[PATCH AUTOSEL for 4.9 093/281] perf/core: Fix error handling in perf_event_alloc()

[Sasha Levin]

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit 36cc2b9222b5106de34085c4dd8635ac67ef5cba ]

We don't set an error code here which means that perf_event_alloc()
returns ERR_PTR(0) (in other words NULL).  The callers are not expecting
that and would Oops.

Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vince Weaver <vincent.weaver@xxxxxxxxx>
Fixes: 375637bc5249 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/20170522090418.hvs6icgpdo53wkn5@mwanda
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
 kernel/events/core.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 13b9784427b0..d7914fa6bc09 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -9289,8 +9289,10 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
 		event->addr_filters_offs = kcalloc(pmu->nr_addr_filters,
 						   sizeof(unsigned long),
 						   GFP_KERNEL);
-		if (!event->addr_filters_offs)
+		if (!event->addr_filters_offs) {
+			err = -ENOMEM;
 			goto err_per_task;
+		}
 
 		/* force hw sync on the address filters */
 		event->addr_filters_gen = 1;
-- 
2.14.1