From 4ac9690d4b9456ca1d5276d86547fa2e7cd47684 Mon Sep 17 00:00:00 2001 From: Florian-Ewald Mueller Date: Fri, 5 Dec 2025 13:47:32 +0100 Subject: [PATCH] rnbd-srv: Fix server side setting of bi_size for special IOs On rnbd-srv, the bi_size of the bio is set during the bio_add_page function, to which datalen is passed. But for special IOs like DISCARD and WRITE_ZEROES, datalen is 0, since there is no data to write. For these special IOs, use the bi_size of the rnbd_msg_io. Fixes: f6f84be089c9 ("block/rnbd-srv: Add sanity check and remove redundant assignment") Signed-off-by: Florian-Ewald Mueller Signed-off-by: Md Haris Iqbal Signed-off-by: Grzegorz Prajsner Signed-off-by: Jens Axboe --- drivers/block/rnbd/rnbd-srv.c | 33 +++++++++++++++++++++++---------- 1 file changed, 23 insertions(+), 10 deletions(-) diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c index 2df8941a6b146..9b3fdc202e152 100644 --- a/drivers/block/rnbd/rnbd-srv.c +++ b/drivers/block/rnbd/rnbd-srv.c @@ -145,18 +145,30 @@ static int process_rdma(struct rnbd_srv_session *srv_sess, priv->sess_dev = sess_dev; priv->id = id; - bio = bio_alloc(file_bdev(sess_dev->bdev_file), 1, + bio = bio_alloc(file_bdev(sess_dev->bdev_file), !!datalen, rnbd_to_bio_flags(le32_to_cpu(msg->rw)), GFP_KERNEL); - bio_add_virt_nofail(bio, data, datalen); - - bio->bi_opf = rnbd_to_bio_flags(le32_to_cpu(msg->rw)); - if (bio_has_data(bio) && - bio->bi_iter.bi_size != le32_to_cpu(msg->bi_size)) { - rnbd_srv_err_rl(sess_dev, "Datalen mismatch: bio bi_size (%u), bi_size (%u)\n", - bio->bi_iter.bi_size, msg->bi_size); - err = -EINVAL; - goto bio_put; + if (unlikely(!bio)) { + err = -ENOMEM; + goto put_sess_dev; } + + if (!datalen) { + /* + * For special requests like DISCARD and WRITE_ZEROES, the datalen is zero. + */ + bio->bi_iter.bi_size = le32_to_cpu(msg->bi_size); + } else { + bio_add_virt_nofail(bio, data, datalen); + bio->bi_opf = rnbd_to_bio_flags(le32_to_cpu(msg->rw)); + if (bio->bi_iter.bi_size != le32_to_cpu(msg->bi_size)) { + rnbd_srv_err_rl(sess_dev, + "Datalen mismatch: bio bi_size (%u), bi_size (%u)\n", + bio->bi_iter.bi_size, msg->bi_size); + err = -EINVAL; + goto bio_put; + } + } + bio->bi_end_io = rnbd_dev_bi_end_io; bio->bi_private = priv; bio->bi_iter.bi_sector = le64_to_cpu(msg->sector); @@ -170,6 +182,7 @@ static int process_rdma(struct rnbd_srv_session *srv_sess, bio_put: bio_put(bio); +put_sess_dev: rnbd_put_sess_dev(sess_dev); err: kfree(priv); -- 2.47.3