Hi,

Can you queue this up for 5.4 as well? Thanks!

-------- Forwarded Message -------- Subject: [PATCH] fs/io_uring.c: Fix uninitialized variable is referenced in io_submit_sqe Date: Wed, 12 Aug 2020 23:56:44 -0700 From: Liu Yong pkfxxxing@gmail.com To: Jens Axboe axboe@kernel.dk CC: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org

the commit <a4d61e66ee4a> ("<io_uring: prevent re-read of sqe->opcode>") caused another vulnerability. After io_get_req(), the sqe_submit struct in req is not initialized, but the following code defaults that req->submit.opcode is available.

Signed-off-by: Liu Yong pkfxxxing@gmail.com --- fs/io_uring.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/fs/io_uring.c b/fs/io_uring.c index be3d595a607f..c1aaee061dae 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2559,6 +2559,7 @@ static void io_submit_sqe(struct io_ring_ctx *ctx, struct sqe_submit *s, goto err; }

+ memcpy(&req->submit, s, sizeof(*s)); ret = io_req_set_file(ctx, s, state, req); if (unlikely(ret)) { err_req: