uprobes: Fix incorrect lockdep condition in filter_chain()

The list_for_each_entry_rcu() in filter_chain() uses
rcu_read_lock_trace_held() as the lockdep condition, but the function
holds consumer_rwsem, not the RCU trace lock.

This gives me the following output when running with some locking debug
option enabled:

  kernel/events/uprobes.c:1141 RCU-list traversed in non-reader section!!
    filter_chain
    register_for_each_vma
    uprobe_unregister_nosync
    __probe_event_disable

Remove the incorrect lockdep condition since the rwsem provides
sufficient protection for the list traversal.

Fixes: cc01bd044e6a ("uprobes: travers uprobe's consumer list locklessly under SRCU protection")
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260128-uprobe_rcu-v2-1-994ea6d32730@debian.org

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index dfbce021fb0271a30120ed9ca2d836ea3891b4cd..424ef2235b07e6e464e877993cf16c8559f5e3f9 100644 (file)
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1138,7 +1138,7 @@ static bool filter_chain(struct uprobe *uprobe, struct mm_struct *mm)
        bool ret = false;
 
        down_read(&uprobe->consumer_rwsem);
-       list_for_each_entry_rcu(uc, &uprobe->consumers, cons_node, rcu_read_lock_trace_held()) {
+       list_for_each_entry(uc, &uprobe->consumers, cons_node) {
                ret = consumer_filter(uc, mm);
                if (ret)
                        break;