6.15-stable review patch. If anyone has any objections, please let me know.
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From: Jens Axboe axboe@kernel.dk
commit 2c7f023219966777be0687e15b57689894304cd3 upstream.
Currently retry and general validity of msg_inq is gated on it being larger than zero, but it's entirely possible for this to be slightly inaccurate. In particular, if FIN is received, it'll return 1.
Just use larger than 1 as the check. This covers both the FIN case, and at the same time, it doesn't make much sense to retry a recv immediately if there's even just a single 1 byte of valid data in the socket.
Leave the SOCK_NONEMPTY flagging when larger than 0 still, as an app may use that for the final receive.
Cc: stable@vger.kernel.org Reported-by: Christian Mazakas christian.mazakas@gmail.com Fixes: 7c71a0af81ba ("io_uring/net: improve recv bundles") Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- io_uring/net.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/io_uring/net.c +++ b/io_uring/net.c @@ -840,7 +840,7 @@ static inline bool io_recv_finish(struct * If more is available AND it was a full transfer, retry and * append to this one */ - if (!sr->retry && kmsg->msg.msg_inq > 0 && this_ret > 0 && + if (!sr->retry && kmsg->msg.msg_inq > 1 && this_ret > 0 && !iov_iter_count(&kmsg->msg.msg_iter)) { req->cqe.flags = cflags & ~CQE_F_MASK; sr->len = kmsg->msg.msg_inq; @@ -1077,7 +1077,7 @@ static int io_recv_buf_select(struct io_ arg.mode |= KBUF_MODE_FREE; }
- if (kmsg->msg.msg_inq > 0) + if (kmsg->msg.msg_inq > 1) arg.max_len = min_not_zero(sr->len, kmsg->msg.msg_inq);
ret = io_buffers_peek(req, &arg);