From: Budimir Markovic <markovicbudimir@gmail.com>

Date: Wed, 15 Mar 2023 00:29:01 -0700

Subject: [PATCH] perf: Fix check before add_event_to_groups() in

 perf_group_detach()

References: bsc#1012628

Patch-mainline: 6.2.8

Git-commit: fd0815f632c24878e325821943edccc7fde947a2

commit fd0815f632c24878e325821943edccc7fde947a2 upstream.

Events should only be added to a groups rb tree if they have not been

removed from their context by list_del_event(). Since remove_on_exec

made it possible to call list_del_event() on individual events before

they are detached from their group, perf_group_detach() should check each

sibling's attach_state before calling add_event_to_groups() on it.

Fixes: 2e498d0a74e5 ("perf: Add support for event removal on exec")

Signed-off-by: Budimir Markovic <markovicbudimir@gmail.com>

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Link: https://lkml.kernel.org/r/ZBFzvQV9tEqoHEtH@gentoo

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Jiri Slaby <jslaby@suse.cz>

---

 kernel/events/core.c | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c

index c4be13e5..8ae8a505 100644

--- a/kernel/events/core.c

+++ b/kernel/events/core.c

@@ -2163,7 +2163,7 @@ static void perf_group_detach(struct perf_event *event)

 		/* Inherit group flags from the previous leader */

 		sibling->group_caps = event->group_caps;

-		if (!RB_EMPTY_NODE(&event->group_node)) {

+		if (sibling->attach_state & PERF_ATTACH_CONTEXT) {

 			add_event_to_groups(sibling, event->ctx);

 			if (sibling->state == PERF_EVENT_STATE_ACTIVE)

-- 

2.35.3