[PATCH 4.17 075/324] blk-mq-debugfs: Off by one in blk_mq_rq_state_name()

[Greg Kroah-Hartman]

4.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit a1e79188628580465ac6d7a93a313336ee3364f1 ]

If rq_state == ARRAY_SIZE() then we read one element beyond the end of
the blk_mq_rq_state_name_array[] array.

Fixes: ec6dcf63c55c ("blk-mq-debugfs: Show more request state information")
Reviewed-by: Bart Van Assche <bart.vanassche@xxxxxxx>
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 block/blk-mq-debugfs.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -357,7 +357,7 @@ static const char *const blk_mq_rq_state
 
 static const char *blk_mq_rq_state_name(enum mq_rq_state rq_state)
 {
-	if (WARN_ON_ONCE((unsigned int)rq_state >
+	if (WARN_ON_ONCE((unsigned int)rq_state >=
 			 ARRAY_SIZE(blk_mq_rq_state_name_array)))
 		return "(?)";
 	return blk_mq_rq_state_name_array[rq_state];