Re: [PATCHv2 bpf-next 1/4] bpf: Fix uprobe multi pid filter check

[Oleg Nesterov]

On 09/05, Jiri Olsa wrote:
>
> --- a/kernel/trace/bpf_trace.c
> +++ b/kernel/trace/bpf_trace.c
> @@ -3207,7 +3207,7 @@ static int uprobe_prog_run(struct bpf_uprobe *uprobe,
>  	struct bpf_run_ctx *old_run_ctx;
>  	int err = 0;
>
> -	if (link->task && current->mm != link->task->mm)
> +	if (link->task && !same_thread_group(current, link->task))
>  		return 0;

plus the current check can return false negative if link->task->mm == NULL

Acked-by: Oleg Nesterov <oleg@xxxxxxxxxx>