| Message ID | f9975604-6a65-4bcc-b532-15fcaa6da0e5@stanley.mountain |
|---|---|
| State | New |
| Headers | show |
| Series | [next] Bluetooth: L2CAP: Fix NULL dereference in l2cap_recv_acldata() | expand |
On Wed, Feb 12, 2025 at 05:23:42PM -0500, Luiz Augusto von Dentz wrote: > Hi Dan, > > On Wed, Feb 12, 2025 at 11:40 AM Dan Carpenter <dan.carpenter@linaro.org> wrote: > > > > 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@linaro.org> > > --- > > 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 > > I went ahead and fixed this in place since it has not been sent to net > yet, I did add your Signed-off-by though. Thanks. regards, dan carpenter
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);
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@linaro.org> --- net/bluetooth/l2cap_core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)