[PATCH 7/7] perf: Make rb_alloc_aux() return an error immediately if nr_pages <= 0

[Adrian Hunter]

rb_alloc_aux() should not be called with nr_pages <= 0. Make it more robust
and readable by returning an error immediately in that case.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
 kernel/events/ring_buffer.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 485cf0a66631..8cadf97bc290 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -682,6 +682,9 @@ int rb_alloc_aux(struct perf_buffer *rb, struct perf_event *event,
 	if (!has_aux(event))
 		return -EOPNOTSUPP;
 
+	if (nr_pages <= 0)
+		return -EINVAL;
+
 	if (!overwrite) {
 		/*
 		 * Watermark defaults to half the buffer, and so does the
-- 
2.34.1