Re: [PATCHv3 1/7] blk-mq: introduce blk_map_iter
From: Kanchan Joshi <hidden>
Date: 2025-07-30 08:18:48
Also in:
linux-nvme
On 7/29/2025 8:04 PM, Keith Busch wrote:
quoted hunk ↗ jump to hunk
@@ -39,12 +33,11 @@ static bool blk_map_iter_next(struct request *req, struct req_iterator *iter, * one could be merged into it. This typically happens when moving to * the next bio, but some callers also don't pack bvecs tight. */ - while (!iter->iter.bi_size || !iter->iter.bi_bvec_done) { + while (!iter->iter.bi_size || + (!iter->iter.bi_bvec_done && iter->bio->bi_next)) { struct bio_vec next; if (!iter->iter.bi_size) { - if (!iter->bio->bi_next) - break; iter->bio = iter->bio->bi_next; iter->iter = iter->bio->bi_iter;
This can crash here if we come inside the loop because iter->iter.bi_size is 0 and if this is the last bio i.e., iter->bio->bi_next is NULL?