perf/core: Fix event inheritance on fork()
authorPeter Zijlstra <peterz@infradead.org>
Thu, 16 Mar 2017 12:47:49 +0000 (13:47 +0100)
committerIngo Molnar <mingo@kernel.org>
Thu, 16 Mar 2017 13:16:52 +0000 (14:16 +0100)
commite7cc4865f0f31698ef2f7aac01a50e78968985b7
tree5b4aa9c70956b5bc7b6e62edb00f2b14d007e62d
parente552a8389aa409e257b7dcba74f67f128f979ccc
perf/core: Fix event inheritance on fork()

While hunting for clues to a use-after-free, Oleg spotted that
perf_event_init_context() can loose an error value with the result
that fork() can succeed even though we did not fully inherit the perf
event context.

Spotted-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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>
Cc: oleg@redhat.com
Cc: stable@vger.kernel.org
Fixes: 889ff0150661 ("perf/core: Split context's event group list into pinned and non-pinned lists")
Link: http://lkml.kernel.org/r/20170316125823.190342547@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
kernel/events/core.c