Commit 38349665 authored Oct 06, 2015 by Andrzej Hajda Committed by Arnaldo Carvalho de Melo Oct 06, 2015

perf tools: Fix handling read result using a signed variable

The function can return negative value, assigning it to unsigned
variable can cause memory corruption.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2038576



Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/1444122017-16856-1-git-send-email-a.hajda@samsung.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 1178bfd4

tools/perf/util/event.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -67,7 +67,8 @@ static int perf_event__get_comm_ids(pid_t pid, char *comm, size_t len,
		char filename[PATH_MAX];
		char bf[4096];
		int fd;
		size_t size = 0, n;
		size_t size = 0;
		ssize_t n;
		char nl, name, tgids, ppids;

		*tgid = -1;