=tail@entry=true, rec=0x55f99755a200 ) at builtin-record.c:1997 #7 0x000055f996fef7c8 in __cmd_record (argc=argc@entry=2, argv=argv@entry=0x7ffc67551260, rec=0x55f99755a200 ) at builtin-record.c:2802 #8 0x000055f99700474c in cmd_record (argc=, argv=0x7ffc67551260) at builtin-record.c:4258 #9 0x000055f9970a223d in run_builtin (p=0x55f997564d88 , argc=10, argv=0x7ffc67551260) at perf.c:330 #10 0x000055f9970a254b in handle_internal_command (argc=10, argv=0x7ffc67551260) at perf.c:384 #11 0x000055f996ff1b61 in run_argv (argcp=, argv=) at perf.c:428 #12 main (argc=, argv=0x7ffc67551260) at perf.c:562 The reason is that record__bytes_written accesses the freed memory rec->thread_data, The process is as follows: __cmd_record -> record__free_thread_data -> zfree(&rec->thread_data) // free rec->thread_data -> record__synthesize -> perf_event__synthesize_id_index -> process_synthesized_event -> record__write -> record__bytes_written // access rec->thread_data We add a member variable "thread_bytes_written" in the struct "record" to save the data size written by the threads. Fixes: 6d57581659f72299 ("perf record: Add support for limit perf output file size") Signed-off-by: Yang Jihong Acked-by: Namhyung Kim Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Jiri Olsa Cc: Jiwei Sun Cc: Mark Rutland Cc: Peter Zijlstra Link: https://lore.kernel.org/r/CAM9d7ci_TRrqBQVQNW8=GwakUr7SsZpYxaaty-S4bxF8zJWyqw@mail.gmail.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/builtin-record.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 29dcd454b8e21..8374117e66f6e 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -154,6 +154,7 @@ struct record { struct perf_tool tool; struct record_opts opts; u64 bytes_written; + u64 thread_bytes_written; struct perf_data data; struct auxtrace_record *itr; struct evlist *evlist; @@ -226,14 +227,7 @@ static bool switch_output_time(struct record *rec) static u64 record__bytes_written(struct record *rec) { - int t; - u64 bytes_written = rec->bytes_written; - struct record_thread *thread_data = rec->thread_data; - - for (t = 0; t < rec->nr_threads; t++) - bytes_written += thread_data[t].bytes_written; - - return bytes_written; + return rec->bytes_written + rec->thread_bytes_written; } static bool record__output_max_size_exceeded(struct record *rec) @@ -255,10 +249,12 @@ static int record__write(struct record *rec, struct mmap *map __maybe_unused, return -1; } - if (map && map->file) + if (map && map->file) { thread->bytes_written += size; - else + rec->thread_bytes_written += size; + } else { rec->bytes_written += size; + } if (record__output_max_size_exceeded(rec) && !done) { fprintf(stderr, "[ perf record: perf size limit reached (%" PRIu64 " KB)," -- 2.39.2