[tip:perf/core] perf/core: Don't leak event in the syscall error path

[tip-bot for Alexander Shishkin <tipbot@zytor.com>]

Commit-ID:  201c2f85bd0bc13b712d9c0b3d11251b182e06ae
Gitweb:     http://git.kernel.org/tip/201c2f85bd0bc13b712d9c0b3d11251b182e06ae
Author:     Alexander Shishkin <alexander.shishkin@linux.intel.com>
AuthorDate: Mon, 21 Mar 2016 10:02:42 +0200
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Thu, 31 Mar 2016 09:54:07 +0200

perf/core: Don't leak event in the syscall error path

In the error path, event_file not being NULL is used to determine
whether the event itself still needs to be free'd, so fix it up to
avoid leaking.

Reported-by: Leon Yu <chianglungyu@gmail.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 130056275ade ("perf: Do not double free")
Link: http://lkml.kernel.org/r/87twk06yxp.fsf@ashishki-desk.ger.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/events/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 8c11388..52bedc5 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8542,6 +8542,7 @@ SYSCALL_DEFINE5(perf_event_open,
 					f_flags);
 	if (IS_ERR(event_file)) {
 		err = PTR_ERR(event_file);
+		event_file = NULL;
 		goto err_context;
 	}