aio: fix possible invalid memory access when DEBUG is enabled

commit 91d80a84bbc8f28375cca7e65ec666577b4209ad upstream.

dprintk() shouldn't access @ring after it's unmapped.

Signed-off-by: Zhao Hongjiang <zhaohongjiang@huawei.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/aio.c b/fs/aio.c
index 71f613cf4a8..ed762aebb4a 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1027,9 +1027,9 @@ static int aio_read_evt(struct kioctx *ioctx, struct io_event *ent)
 	spin_unlock(&info->ring_lock);
 
 out:
-	kunmap_atomic(ring);
 	dprintk("leaving aio_read_evt: %d  h%lu t%lu\n", ret,
 		 (unsigned long)ring->head, (unsigned long)ring->tail);
+	kunmap_atomic(ring);
 	return ret;
 }