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=-11.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 CD61EC432C0 for ; Sat, 23 Nov 2019 08:15:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A30F420720 for ; Sat, 23 Nov 2019 08:15:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727194AbfKWIPe (ORCPT ); Sat, 23 Nov 2019 03:15:34 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:36344 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727117AbfKWIPX (ORCPT ); Sat, 23 Nov 2019 03:15:23 -0500 Received: from [5.158.153.53] (helo=tip-bot2.lab.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1iYQZV-0002bt-Nm; Sat, 23 Nov 2019 09:15:13 +0100 Received: from [127.0.1.1] (localhost [IPv6:::1]) by tip-bot2.lab.linutronix.de (Postfix) with ESMTP id C873A1C1ACC; Sat, 23 Nov 2019 09:15:02 +0100 (CET) Date: Sat, 23 Nov 2019 08:15:02 -0000 From: "tip-bot2 for Alexey Budankov" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: perf/core] perf session: Fix decompression of PERF_RECORD_COMPRESSED records Cc: Jiri Olsa , Alexey Budankov , Alexander Shishkin , Andi Kleen , Namhyung Kim , Peter Zijlstra , Arnaldo Carvalho de Melo , x86 , LKML In-Reply-To: References: MIME-Version: 1.0 Message-ID: <157449690272.21853.2015069761475695078.tip-bot2@tip-bot2> X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the perf/core branch of tip: Commit-ID: bb1835a3b86c73aa534ef6430ad40223728dfbc0 Gitweb: https://git.kernel.org/tip/bb1835a3b86c73aa534ef6430ad40223728dfbc0 Author: Alexey Budankov AuthorDate: Mon, 18 Nov 2019 17:21:03 +03:00 Committer: Arnaldo Carvalho de Melo CommitterDate: Tue, 19 Nov 2019 19:31:55 -03:00 perf session: Fix decompression of PERF_RECORD_COMPRESSED records Avoid termination of trace loading in case the last record in the decompressed buffer partly resides in the following mmaped PERF_RECORD_COMPRESSED record. In this case NULL value returned by fetch_mmaped_event() means to proceed to the next mmaped record then decompress it and load compressed events. The issue can be reproduced like this: $ perf record -z -- some_long_running_workload $ perf report --stdio -vv decomp (B): 44519 to 163000 decomp (B): 48119 to 174800 decomp (B): 65527 to 131072 fetch_mmaped_event: head=0x1ffe0 event->header_size=0x28, mmap_size=0x20000: fuzzed perf.data? Error: failed to process sample ... Testing: 71: Zstd perf.data compression/decompression : Ok $ tools/perf/perf report -vv --stdio decomp (B): 59593 to 262160 decomp (B): 4438 to 16512 decomp (B): 285 to 880 Looking at the vmlinux_path (8 entries long) Using vmlinux for symbols decomp (B): 57474 to 261248 prefetch_event: head=0x3fc78 event->header_size=0x28, mmap_size=0x3fc80: fuzzed or compressed perf.data? decomp (B): 25 to 32 decomp (B): 52 to 120 ... Fixes: 57fc032ad643 ("perf session: Avoid infinite loop when seeing invalid header.size") Link: https://marc.info/?l=linux-kernel&m=156580812427554&w=2 Co-developed-by: Jiri Olsa Acked-by: Jiri Olsa Signed-off-by: Alexey Budankov Cc: Alexander Shishkin Cc: Andi Kleen Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/cf782c34-f3f8-2f9f-d6ab-145cee0d5322@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/session.c | 44 +++++++++++++++++++++++--------------- 1 file changed, 27 insertions(+), 17 deletions(-) diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index f07b8ec..8454a65 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -1958,8 +1958,8 @@ out_err: } static union perf_event * -fetch_mmaped_event(struct perf_session *session, - u64 head, size_t mmap_size, char *buf) +prefetch_event(char *buf, u64 head, size_t mmap_size, + bool needs_swap, union perf_event *error) { union perf_event *event; @@ -1971,20 +1971,32 @@ fetch_mmaped_event(struct perf_session *session, return NULL; event = (union perf_event *)(buf + head); + if (needs_swap) + perf_event_header__bswap(&event->header); - if (session->header.needs_swap) + if (head + event->header.size <= mmap_size) + return event; + + /* We're not fetching the event so swap back again */ + if (needs_swap) perf_event_header__bswap(&event->header); - if (head + event->header.size > mmap_size) { - /* We're not fetching the event so swap back again */ - if (session->header.needs_swap) - perf_event_header__bswap(&event->header); - pr_debug("%s: head=%#" PRIx64 " event->header_size=%#x, mmap_size=%#zx: fuzzed perf.data?\n", - __func__, head, event->header.size, mmap_size); - return ERR_PTR(-EINVAL); - } + pr_debug("%s: head=%#" PRIx64 " event->header_size=%#x, mmap_size=%#zx:" + " fuzzed or compressed perf.data?\n",__func__, head, event->header.size, mmap_size); - return event; + return error; +} + +static union perf_event * +fetch_mmaped_event(u64 head, size_t mmap_size, char *buf, bool needs_swap) +{ + return prefetch_event(buf, head, mmap_size, needs_swap, ERR_PTR(-EINVAL)); +} + +static union perf_event * +fetch_decomp_event(u64 head, size_t mmap_size, char *buf, bool needs_swap) +{ + return prefetch_event(buf, head, mmap_size, needs_swap, NULL); } static int __perf_session__process_decomp_events(struct perf_session *session) @@ -1997,10 +2009,8 @@ static int __perf_session__process_decomp_events(struct perf_session *session) return 0; while (decomp->head < decomp->size && !session_done()) { - union perf_event *event = fetch_mmaped_event(session, decomp->head, decomp->size, decomp->data); - - if (IS_ERR(event)) - return PTR_ERR(event); + union perf_event *event = fetch_decomp_event(decomp->head, decomp->size, decomp->data, + session->header.needs_swap); if (!event) break; @@ -2100,7 +2110,7 @@ remap: } more: - event = fetch_mmaped_event(session, head, mmap_size, buf); + event = fetch_mmaped_event(head, mmap_size, buf, session->header.needs_swap); if (IS_ERR(event)) return PTR_ERR(event);