From: Ravi Bangoria <[email protected]>
[ Upstream commit 913a90bc5a3a06b1f04c337320e9aeee2328dd77 ]
perf_event_open() limits the sample_period to 63 bits. See:
0819b2e30ccb ("perf: Limit perf_event_attr::sample_period to 63 bits")
Make ioctl() consistent with it.
Also on PowerPC, negative sample_period could cause a recursive
PMIs leading to a hang (reported when running perf-fuzzer).
Signed-off-by: Ravi Bangoria <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vince Weaver <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Fixes: 0819b2e30ccb ("perf: Limit perf_event_attr::sample_period to 63 bits")
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
kernel/events/core.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 751888cbed5c..16af86ab24c4 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -5012,6 +5012,9 @@ static int perf_event_period(struct perf_event *event,
u64 __user *arg)
if (perf_event_check_period(event, value))
return -EINVAL;
+ if (!event->attr.freq && (value & (1ULL << 63)))
+ return -EINVAL;
+
event_function_call(event, __perf_event_period, &value);
return 0;
--
2.20.1
