[PATCH 4.4 210/312] bpf, trace: check event type in bpf_perf_event_read

[Greg Kroah-Hartman]

From: Alexei Starovoitov <ast@xxxxxx>

commit ad572d174787daa59e24b8b5c83028c09cdb5ddb upstream.

similar to bpf_perf_event_output() the bpf_perf_event_read() helper
needs to check the type of the perf_event before reading the counter.

Fixes: a43eec304259 ("bpf: introduce bpf_perf_event_output() helper")
Reported-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Acked-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 kernel/trace/bpf_trace.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -206,6 +206,10 @@ static u64 bpf_perf_event_read(u64 r1, u
 	    event->pmu->count)
 		return -EINVAL;
 
+	if (unlikely(event->attr.type != PERF_TYPE_HARDWARE &&
+		     event->attr.type != PERF_TYPE_RAW))
+		return -EINVAL;
+
 	/*
 	 * we don't know if the function is run successfully by the
 	 * return value. It can be judged in other places, such as