Merge tag 'block-6.12-20241101' of git://git.kernel.dk/linux

Pull block fixes from Jens Axboe:

 - Fixup for a recent blk_rq_map_user_bvec() patch

 - NVMe pull request via Keith:
     - Spec compliant identification fix (Keith)
     - Module parameter to enable backward compatibility on unusual
       namespace formats (Keith)
     - Target double free fix when using keys (Vitaliy)
     - Passthrough command error handling fix (Keith)

* tag 'block-6.12-20241101' of git://git.kernel.dk/linux:
  nvme: re-fix error-handling for io_uring nvme-passthrough
  nvmet-auth: assign dh_key to NULL after kfree_sensitive
  nvme: module parameter to disable pi with offsets
  block: fix queue limits checks in blk_rq_map_user_bvec for real
  nvme: enhance cns version checking

1 files changed, 17 insertions, 39 deletions

diff --git a/block/blk-map.c b/block/blk-map.c
index 6ef2ec1f7d78..b5fd1d857461 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -561,55 +561,33 @@ EXPORT_SYMBOL(blk_rq_append_bio);
 /* Prepare bio for passthrough IO given ITER_BVEC iter */
 static int blk_rq_map_user_bvec(struct request *rq, const struct iov_iter *iter)
 {
-	struct request_queue *q = rq->q;
-	size_t nr_iter = iov_iter_count(iter);
-	size_t nr_segs = iter->nr_segs;
-	struct bio_vec *bvecs, *bvprvp = NULL;
-	const struct queue_limits *lim = &q->limits;
-	unsigned int nsegs = 0, bytes = 0;
+	const struct queue_limits *lim = &rq->q->limits;
+	unsigned int max_bytes = lim->max_hw_sectors << SECTOR_SHIFT;
+	unsigned int nsegs;
 	struct bio *bio;
-	size_t i;
+	int ret;
 
-	if (!nr_iter || (nr_iter >> SECTOR_SHIFT) > queue_max_hw_sectors(q))
-		return -EINVAL;
-	if (nr_segs > queue_max_segments(q))
+	if (!iov_iter_count(iter) || iov_iter_count(iter) > max_bytes)
 		return -EINVAL;
 
-	/* no iovecs to alloc, as we already have a BVEC iterator */
+	/* reuse the bvecs from the iterator instead of allocating new ones */
 	bio = blk_rq_map_bio_alloc(rq, 0, GFP_KERNEL);
-	if (bio == NULL)
+	if (!bio)
 		return -ENOMEM;
-
 	bio_iov_bvec_set(bio, (struct iov_iter *)iter);
-	blk_rq_bio_prep(rq, bio, nr_segs);
-
-	/* loop to perform a bunch of sanity checks */
-	bvecs = (struct bio_vec *)iter->bvec;
-	for (i = 0; i < nr_segs; i++) {
-		struct bio_vec *bv = &bvecs[i];
-
-		/*
-		 * If the queue doesn't support SG gaps and adding this
-		 * offset would create a gap, fallback to copy.
-		 */
-		if (bvprvp && bvec_gap_to_prev(lim, bvprvp, bv->bv_offset)) {
-			blk_mq_map_bio_put(bio);
-			return -EREMOTEIO;
-		}
-		/* check full condition */
-		if (nsegs >= nr_segs || bytes > UINT_MAX - bv->bv_len)
-			goto put_bio;
-		if (bytes + bv->bv_len > nr_iter)
-			break;
 
-		nsegs++;
-		bytes += bv->bv_len;
-		bvprvp = bv;
+	/* check that the data layout matches the hardware restrictions */
+	ret = bio_split_rw_at(bio, lim, &nsegs, max_bytes);
+	if (ret) {
+		/* if we would have to split the bio, copy instead */
+		if (ret > 0)
+			ret = -EREMOTEIO;
+		blk_mq_map_bio_put(bio);
+		return ret;
 	}
+
+	blk_rq_bio_prep(rq, bio, nsegs);
 	return 0;
-put_bio:
-	blk_mq_map_bio_put(bio);
-	return -EINVAL;
 }
 
 /**