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>
(cherry picked from commit 201c2f85bd0bc13b712d9c0b3d11251b182e06ae)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index c22f4579a2e75821a5cb0709e5e6e36fe6a4f6f5..b296032a2c4e6ae020473a3e93470e96f746fc5d 100644 (file)
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8457,6 +8457,7 @@ SYSCALL_DEFINE5(perf_event_open,
                                        f_flags);
        if (IS_ERR(event_file)) {
                err = PTR_ERR(event_file);
+               event_file = NULL;
                goto err_context;
        }