From: Jiri Olsa Date: Thu, 5 Sep 2024 11:51:21 +0000 (+0300) Subject: bpf: Fix uprobe multi pid filter check X-Git-Tag: v6.12-rc1~112^2~41^2~3 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=900f362e2062e4a23a53bf89fd3b248cd021f5af;p=thirdparty%2Flinux.git bpf: Fix uprobe multi pid filter check Uprobe multi link does its own process (thread leader) filtering before running the bpf program by comparing task's vm pointers. But as Oleg pointed out there can be processes sharing the vm (CLONE_VM), so we can't just compare task->vm pointers, but instead we need to use same_thread_group call. Suggested-by: Oleg Nesterov Signed-off-by: Jiri Olsa Signed-off-by: Andrii Nakryiko Acked-by: Oleg Nesterov Link: https://lore.kernel.org/bpf/20240905115124.1503998-2-jolsa@kernel.org --- diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index b69a39316c0ce..98e395f1baae2 100644 --- 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; if (sleepable)