6.15-stable review patch. If anyone has any objections, please let me know.
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From: Pavel Begunkov asml.silence@gmail.com
commit c7cafd5b81cc07fb402e3068d134c21e60ea688c upstream.
8c8492ca64e7 ("io_uring/net: don't retry connect operation on EPOLLERR") is a little dirty hack that 1) wrongfully assumes that POLLERR equals to a failed request, which breaks all POLLERR users, e.g. all error queue recv interfaces. 2) deviates the connection request behaviour from connect(2), and 3) racy and solved at a wrong level.
Nothing can be done with 2) now, and 3) is beyond the scope of the patch. At least solve 1) by moving the hack out of generic poll handling into io_connect().
Cc: stable@vger.kernel.org Fixes: 8c8492ca64e79 ("io_uring/net: don't retry connect operation on EPOLLERR") Signed-off-by: Pavel Begunkov asml.silence@gmail.com Link: https://lore.kernel.org/r/3dc89036388d602ebd84c28e5042e457bdfc952b.175268244... Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- io_uring/net.c | 12 ++++++++---- io_uring/poll.c | 2 -- 2 files changed, 8 insertions(+), 6 deletions(-)
--- a/io_uring/net.c +++ b/io_uring/net.c @@ -1749,9 +1749,11 @@ int io_connect(struct io_kiocb *req, uns int ret; bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
- if (unlikely(req->flags & REQ_F_FAIL)) { - ret = -ECONNRESET; - goto out; + if (connect->in_progress) { + struct poll_table_struct pt = { ._key = EPOLLERR }; + + if (vfs_poll(req->file, &pt) & EPOLLERR) + goto get_sock_err; }
file_flags = force_nonblock ? O_NONBLOCK : 0; @@ -1776,8 +1778,10 @@ int io_connect(struct io_kiocb *req, uns * which means the previous result is good. For both of these, * grab the sock_error() and use that for the completion. */ - if (ret == -EBADFD || ret == -EISCONN) + if (ret == -EBADFD || ret == -EISCONN) { +get_sock_err: ret = sock_error(sock_from_file(req->file)->sk); + } } if (ret == -ERESTARTSYS) ret = -EINTR; --- a/io_uring/poll.c +++ b/io_uring/poll.c @@ -273,8 +273,6 @@ static int io_poll_check_events(struct i return IOU_POLL_REISSUE; } } - if (unlikely(req->cqe.res & EPOLLERR)) - req_set_fail(req); if (req->apoll_events & EPOLLONESHOT) return IOU_POLL_DONE;