Sockets and other non-regular files may actually expect short reads to happen, don't retry reads for them. Because non-reg files don't set FMODE_BUF_RASYNC and so it won't do second/retry do_read, we can filter out those cases after first do_read() attempt with ret>0.

Cc: stable@vger.kernel.org # 5.9+ Suggested-by: Jens Axboe axboe@kernel.dk Signed-off-by: Pavel Begunkov asml.silence@gmail.com ---

v2: essentially same, but a bit cleaner check placement and extended commit message

fs/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c index 5f6f1e48954e..18920f9785d2 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -3552,7 +3552,7 @@ static int io_read(struct io_kiocb *req, bool force_nonblock,

/* read it all, or we did blocking attempt. no retry. */ if (!iov_iter_count(iter) || !force_nonblock || - (req->file->f_flags & O_NONBLOCK)) + (req->file->f_flags & O_NONBLOCK) || !(req->flags & REQ_F_ISREG)) goto done;

io_size -= ret;