perf: Fix perf_event_open(.flags) test

Vince noticed that we test the (unsigned long) flags field against an
(unsigned int) constant. This would allow setting the high bits on 64bit
platforms and not get an error.

There is nothing that uses the high bits, so it should be entirely
harmless, but we don't want userspace to accidentally set them anyway,
so fix the constants.

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140423102254.GL11096@twins.programming.kicks-ass.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

include/uapi/linux/perf_event.h

@@ -722,10 +722,10 @@ enum perf_callchain_context {
 	PERF_CONTEXT_MAX		= (__u64)-4095,
 };
 
-#define PERF_FLAG_FD_NO_GROUP		(1U << 0)
-#define PERF_FLAG_FD_OUTPUT		(1U << 1)
-#define PERF_FLAG_PID_CGROUP		(1U << 2) /* pid=cgroup id, per-cpu mode only */
-#define PERF_FLAG_FD_CLOEXEC		(1U << 3) /* O_CLOEXEC */
+#define PERF_FLAG_FD_NO_GROUP		(1UL << 0)
+#define PERF_FLAG_FD_OUTPUT		(1UL << 1)
+#define PERF_FLAG_PID_CGROUP		(1UL << 2) /* pid=cgroup id, per-cpu mode only */
+#define PERF_FLAG_FD_CLOEXEC		(1UL << 3) /* O_CLOEXEC */
 
 union perf_mem_data_src {
 	__u64 val;