FAILED: patch "[PATCH] io_uring: fix off-by one bvec index" failed to apply to 5.4-stable tree

FAILED: patch "[PATCH] io_uring: fix off-by one bvec index" failed to apply to 5.4-stable tree

[gregkh]

The patch below does not apply to the 5.4-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 <stable@vger.kernel.org>.

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-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x d6fef34ee4d102be448146f24caf96d7b4a05401
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2023113025-eastbound-uninstall-c2e0@gregkh' --subject-prefix 'PATCH 5.4.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 <kbusch@kernel.org>
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.

Cc: stable@vger.kernel.org
Fixes: bd11b3a391e3 ("io_uring: don't use iov_iter_advance() for fixed buffers")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20231120221831.2646460-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
index 7034be555334..f521c5965a93 100644
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -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

Re: FAILED: patch "[PATCH] io_uring: fix off-by one bvec index" failed to apply to 5.4-stable tree

[Jens Axboe]

[-- Attachment #1: Type: text/plain, Size: 163 bytes --]

On 11/30/23 7:31 AM, gregkh@linuxfoundation.org wrote:
> 
> The patch below does not apply to the 5.4-stable tree.

And the 5.4 variant attached.

-- 
Jens Axboe


[-- Attachment #2: 5.4-io_uring-fix-off-by-one-bvec-index.patch --]
[-- Type: text/x-patch, Size: 1259 bytes --]

From aa4df1efa47241f8b9faab93f9d73eda4aa9ccf3 Mon Sep 17 00:00:00 2001
From: Keith Busch <kbusch@kernel.org>
Date: Mon, 20 Nov 2023 14:18:31 -0800
Subject: [PATCH] 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.

Cc: stable@vger.kernel.org
Fixes: bd11b3a391e3 ("io_uring: don't use iov_iter_advance() for fixed buffers")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20231120221831.2646460-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 fs/io_uring.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 3683ddeb625a..adc263400471 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1256,7 +1256,7 @@ static int io_import_fixed(struct io_ring_ctx *ctx, int rw,
 		 */
 		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

Re: FAILED: patch "[PATCH] io_uring: fix off-by one bvec index" failed to apply to 5.4-stable tree

[Greg KH]

On Thu, Nov 30, 2023 at 07:36:17AM -0700, Jens Axboe wrote:
> On 11/30/23 7:31 AM, gregkh@linuxfoundation.org wrote:
> > 
> > The patch below does not apply to the 5.4-stable tree.
> 
> And the 5.4 variant attached.

Thanks, all backports now queued up.

greg k-h