Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
kernel/events/core.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -5762,6 +5762,11 @@ static inline struct fd perf_fdget(int f
return f;
}
+static inline bool is_perf_fd(struct fd fd)
+{
+ return fd.file && fd.file->f_op == &perf_fops;
+}
+
static int perf_event_set_output(struct perf_event *event,
struct perf_event *output_event);
static int perf_event_set_filter(struct perf_event *event, void __user *arg);
@@ -5807,19 +5812,15 @@ static long _perf_ioctl(struct perf_even
case PERF_EVENT_IOC_SET_OUTPUT:
{
- int ret;
if (arg != -1) {
struct perf_event *output_event;
- struct fd output = perf_fdget(arg);
- if (!output.file)
+ CLASS(fd, output)(arg);
+ if (!is_perf_fd(output))
return -EBADF;
output_event = output.file->private_data;
- ret = perf_event_set_output(event, output_event);
- fdput(output);
- } else {
- ret = perf_event_set_output(event, NULL);
+ return perf_event_set_output(event, output_event);
}
- return ret;
+ return perf_event_set_output(event, NULL);
}
case PERF_EVENT_IOC_SET_FILTER:
