From: Min Li <lm0963hack@xxxxxxxxx> [ Upstream commit 25e97f7b1866e6b8503be349eeea44bb52d661ce ] conn->chan_lock isn't acquired before l2cap_get_chan_by_scid, if l2cap_get_chan_by_scid returns NULL, then 'bad unlock balance' is triggered. Reported-by: syzbot+9519d6b5b79cf7787cf3@xxxxxxxxxxxxxxxxxxxxxxxxx Link: https://lore.kernel.org/all/000000000000894f5f05f95e9f4d@xxxxxxxxxx/ Signed-off-by: Min Li <lm0963hack@xxxxxxxxx> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/bluetooth/l2cap_core.c | 1 - 1 file changed, 1 deletion(-) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 1a68aad5737e1..94d40a20ab958 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -4392,7 +4392,6 @@ static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn, chan = l2cap_get_chan_by_scid(conn, scid); if (!chan) { - mutex_unlock(&conn->chan_lock); return 0; } -- 2.39.2