io_uring: fix 0-iov read buffer select

commit dd20166236953c8cd14f4c668bf972af32f0c6be upstream.

Doing vectored buf-select read with 0 iovec passed is meaningless and
utterly broken, forbid it.

Cc: <stable@vger.kernel.org> # 5.7+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Pavel Begunkov 2020-12-19 03:15:43 +00:00 committed by Greg Kroah-Hartman
parent b1442adcd9
commit 72a016d42d

View File

@ -3048,9 +3048,7 @@ static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
iov[0].iov_len = kbuf->len;
return 0;
}
if (!req->rw.len)
return 0;
else if (req->rw.len > 1)
if (req->rw.len != 1)
return -EINVAL;
#ifdef CONFIG_COMPAT