On 5/25/24 9:05 AM, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
>
> 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@xxxxxxxxxxxxxxx>.
>
> 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 3d8f874bd620ce03f75a5512847586828ab86544
> # <resolve conflicts, build, test, etc.>
> git commit -s
> git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2024052549-gyration-replica-129f@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Here's one for 5.4 stable, thanks.
--
Jens Axboe
From 4e819fc325982e330e36eaaa22896b2e8d778ba0 Mon Sep 17 00:00:00 2001
From: Ming Lei <ming.lei@xxxxxxxxxx>
Date: Fri, 10 May 2024 11:50:27 +0800
Subject: [PATCH] io_uring: fail NOP if non-zero op flags is passed in
Commit 3d8f874bd620ce03f75a5512847586828ab86544 upstream.
The NOP op flags should have been checked from beginning like any other
opcode, otherwise NOP may not be extended with the op flags.
Given both liburing and Rust io-uring crate always zeros SQE op flags, just
ignore users which play raw NOP uring interface without zeroing SQE, because
NOP is just for test purpose. Then we can save one NOP2 opcode.
Suggested-by: Jens Axboe <axboe@xxxxxxxxx>
Fixes: 2b188cc1bb85 ("Add io_uring IO interface")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240510035031.78874-2-ming.lei@xxxxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
fs/io_uring.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 2c793e4ccf09..4cfddd712452 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2112,6 +2112,8 @@ static int __io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
switch (req->submit.opcode) {
case IORING_OP_NOP:
+ if (READ_ONCE(s->sqe->rw_flags))
+ return -EINVAL;
ret = io_nop(req, req->user_data);
break;
case IORING_OP_READV:
--
2.43.0
