summaryrefslogtreecommitdiff
path: root/net/bluetooth/af_bluetooth.c
diff options
context:
space:
mode:
authorLuiz Augusto von Dentz <luiz.von.dentz@intel.com>2024-03-01 12:58:11 -0500
committerLuiz Augusto von Dentz <luiz.von.dentz@intel.com>2024-03-06 17:26:25 -0500
commitf7b94bdc1ec107c92262716b073b3e816d4784fb (patch)
tree7ae770f2430844d22ca97738d43e9707f86dc444 /net/bluetooth/af_bluetooth.c
parent0f0639b4d6f649338ce29c62da3ec0787fa08cd1 (diff)
Bluetooth: af_bluetooth: Fix deadlock
Attemting to do sock_lock on .recvmsg may cause a deadlock as shown bellow, so instead of using sock_sock this uses sk_receive_queue.lock on bt_sock_ioctl to avoid the UAF: INFO: task kworker/u9:1:121 blocked for more than 30 seconds. Not tainted 6.7.6-lemon #183 Workqueue: hci0 hci_rx_work Call Trace: <TASK> __schedule+0x37d/0xa00 schedule+0x32/0xe0 __lock_sock+0x68/0xa0 ? __pfx_autoremove_wake_function+0x10/0x10 lock_sock_nested+0x43/0x50 l2cap_sock_recv_cb+0x21/0xa0 l2cap_recv_frame+0x55b/0x30a0 ? psi_task_switch+0xeb/0x270 ? finish_task_switch.isra.0+0x93/0x2a0 hci_rx_work+0x33a/0x3f0 process_one_work+0x13a/0x2f0 worker_thread+0x2f0/0x410 ? __pfx_worker_thread+0x10/0x10 kthread+0xe0/0x110 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2c/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK> Fixes: 2e07e8348ea4 ("Bluetooth: af_bluetooth: Fix Use-After-Free in bt_sock_recvmsg") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Diffstat (limited to 'net/bluetooth/af_bluetooth.c')
-rw-r--r--net/bluetooth/af_bluetooth.c10
1 files changed, 3 insertions, 7 deletions
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index b93464ac3517..67604ccec2f4 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -309,14 +309,11 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
if (flags & MSG_OOB)
return -EOPNOTSUPP;
- lock_sock(sk);
-
skb = skb_recv_datagram(sk, flags, &err);
if (!skb) {
if (sk->sk_shutdown & RCV_SHUTDOWN)
err = 0;
- release_sock(sk);
return err;
}
@@ -346,8 +343,6 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
skb_free_datagram(sk, skb);
- release_sock(sk);
-
if (flags & MSG_TRUNC)
copied = skblen;
@@ -570,10 +565,11 @@ int bt_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
if (sk->sk_state == BT_LISTEN)
return -EINVAL;
- lock_sock(sk);
+ spin_lock(&sk->sk_receive_queue.lock);
skb = skb_peek(&sk->sk_receive_queue);
amount = skb ? skb->len : 0;
- release_sock(sk);
+ spin_unlock(&sk->sk_receive_queue.lock);
+
err = put_user(amount, (int __user *)arg);
break;