Don't feed anything but regular iovec's to blk_rq_map_user_iov

In theory we could map other things, but there's a reason that function is called "user_iov". Using anything else (like splice can do) just confuses it. Reported-and-tested-by: Johannes Thumshirn <[email protected]> Cc: Al Viro <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
chewitt · Dec 7, 2016 · a0ac402 · a0ac402
1 parent bc3913a
commit a0ac402
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/block/blk-map.c b/block/blk-map.c
@@ -118,6 +118,9 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
 	struct iov_iter i;
 	int ret;
 
+	if (!iter_is_iovec(iter))
+		goto fail;
+
 	if (map_data)
 		copy = true;
 	else if (iov_iter_alignment(iter) & align)
@@ -140,6 +143,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
 
 unmap_rq:
 	__blk_rq_unmap_user(bio);
+fail:
 	rq->bio = NULL;
 	return -EINVAL;
 }