FAILED: patch "[PATCH] io_uring: fix off-by one bvec index" failed to apply to 5.15-stable tree

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x d6fef34ee4d102be448146f24caf96d7b4a05401
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2023113024-dating-blog-e8e0@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

d6fef34ee4d1 ("io_uring: fix off-by one bvec index")
57bebf807e2a ("io_uring/rsrc: optimise registered huge pages") b000ae0ec2d7 ("io_uring/rsrc: optimise single entry advance") c059f7858408 ("io_uring: move io_import_fixed()")
f337a84d3952 ("io_uring: opcode independent fixed buf import") f3b44f92e59a ("io_uring: move read/write related opcodes to its own file") c98817e6cd44 ("io_uring: move remaining file table manipulation to filetable.c") 735729844819 ("io_uring: move rsrc related data, core, and commands") 3b77495a9723 ("io_uring: split provided buffers handling into its own file") 7aaff708a768 ("io_uring: move cancelation into its own file") 329061d3e2f9 ("io_uring: move poll handling into its own file") cfd22e6b3319 ("io_uring: add opcode name to io_op_defs") 92ac8beaea1f ("io_uring: include and forward-declaration sanitation") c9f06aa7de15 ("io_uring: move io_uring_task (tctx) helpers into its own file") a4ad4f748ea9 ("io_uring: move fdinfo helpers to its own file") e5550a1447bf ("io_uring: use io_is_uring_fops() consistently") 17437f311490 ("io_uring: move SQPOLL related handling into its own file") 59915143e89f ("io_uring: move timeout opcodes and handling into its own file") e418bbc97bff ("io_uring: move our reference counting into a header") 36404b09aa60 ("io_uring: move msg_ring into its own file")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From d6fef34ee4d102be448146f24caf96d7b4a05401 Mon Sep 17 00:00:00 2001
From: Keith Busch <[email protected]>
Date: Mon, 20 Nov 2023 14:18:31 -0800
Subject: [PATCH] io_uring: fix off-by one bvec index

If the offset equals the bv_len of the first registered bvec, then the request does not include any of that first bvec. Skip it so that drivers don't have to deal with a zero length bvec, which was observed to break NVMe's PRP list creation.

index 7034be555334..f521c5965a93 100644
@@ -1258,7 +1258,7 @@ int io_import_fixed(int ddir, struct iov_iter *iter,
 		 */
 		const struct bio_vec *bvec = imu->bvec;
 
-		if (offset <= bvec->bv_len) {
+		if (offset < bvec->bv_len) {
 			/*
 			 * Note, huge pages buffers consists of one large
 			 * bvec entry and should always go this way. The other

And here's one for both 5.10 and 5.15 stable.

Jens Axboe

From 4581de67b1393426ac29d8c6d19119e15f08a313 Mon Sep 17 00:00:00 2001
From: Keith Busch <[email protected]>
Date: Mon, 20 Nov 2023 14:18:31 -0800
Subject: [PATCH 2/2] io_uring: fix off-by one bvec index

commit d6fef34ee4d102be448146f24caf96d7b4a05401 upstream.

If the offset equals the bv_len of the first registered bvec, then the request does not include any of that first bvec. Skip it so that drivers don't have to deal with a zero length bvec, which was observed to break NVMe's PRP list creation.

---
 io_uring/io_uring.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 3ddb95483746..38e202b81287 100644
@@ -3152,7 +3152,7 @@ static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter
 		 */
 		const struct bio_vec *bvec = imu->bvec;
 
-		if (offset <= bvec->bv_len) {
+		if (offset < bvec->bv_len) {
 			iov_iter_advance(iter, offset);
 		} else {
 			unsigned long seg_skip;

2.42.0