The patch below does not apply to the 5.17-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 7179c3ce3dbff646c55f7cd664a895f462f049e5 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov asml.silence@gmail.com Date: Wed, 13 Apr 2022 16:10:35 +0100 Subject: [PATCH] io_uring: fix poll error reporting

We should not return an error code in req->result in io_poll_check_events(), because it may get mangled and returned as success. Just return the error code directly, the callers will fail the request or proceed accordingly.

Fixes: 6bf9c47a3989 ("io_uring: defer file assignment") Signed-off-by: Pavel Begunkov asml.silence@gmail.com Link: https://lore.kernel.org/r/5f03514ee33324dc811fb93df84aee0f695fb044.164986251... Signed-off-by: Jens Axboe axboe@kernel.dk

diff --git a/fs/io_uring.c b/fs/io_uring.c index d06f1952fdfa..ab674a0d269b 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -5861,9 +5861,8 @@ static int io_poll_check_events(struct io_kiocb *req, bool locked) unsigned flags = locked ? 0 : IO_URING_F_UNLOCKED;

if (unlikely(!io_assign_file(req, flags))) - req->result = -EBADF; - else - req->result = vfs_poll(req->file, &pt) & req->apoll_events; + return -EBADF; + req->result = vfs_poll(req->file, &pt) & req->apoll_events; }

/* multishot, just fill an CQE and proceed */