From 5478755616ae2ef1ce144dded589b62b2a50d575 Mon Sep 17 00:00:00 2001 From: Xiaotian Feng Date: Mon, 29 Nov 2010 10:03:55 +0100 Subject: [PATCH] block: check for proper length of iov entries earlier in blk_rq_map_user_iov() commit 9284bcf checks for proper length of iov entries in blk_rq_map_user_iov(). But if the map is unaligned, kernel will break out the loop without checking for the proper length. So we need to check the proper length before the unalign check. Signed-off-by: Xiaotian Feng Cc: stable@kernel.org Signed-off-by: Jens Axboe --- block/blk-map.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/block/blk-map.c b/block/blk-map.c index 5d5dbe47c228..e663ac2d8e68 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -201,12 +201,13 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, for (i = 0; i < iov_count; i++) { unsigned long uaddr = (unsigned long)iov[i].iov_base; + if (!iov[i].iov_len) + return -EINVAL; + if (uaddr & queue_dma_alignment(q)) { unaligned = 1; break; } - if (!iov[i].iov_len) - return -EINVAL; } if (unaligned || (q->dma_pad_mask & len) || map_data) -- GitLab