diff options
| author | Ying Hsu <yinghsu@chromium.org> | 2022-03-26 07:09:28 +0000 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2022-05-13 13:05:48 +0200 |
| commit | 7aa1e7d15f8a5b65f67bacb100d8fc033b21efa2 (patch) | |
| tree | 484fbddc4f03e361a55c9bcb456ebaff2524f833 | |
| parent | 789f6b8ac3b15bca09b69d5699cad0bf6e2103aa (diff) | |
Bluetooth: fix dangling sco_conn and use-after-free in sco_sock_timeout
Connecting the same socket twice consecutively in sco_sock_connect()
could lead to a race condition where two sco_conn objects are created
but only one is associated with the socket. If the socket is closed
before the SCO connection is established, the timer associated with the
dangling sco_conn object won't be canceled. As the sock object is being
freed, the use-after-free problem happens when the timer callback
function sco_sock_timeout() accesses the socket. Here's the call trace:
dump_stack+0x107/0x163
? refcount_inc+0x1c/
print_address_description.constprop.0+0x1c/0x47e
? refcount_inc+0x1c/0x7b
kasan_report+0x13a/0x173
? refcount_inc+0x1c/0x7b
check_memory_region+0x132/0x139
refcount_inc+0x1c/0x7b
sco_sock_timeout+0xb2/0x1ba
process_one_work+0x739/0xbd1
? cancel_delayed_work+0x13f/0x13f
? __raw_spin_lock_init+0xf0/0xf0
? to_kthread+0x59/0x85
worker_thread+0x593/0x70e
kthread+0x346/0x35a
? drain_workqueue+0x31a/0x31a
? kthread_bind+0x4b/0x4b
ret_from_fork+0x1f/0x30
Link: https://syzkaller.appspot.com/bug?extid=2bef95d3ab4daa10155b
Reported-by: syzbot+2bef95d3ab4daa10155b@syzkaller.appspotmail.com
Fixes: e1dee2c1de2b ("Bluetooth: fix repeated calls to sco_sock_kill")
Signed-off-by: Ying Hsu <yinghsu@chromium.org>
Reviewed-by: Joseph Hwang <josephsih@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
| -rw-r--r-- | net/bluetooth/sco.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c index 8eabf41b2993..380c63194736 100644 --- a/net/bluetooth/sco.c +++ b/net/bluetooth/sco.c @@ -574,19 +574,24 @@ static int sco_sock_connect(struct socket *sock, struct sockaddr *addr, int alen addr->sa_family != AF_BLUETOOTH) return -EINVAL; - if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) - return -EBADFD; + lock_sock(sk); + if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) { + err = -EBADFD; + goto done; + } - if (sk->sk_type != SOCK_SEQPACKET) - return -EINVAL; + if (sk->sk_type != SOCK_SEQPACKET) { + err = -EINVAL; + goto done; + } hdev = hci_get_route(&sa->sco_bdaddr, &sco_pi(sk)->src, BDADDR_BREDR); - if (!hdev) - return -EHOSTUNREACH; + if (!hdev) { + err = -EHOSTUNREACH; + goto done; + } hci_dev_lock(hdev); - lock_sock(sk); - /* Set destination address and psm */ bacpy(&sco_pi(sk)->dst, &sa->sco_bdaddr); |