[PATCH 4.9 177/240] Bluetooth: initialize skb_queue_head at l2cap_chan_create()

Greg Kroah-Hartman
2021-05-20T11:19:27Z

From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>

[ Upstream commit be8597239379f0f53c9710dd6ab551bbf535bec6 ]

syzbot is hitting "INFO: trying to register non-static key." message [1],
for "struct l2cap_chan"->tx_q.lock spinlock is not yet initialized when
l2cap_chan_del() is called due to e.g. timeout.

Since "struct l2cap_chan"->lock mutex is initialized at l2cap_chan_create()
immediately after "struct l2cap_chan" is allocated using kzalloc(), let's
as well initialize "struct l2cap_chan"->{tx_q,srej_q}.lock spinlocks there.

[1] https://syzkaller.appspot.com/bug?extid=fadfba6a911f6bf71842

Reported-and-tested-by: syzbot <syzbot+fadfba6a911f6bf71842@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/bluetooth/l2cap_core.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index d586caaa3af4..204b6ebd2a24 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -445,6 +445,8 @@ struct l2cap_chan *l2cap_chan_create(void)
if (!chan)
return NULL;

+ skb_queue_head_init(&chan->tx_q);
+ skb_queue_head_init(&chan->srej_q);
mutex_init(&chan->lock);

/* Set default lock nesting level */
--
2.30.2