Re: [syzbot] #syz test

[syzbot <syzbot+ff3aa851d46ab82953a3@syzkaller.appspotmail.com>]

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***

Subject: #syz test
Author: gshahrouzi@gmail.com

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 0bb21659e252..153ba622cfa0 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -14016,6 +14016,9 @@ inherit_event(struct perf_event *parent_event,
        if (IS_ERR(child_event))
                return child_event;

+       get_ctx(child_ctx);
+       child_event->ctx = child_ctx;
+
        pmu_ctx = find_get_pmu_context(child_event->pmu, child_ctx,
child_event);
        if (IS_ERR(pmu_ctx)) {
                free_event(child_event);
@@ -14037,8 +14040,6 @@ inherit_event(struct perf_event *parent_event,
                return NULL;
        }

-       get_ctx(child_ctx);
-
        /*
         * Make the child state follow the state of the parent event,
         * not its attr.disabled bit.  We hold the parent's mutex,
@@ -14059,7 +14060,6 @@ inherit_event(struct perf_event *parent_event,
                local64_set(&hwc->period_left, sample_period);
        }

-       child_event->ctx = child_ctx;
        child_event->overflow_handler = parent_event->overflow_handler;
        child_event->overflow_handler_context
                = parent_event->overflow_handler_context;
-- 
2.43.0