[PATCH next] Bluetooth: L2CAP: Fix NULL dereference in l2cap_recv_acldata()

From: Dan Carpenter
Date: Wed Feb 12 2025 - 11:41:38 EST


The "conn" pointer is NULL so this "goto drop;" will lead to a NULL
dereference when we call mutex_unlock(&conn->lock). Free the skb and
return directly instead.

Fixes: dd6367916d2d ("Bluetooth: L2CAP: Fix corrupted list in hci_chan_del")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
net/bluetooth/l2cap_core.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 6cdc1dc3a7f9..fec11e576f31 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -7456,8 +7456,10 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)

hci_dev_unlock(hcon->hdev);

- if (!conn)
- goto drop;
+ if (!conn) {
+ kfree_skb(skb);
+ return;
+ }

BT_DBG("conn %p len %u flags 0x%x", conn, skb->len, flags);

--
2.47.2