We were checking for iter to be NULL after dereferencing it. There is actually no need to check for iter to be NULL as all the callers of blk_rq_map_user_iov() does call it with a valid pointer to struct iov_iter. But as iter->count can be NULL so the assignment to copy is being done after checking for it.
Signed-off-by: Sudip Mukherjee <[email protected]> --- v2: removed the check for iter v1: moved the assignment to copy after check for iter and iter->count 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 a54f054..e15b4aa 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -126,14 +126,15 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, const struct iov_iter *iter, gfp_t gfp_mask) { struct iovec iov, prv = {.iov_base = NULL, .iov_len = 0}; - bool copy = (q->dma_pad_mask & iter->count) || map_data; + bool copy; struct bio *bio = NULL; struct iov_iter i; int ret; - if (!iter || !iter->count) + if (!iter->count) return -EINVAL; + copy = (q->dma_pad_mask & iter->count) || map_data; iov_for_each(iov, i, *iter) { unsigned long uaddr = (unsigned long) iov.iov_base; -- 2.1.4
