From: Jens Axboe <axboe@kernel.dk>
Date: Wed, 23 Jun 2021 15:07:45 +0000 (-0600)
Subject: io_uring: add IOPOLL and reserved field checks to IORING_OP_UNLINKAT
X-Git-Tag: v5.12.17~11
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3d62a74f2b90a51b873aa622ff768947eda99db1;p=thirdparty%2Fkernel%2Fstable.git

io_uring: add IOPOLL and reserved field checks to IORING_OP_UNLINKAT

commit 22634bc5620d29765e5199c7b230a372c7ddcda2 upstream.

We can't support IOPOLL with non-pollable request types, and we should
check for unused/reserved fields like we do for other request types.

Fixes: 14a1143b68ee ("io_uring: add support for IORING_OP_UNLINKAT")
Cc: stable@vger.kernel.org
Reported-by: Dmitry Kadashev <dkadashev@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/io_uring.c b/fs/io_uring.c
index bdf619bf4ae61..58ac04cca587f 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3548,6 +3548,10 @@ static int io_unlinkat_prep(struct io_kiocb *req,
 	struct io_unlink *un = &req->unlink;
 	const char __user *fname;
 
+	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
+	if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index)
+		return -EINVAL;
 	if (unlikely(req->flags & REQ_F_FIXED_FILE))
 		return -EBADF;