From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751568AbdGOBlD (ORCPT ); Fri, 14 Jul 2017 21:41:03 -0400 Received: from omzsmtpe01.verizonbusiness.com ([199.249.25.210]:25549 "EHLO omzsmtpe01.verizonbusiness.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751395AbdGOB1P (ORCPT ); Fri, 14 Jul 2017 21:27:15 -0400 X-IronPort-Anti-Spam-Filtered: false From: "Levin, Alexander (Sasha Levin)" Cc: Arnaldo Carvalho de Melo , Adrian Hunter , David Ahern , Jiri Olsa , Namhyung Kim , Wang Nan , "Levin, Alexander (Sasha Levin)" X-Host: discovery.odc.vzwcorp.com To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: [PATCH for v4.9 LTS 41/87] perf symbols: Robustify reading of build-id from sysfs Thread-Topic: [PATCH for v4.9 LTS 41/87] perf symbols: Robustify reading of build-id from sysfs Thread-Index: AQHS/QlXcwMrEQqP1UmoNV7q/hHmdQ== Date: Sat, 15 Jul 2017 01:26:11 +0000 Message-ID: <20170715012538.10101-41-alexander.levin@verizon.com> References: <20170715012538.10101-1-alexander.levin@verizon.com> In-Reply-To: <20170715012538.10101-1-alexander.levin@verizon.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.144.60.250] Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by nfs id v6F1f8s0023301 From: Arnaldo Carvalho de Melo [ Upstream commit 7934c98a6e04028eb34c1293bfb5a6b0ab630b66 ] Markus reported that perf segfaults when reading /sys/kernel/notes from a kernel linked with GNU gold, due to what looks like a gold bug, so do some bounds checking to avoid crashing in that case. Reported-by: Markus Trippelsdorf Report-Link: http://lkml.kernel.org/r/20161219161821.GA294@x4 Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-ryhgs6a6jxvz207j2636w31c@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/util/symbol-elf.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 99400b0e8f2a..adbc6c02c3aa 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -537,6 +537,12 @@ int sysfs__read_build_id(const char *filename, void *build_id, size_t size) break; } else { int n = namesz + descsz; + + if (n > (int)sizeof(bf)) { + n = sizeof(bf); + pr_debug("%s: truncating reading of build id in sysfs file %s: n_namesz=%u, n_descsz=%u.\n", + __func__, filename, nhdr.n_namesz, nhdr.n_descsz); + } if (read(fd, bf, n) != n) break; } -- 2.11.0