From 598dbba9919c5e36c54fe1709b557d64120cb94b Mon Sep 17 00:00:00 2001 From: Hyunwoo Kim Date: Fri, 13 Mar 2026 05:26:16 +0900 Subject: Bluetooth: SCO: Fix use-after-free in sco_recv_frame() due to missing sock_hold sco_recv_frame() reads conn->sk under sco_conn_lock() but immediately releases the lock without holding a reference to the socket. A concurrent close() can free the socket between the lock release and the subsequent sk->sk_state access, resulting in a use-after-free. Other functions in the same file (sco_sock_timeout(), sco_conn_del()) correctly use sco_sock_hold() to safely hold a reference under the lock. Fix by using sco_sock_hold() to take a reference before releasing the lock, and adding sock_put() on all exit paths. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Hyunwoo Kim Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/sco.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c index e7db50165879..584e059de20a 100644 --- a/net/bluetooth/sco.c +++ b/net/bluetooth/sco.c @@ -401,7 +401,7 @@ static void sco_recv_frame(struct sco_conn *conn, struct sk_buff *skb) struct sock *sk; sco_conn_lock(conn); - sk = conn->sk; + sk = sco_sock_hold(conn); sco_conn_unlock(conn); if (!sk) @@ -410,11 +410,15 @@ static void sco_recv_frame(struct sco_conn *conn, struct sk_buff *skb) BT_DBG("sk %p len %u", sk, skb->len); if (sk->sk_state != BT_CONNECTED) - goto drop; + goto drop_put; - if (!sock_queue_rcv_skb(sk, skb)) + if (!sock_queue_rcv_skb(sk, skb)) { + sock_put(sk); return; + } +drop_put: + sock_put(sk); drop: kfree_skb(skb); } -- cgit v1.2.3