This is a note to let you know that I've just added the patch titled
io_uring/net: fix iter retargeting for selected buf
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
io_uring-net-fix-iter-retargeting-for-selected-buf.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From c21a8027ad8a68c340d0d58bf1cc61dcb0bc4d2f Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <asml.silence@xxxxxxxxx>
Date: Thu, 14 Sep 2023 16:51:09 +0100
Subject: io_uring/net: fix iter retargeting for selected buf
From: Pavel Begunkov <asml.silence@xxxxxxxxx>
commit c21a8027ad8a68c340d0d58bf1cc61dcb0bc4d2f upstream.
When using selected buffer feature, io_uring delays data iter setup
until later. If io_setup_async_msg() is called before that it might see
not correctly setup iterator. Pre-init nr_segs and judge from its state
whether we repointing.
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: syzbot+a4c6e5ef999b68b26ed1@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 0455d4ccec548 ("io_uring: add POLL_FIRST support for send/sendmsg and recv/recvmsg")
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
Link: https://lore.kernel.org/r/0000000000002770be06053c7757@xxxxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
io_uring/net.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -170,6 +170,10 @@ static int io_setup_async_msg(struct io_
memcpy(async_msg, kmsg, sizeof(*kmsg));
if (async_msg->msg.msg_name)
async_msg->msg.msg_name = &async_msg->addr;
+
+ if ((req->flags & REQ_F_BUFFER_SELECT) && !async_msg->msg.msg_iter.nr_segs)
+ return -EAGAIN;
+
/* if were using fast_iov, set it to the new one */
if (!kmsg->free_iov) {
size_t fast_idx = kmsg->msg.msg_iter.iov - kmsg->fast_iov;
@@ -529,6 +533,7 @@ static int io_recvmsg_copy_hdr(struct io
struct io_async_msghdr *iomsg)
{
iomsg->msg.msg_name = &iomsg->addr;
+ iomsg->msg.msg_iter.nr_segs = 0;
#ifdef CONFIG_COMPAT
if (req->ctx->compat)
Patches currently in stable-queue which might be from asml.silence@xxxxxxxxx are
queue-6.1/io_uring-net-fix-iter-retargeting-for-selected-buf.patch
