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@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-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@vger.kernel.org' --in-reply-to '167931300423217@kroah.com' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:

5da28edd7bd5 ("io_uring/msg_ring: let target know allocated index") 172113101641 ("io_uring: extract a io_msg_install_complete helper") 11373026f296 ("io_uring: get rid of double locking") b529c96a896b ("io_uring: remove overflow param from io_post_aux_cqe") a77ab745f28d ("io_uring: make io_fill_cqe_aux static") 9b8c54755a2b ("io_uring: add io_aux_cqe which allows deferred completion") 931147ddfa6e ("io_uring: allow defer completion for aux posted cqes") 1bec951c3809 ("io_uring: iopoll protect complete_post") fa18fa2272c7 ("io_uring: inline __io_req_complete_put()") f9d567c75ec2 ("io_uring: inline __io_req_complete_post()") e2ad599d1ed3 ("io_uring: allow multishot recv CQEs to overflow") 515e26961295 ("io_uring: revert "io_uring fix multishot accept ordering"")

thanks,

greg k-h

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

From 5da28edd7bd5518f97175ecea77615bb729a7a28 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov asml.silence@gmail.com Date: Thu, 16 Mar 2023 12:11:42 +0000 Subject: [PATCH] io_uring/msg_ring: let target know allocated index

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@vger.kernel.org # v6.0+ Fixes: e6130eba8a848 ("io_uring: add support for passing fixed file descriptors") Signed-off-by: Pavel Begunkov asml.silence@gmail.com Link: https://github.com/axboe/liburing/issues/809 Signed-off-by: Jens Axboe axboe@kernel.dk

diff --git a/io_uring/msg_ring.c b/io_uring/msg_ring.c index 8803c0979e2a..85fd7ce5f05b 100644 --- a/io_uring/msg_ring.c +++ b/io_uring/msg_ring.c @@ -202,7 +202,7 @@ static int io_msg_install_complete(struct io_kiocb *req, unsigned int issue_flag * 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)) + if (!io_post_aux_cqe(target_ctx, msg->user_data, ret, 0)) ret = -EOVERFLOW; out_unlock: io_double_unlock_ctx(target_ctx); @@ -229,6 +229,8 @@ static int io_msg_send_fd(struct io_kiocb *req, unsigned int issue_flags) struct io_ring_ctx *ctx = req->ctx; struct file *src_file = msg->src_file;

+ if (msg->len) + return -EINVAL; if (target_ctx == ctx) return -EINVAL; if (target_ctx->flags & IORING_SETUP_R_DISABLED)