blk-mq-debugfs: Off by one in blk_mq_rq_state_name()

[ 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@wdc.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 3080e18cb8590538084615d368b968ff8349ed9a..62b5f3f21b4b8c4f6bd62ce457cb9dc103d58e7e 100644 (file)
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -357,7 +357,7 @@ static const char *const blk_mq_rq_state_name_array[] = {
 
 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];