From: Daniele Albano d.albano@gmail.com
mainline inclusion from mainline-5.8-rc7 commit 61710e437f2807e26a3402543bdbb7217a9c8620 category: feature bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27 CVE: NA ---------------------------
We currently filter these for timeout_remove/async_cancel/files_update, but we only should be filtering for fixed file and buffer select. This also causes a second read of sqe->flags, which isn't needed.
Just check req->flags for the relevant bits. This then allows these commands to be used in links, for example, like everything else.
Signed-off-by: Daniele Albano d.albano@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: yangerkun yangerkun@huawei.com Reviewed-by: zhangyi (F) yi.zhang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com --- fs/io_uring.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c index 93a4d6a3ad57..3c86c4acbf86 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -4705,7 +4705,9 @@ static int io_timeout_remove_prep(struct io_kiocb *req, { if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; - if (sqe->flags || sqe->ioprio || sqe->buf_index || sqe->len) + if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT))) + return -EINVAL; + if (sqe->ioprio || sqe->buf_index || sqe->len) return -EINVAL;
req->timeout.addr = READ_ONCE(sqe->addr); @@ -4883,8 +4885,9 @@ static int io_async_cancel_prep(struct io_kiocb *req, { if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; - if (sqe->flags || sqe->ioprio || sqe->off || sqe->len || - sqe->cancel_flags) + if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT))) + return -EINVAL; + if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags) return -EINVAL;
req->cancel.addr = READ_ONCE(sqe->addr); @@ -4902,7 +4905,9 @@ static int io_async_cancel(struct io_kiocb *req) static int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { - if (sqe->flags || sqe->ioprio || sqe->rw_flags) + if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT))) + return -EINVAL; + if (sqe->ioprio || sqe->rw_flags) return -EINVAL;
req->files_update.offset = READ_ONCE(sqe->off);