perf: Treat attr.config as u64 in perf_swevent_init()

Trinity discovered that we fail to check all 64 bits of
attr.config passed by user space, resulting to out-of-bounds
access of the perf_swevent_enabled array in
sw_perf_event_destroy().

Introduced in commit b0a873ebb ("perf: Register PMU
implementations").

Signed-off-by: Tommi Rantala <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Cc: Paul Mackerras <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 7e0962ed7f8ac850092323e56cbcb73a5a399a13..4d3124b392774322ae1b33f167a10c1046d886d9 100644 (file)
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -5331,7 +5331,7 @@ static void sw_perf_event_destroy(struct perf_event *event)
 
 static int perf_swevent_init(struct perf_event *event)
 {
-       int event_id = event->attr.config;
+       u64 event_id = event->attr.config;
 
        if (event->attr.type != PERF_TYPE_SOFTWARE)
                return -ENOENT;