From 233b210a678bddf8b49b02a070074a52b87e6d43 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Mon, 10 Feb 2025 17:27:54 +0000 Subject: [PATCH] io_uring: fix multishots with selected buffers [ upstream commit d63b0e8a628e62ca85a0f7915230186bb92f8bb4 ] We do io_kbuf_recycle() when arming a poll but every iteration of a multishot can grab more buffers, which is why we need to flush the kbuf ring state before continuing with waiting. Cc: stable@vger.kernel.org Fixes: b3fdea6ecb55c ("io_uring: multishot recv") Reported-by: Muhammad Ramdhan Reported-by: Bing-Jhong Billy Jheng Reported-by: Jacob Soo Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/1bfc9990fe435f1fc6152ca9efeba5eb3e68339c.1738025570.git.asml.silence@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- io_uring/poll.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/io_uring/poll.c b/io_uring/poll.c index 428f84ed1021..bbdc9a7624a1 100644 --- a/io_uring/poll.c +++ b/io_uring/poll.c @@ -307,6 +307,8 @@ static int io_poll_check_events(struct io_kiocb *req, bool *locked) } } else { int ret = io_poll_issue(req, locked); + io_kbuf_recycle(req, 0); + if (ret == IOU_STOP_MULTISHOT) return IOU_POLL_REMOVE_POLL_USE_RES; if (ret < 0)