Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754403AbdHDXmk (ORCPT ); Fri, 4 Aug 2017 19:42:40 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:49320 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754123AbdHDX2L (ORCPT ); Fri, 4 Aug 2017 19:28:11 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Markus Trippelsdorf , Adrian Hunter , David Ahern , Jiri Olsa , Namhyung Kim , Wang Nan , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH 4.4 80/91] perf symbols: Robustify reading of build-id from sysfs Date: Fri, 4 Aug 2017 16:16:16 -0700 Message-Id: <20170804231600.328837447@linuxfoundation.org> X-Mailer: git-send-email 2.13.4 In-Reply-To: <20170804231555.678888089@linuxfoundation.org> References: <20170804231555.678888089@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1499 Lines: 44 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ 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 Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/symbol-elf.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -488,6 +488,12 @@ int sysfs__read_build_id(const char *fil 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; }