From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: [PATCH 20/73] perf machine: Null-terminate version char array upon fgets(/proc/version) error Date: Fri, 17 May 2019 16:35:18 -0300 Message-ID: <20190517193611.4974-21-acme@kernel.org> References: <20190517193611.4974-1-acme@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190517193611.4974-1-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: Ingo Molnar , Thomas Gleixner Cc: Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Donald Yandt , Alexander Shishkin , Avi Kivity , Jiri Olsa , Peter Zijlstra , Yanmin Zhang , Arnaldo Carvalho de Melo List-Id: linux-perf-users.vger.kernel.org From: Donald Yandt If fgets() fails due to any other error besides end-of-file, the version char array may not even be null-terminated. Signed-off-by: Donald Yandt Cc: Alexander Shishkin Cc: Avi Kivity Cc: Jiri Olsa Cc: Peter Zijlstra Cc: Yanmin Zhang Fixes: a1645ce12adb ("perf: 'perf kvm' tool for monitoring guest performance from host") Link: http://lkml.kernel.org/r/20190514110100.22019-1-donald.yandt@gmail.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/machine.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 3c520baa198c..28a9541c4835 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -1234,8 +1234,9 @@ static char *get_kernel_version(const char *root_dir) if (!file) return NULL; - version[0] = '\0'; tmp = fgets(version, sizeof(version), file); + if (!tmp) + *version = '\0'; fclose(file); name = strstr(version, prefix); -- 2.20.1