Hi Jens,
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index 6c62a3c95c1a..9a732b3b39fa 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
> @@ -269,6 +269,7 @@ struct io_sq_data {
> unsigned sq_thread_idle;
> int sq_cpu;
> pid_t task_pid;
> + pid_t task_tgid;
>
> unsigned long state;
> struct completion startup;
> @@ -7081,6 +7082,10 @@ static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
> fdput(f);
> return ERR_PTR(-EINVAL);
> }
> + if (sqd->task_tgid != current->tgid) {
> + fdput(f);
> + return ERR_PTR(-EPERM);
> + }
>
> refcount_inc(&sqd->refs);
> fdput(f);
> @@ -7091,8 +7096,14 @@ static struct io_sq_data *io_get_sq_data(struct io_uring_params *p)
> {
> struct io_sq_data *sqd;
>
> - if (p->flags & IORING_SETUP_ATTACH_WQ)
> - return io_attach_sq_data(p);
> + if (p->flags & IORING_SETUP_ATTACH_WQ) {
> + sqd = io_attach_sq_data(p);
> + if (!IS_ERR(sqd))
> + return sqd;
> + /* fall through for EPERM case, setup new sqd/task */
> + if (PTR_ERR(sqd) != -EPERM)
> + return sqd;
> + }
>
> sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
> if (!sqd)
> @@ -7793,6 +7804,7 @@ static int io_sq_offload_create(struct io_ring_ctx *ctx,
> }
>
> sqd->task_pid = current->pid;
> + sqd->task_tgid = current->tgid;
> tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE);
> if (IS_ERR(tsk)) {
> ret = PTR_ERR(tsk);
>
Ok, that looks nice and simple, thanks!
metze
