From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELt3sXdt39pdGsHvIMd7gIj3w3bcva758MiAAuswKRX+0x9HeYd4+tjWXtJmfB5PnR5ZZAmV ARC-Seal: i=1; a=rsa-sha256; t=1521483753; cv=none; d=google.com; s=arc-20160816; b=nlLVBhknuYn8nwJUwiqj93s7wWSK613Fw/8/h3Dl/QoeexgpjaWmqZQHGZieTeoCCt 5t8cRuo205V146lBmNAv1Fa6kOuJ+ln/1XtfEtn7Cy0eyb2GCGR43+qFFH5hWJ00GWeN 22oyIXDGfKLy9EDXGLguxaxxZ10e5pzOtOlDy8x9lcLqRNPDj5M6RbFocihkPMQs4JPh OSqbDIEaizCyZ0XXGZrNoEKFnrHiuisGbR1v8kWbynwrRHZ5jHuAdhO3jsbJI7IAa8bd mdO5JidN/NN22+wVxeLYFGnYH6PB7FAISx53PGevx6vyduqtGl/PluXkwmNFB54Bhv6f PzpQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=s6SjzCic3RjrWlRQ1eD9sWaxqbiLJ0aZnln4xRFaJas=; b=ZryPeS4JCKDuoyR72AO5pZrwlwWalY9L8JaqJWbdSTSy8g83gDFdhVjXXc6y4l8x0k IZU7ldwxnF89WGwSsCsTZtqnQYWMpJlPv03wP0+GWCkYGCLBfnsjjNvcHvOf06iu+U+f Ct59E4t6qwD2ZZUoJ+YKN7irbpZu2PNcBF1JuZtj7NOqu0GfFSdqHl7EStP0aCvSi3nh ysONi8ZM8PYeIl+gm2y8ZghRBgMO1rtj3XYkyB+HX0hXMr2D0dy5sp038Ypx5gPfhZdj em2/rmSPjmv/pezbSMcO/hjkv7XyxcVpourCMrblFZWp2CcTeF3E4bVMKsqVcqbRrPY3 aeDw== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tommi Rantala , Alexander Shishkin , Peter Zijlstra , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH 4.9 069/241] perf buildid: Do not assume that readlink() returns a null terminated string Date: Mon, 19 Mar 2018 19:05:34 +0100 Message-Id: <20180319180754.063574728@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180319180751.172155436@linuxfoundation.org> References: <20180319180751.172155436@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1595391348080703478?= X-GMAIL-MSGID: =?utf-8?q?1595391348080703478?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ 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)) {