On 3/20/23 5:50 AM, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
>
> The patch below does not apply to the 6.1-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-6.1.y
> git checkout FETCH_HEAD
> git cherry-pick -x 5da28edd7bd5518f97175ecea77615bb729a7a28
> # <resolve conflicts, build, test, etc.>
> git commit -s
> git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '167931300423217@xxxxxxxxx' --subject-prefix 'PATCH 6.1.y' HEAD^..
Here's a tested backport of that patch.
--
Jens Axboe
From 1b6b46b344561c9b5127bcc59c68a310d66f4368 Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <asml.silence@xxxxxxxxx>
Date: Mon, 20 Mar 2023 07:05:02 -0600
Subject: [PATCH] io_uring/msg_ring: let target know allocated index
commit 5da28edd7bd5518f97175ecea77615bb729a7a28 upstream.
msg_ring requests transferring files support auto index selection via
IORING_FILE_INDEX_ALLOC, however they don't return the selected index
to the target ring and there is no other good way for the userspace to
know where is the receieved file.
Return the index for allocated slots and 0 otherwise, which is
consistent with other fixed file installing requests.
Cc: stable@xxxxxxxxxxxxxxx # v6.0+
Fixes: e6130eba8a848 ("io_uring: add support for passing fixed file descriptors")
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
Link: https://github.com/axboe/liburing/issues/809
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
io_uring/msg_ring.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/io_uring/msg_ring.c b/io_uring/msg_ring.c
index 7d5b544cfc30..3526389ac218 100644
--- a/io_uring/msg_ring.c
+++ b/io_uring/msg_ring.c
@@ -84,6 +84,8 @@ static int io_msg_send_fd(struct io_kiocb *req, unsigned int issue_flags)
struct file *src_file;
int ret;
+ if (msg->len)
+ return -EINVAL;
if (target_ctx == ctx)
return -EINVAL;
if (target_ctx->flags & IORING_SETUP_R_DISABLED)
@@ -120,7 +122,7 @@ static int io_msg_send_fd(struct io_kiocb *req, unsigned int issue_flags)
* completes with -EOVERFLOW, then the sender must ensure that a
* later IORING_OP_MSG_RING delivers the message.
*/
- if (!io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0, true))
+ if (!io_post_aux_cqe(target_ctx, msg->user_data, ret, 0, true))
ret = -EOVERFLOW;
out_unlock:
io_double_unlock_ctx(ctx, target_ctx, issue_flags);
--
2.39.2
