From: Hyunwoo Kim <imv4bel@gmail.com>
[ Upstream commit 598dbba9919c5e36c54fe1709b557d64120cb94b ]
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 <imv4bel@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Jianqiang kang <jianqkang@sina.cn>
---
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 d98648bcc1a8..d0ef74c45914 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -311,7 +311,7 @@ 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)
@@ -320,11 +320,15 @@ 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);
}
--
2.34.1