io_uring: restrict IORING_SETUP_SQPOLL to root

This options spawns a kernel side thread that will poll for submissions
(and completions, if IORING_SETUP_IOPOLL is set). As this allows a user
to potentially use more cycles outside of the normal hierarchy,
restrict the use of this feature to root.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2019-04-08 10:51:01 -06:00
parent 704236672e
commit 3ec482d15c

View file

@ -2245,6 +2245,10 @@ static int io_sq_offload_start(struct io_ring_ctx *ctx,
goto err;
if (ctx->flags & IORING_SETUP_SQPOLL) {
ret = -EPERM;
if (!capable(CAP_SYS_ADMIN))
goto err;
if (p->flags & IORING_SETUP_SQ_AFF) {
int cpu;