On Mon, May 19, 2025 at 10:51 PM Xuewen Yan <[email protected]> wrote: > > From: Di Shen <[email protected]> > > This reverts commit 4a8f635a60540888dab3804992e86410360339c8. > > Althought get_pid_task() internally already calls rcu_read_lock() and > rcu_read_unlock(), the find_vpid() was not. > > The documentation for find_vpid() clearly states: > > "Must be called with the tasklist_lock or rcu_read_lock() held." > > Add proper rcu_read_lock/unlock() to protect the find_vpid(). > > Reported-by: Xuewen Yan <[email protected]> > Signed-off-by: Di Shen <[email protected]> > --- > kernel/trace/bpf_trace.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c > index 187dc37d61d4..0c4b6af10601 100644 > --- a/kernel/trace/bpf_trace.c > +++ b/kernel/trace/bpf_trace.c > @@ -3417,7 +3417,9 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr > *attr, struct bpf_prog *pr > } > > if (pid) { > + rcu_read_lock(); > task = get_pid_task(find_vpid(pid), PIDTYPE_TGID); > + rcu_read_unlock(); > if (!task) { > err = -ESRCH; > goto error_path_put;
hmm. indeed. Jiri ?
