diff options
author | Pavel Begunkov <asml.silence@gmail.com> | 2023-09-14 18:51:09 +0300 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2023-09-14 19:12:55 +0300 |
commit | c21a8027ad8a68c340d0d58bf1cc61dcb0bc4d2f (patch) | |
tree | 840d2d18d307e2332f7a498ac854737e2621e66d | |
parent | 0bb80ecc33a8fb5a682236443c1e740d5c917d1d (diff) | |
download | linux-c21a8027ad8a68c340d0d58bf1cc61dcb0bc4d2f.tar.xz |
io_uring/net: fix iter retargeting for selected buf
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@vger.kernel.org
Reported-by: syzbot+a4c6e5ef999b68b26ed1@syzkaller.appspotmail.com
Fixes: 0455d4ccec548 ("io_uring: add POLL_FIRST support for send/sendmsg and recv/recvmsg")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0000000000002770be06053c7757@google.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r-- | io_uring/net.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/io_uring/net.c b/io_uring/net.c index 3d07bf79c1e0..7a8e298af81b 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -183,6 +183,10 @@ static int io_setup_async_msg(struct io_kiocb *req, 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 (iter_is_iovec(&kmsg->msg.msg_iter) && !kmsg->free_iov) { size_t fast_idx = iter_iov(&kmsg->msg.msg_iter) - kmsg->fast_iov; @@ -542,6 +546,7 @@ static int io_recvmsg_copy_hdr(struct io_kiocb *req, 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) |