From: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> [ Upstream commit 14d5511691e5290103bc480998bc322e68f139d4 ] If cec_notifier_cec_adap_unregister() is called before cec_unregister_adapter() then everything is OK (and this is the case today). But if it is the other way around, then cec_notifier_unregister() is called first, and that doesn't set n->cec_adap to NULL. So if e.g. cec_notifier_set_phys_addr() is called after cec_notifier_unregister() but before cec_unregister_adapter() then n->cec_adap points to an unregistered and likely deleted cec adapter. So just set n->cec_adap->notifier and n->cec_adap to NULL for rubustness. Eventually cec_notifier_unregister will disappear and this will be simplified substantially. Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/media/cec/cec-notifier.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/media/cec/cec-notifier.c b/drivers/media/cec/cec-notifier.c index 52a867bde15fd..4d82a5522072e 100644 --- a/drivers/media/cec/cec-notifier.c +++ b/drivers/media/cec/cec-notifier.c @@ -218,6 +218,8 @@ void cec_notifier_unregister(struct cec_notifier *n) mutex_lock(&n->lock); n->callback = NULL; + n->cec_adap->notifier = NULL; + n->cec_adap = NULL; mutex_unlock(&n->lock); cec_notifier_put(n); } -- 2.20.1
