From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:43724 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754564AbeCRQEa (ORCPT ); Sun, 18 Mar 2018 12:04:30 -0400 Subject: Patch "perf buildid: Do not assume that readlink() returns a null terminated string" has been added to the 4.9-stable tree To: tommi.t.rantala@nokia.com, acme@redhat.com, alexander.levin@microsoft.com, alexander.shishkin@linux.intel.com, gregkh@linuxfoundation.org, peterz@infradead.org Cc: , From: Date: Sun, 18 Mar 2018 17:03:00 +0100 Message-ID: <15213889807040@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled perf buildid: Do not assume that readlink() returns a null terminated string to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: perf-buildid-do-not-assume-that-readlink-returns-a-null-terminated-string.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Sun Mar 18 16:55:33 CET 2018 From: Tommi Rantala Date: Wed, 22 Mar 2017 15:06:20 +0200 Subject: perf buildid: Do not assume that readlink() returns a null terminated string From: Tommi Rantala [ Upstream commit 5a2342111c68e623e27ee7ea3d0492d8dad6bda0 ] Valgrind was complaining: $ valgrind ./perf list >/dev/null ==11643== Memcheck, a memory error detector ==11643== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al. ==11643== Using Valgrind-3.12.0 and LibVEX; rerun with -h for copyright info ==11643== Command: ./perf list ==11643== ==11643== Conditional jump or move depends on uninitialised value(s) ==11643== at 0x4C30620: rindex (vg_replace_strmem.c:199) ==11643== by 0x49DAA9: build_id_cache__origname (build-id.c:198) ==11643== by 0x49E1C7: build_id_cache__valid_id (build-id.c:222) ==11643== by 0x49E1C7: build_id_cache__list_all (build-id.c:507) ==11643== by 0x4B9C8F: print_sdt_events (parse-events.c:2067) ==11643== by 0x4BB0B3: print_events (parse-events.c:2313) ==11643== by 0x439501: cmd_list (builtin-list.c:53) ==11643== by 0x497150: run_builtin (perf.c:359) ==11643== by 0x428CE0: handle_internal_command (perf.c:421) ==11643== by 0x428CE0: run_argv (perf.c:467) ==11643== by 0x428CE0: main (perf.c:614) [...] Additionally, a zero length result from readlink() is not very interesting. Signed-off-by: Tommi Rantala Cc: Alexander Shishkin Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20170322130624.21881-3-tommi.t.rantala@nokia.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/build-id.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/tools/perf/util/build-id.c +++ b/tools/perf/util/build-id.c @@ -182,13 +182,17 @@ char *build_id_cache__origname(const cha char buf[PATH_MAX]; char *ret = NULL, *p; size_t offs = 5; /* == strlen("../..") */ + ssize_t len; linkname = build_id_cache__linkname(sbuild_id, NULL, 0); if (!linkname) return NULL; - if (readlink(linkname, buf, PATH_MAX) < 0) + len = readlink(linkname, buf, sizeof(buf) - 1); + if (len <= 0) goto out; + buf[len] = '\0'; + /* The link should be "../../" */ p = strrchr(buf, '/'); /* Cut off the "/" */ if (p && (p > buf + offs)) { Patches currently in stable-queue which might be from tommi.t.rantala@nokia.com are queue-4.9/perf-buildid-do-not-assume-that-readlink-returns-a-null-terminated-string.patch