[PATCH 5.14 341/849] Bluetooth: fix init and cleanup of sco_conn.timeout_work

Greg Kroah-Hartman
2021-11-15T22:51:23Z

From: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>

[ Upstream commit 49d8a5606428ca0962d09050a5af81461ff90fbb ]

Before freeing struct sco_conn, all delayed timeout work should be
cancelled. Otherwise, sco_sock_timeout could potentially use the
sco_conn after it has been freed.

Additionally, sco_conn.timeout_work should be initialized when the
connection is allocated, not when the channel is added. This is
because an sco_conn can create channels with multiple sockets over its
lifetime, which happens if sockets are released but the connection
isn't deleted.

Fixes: ba316be1b6a0 ("Bluetooth: schedule SCO timeouts with delayed_work")
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/bluetooth/sco.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index 2766faf95c534..2e251ac89da58 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -134,6 +134,7 @@ static struct sco_conn *sco_conn_add(struct hci_conn *hcon)
return NULL;

spin_lock_init(&conn->lock);
+ INIT_DELAYED_WORK(&conn->timeout_work, sco_sock_timeout);

hcon->sco_data = conn;
conn->hcon = hcon;
@@ -197,11 +198,11 @@ static void sco_conn_del(struct hci_conn *hcon, int err)
sco_chan_del(sk, err);
bh_unlock_sock(sk);
sock_put(sk);
-
- /* Ensure no more work items will run before freeing conn. */
- cancel_delayed_work_sync(&conn->timeout_work);
}

+ /* Ensure no more work items will run before freeing conn. */
+ cancel_delayed_work_sync(&conn->timeout_work);
+
hcon->sco_data = NULL;
kfree(conn);
}
@@ -214,8 +215,6 @@ static void __sco_chan_add(struct sco_conn *conn, struct sock *sk,
sco_pi(sk)->conn = conn;
conn->sk = sk;

- INIT_DELAYED_WORK(&conn->timeout_work, sco_sock_timeout);
-
if (parent)
bt_accept_enqueue(parent, sk, true);
}
--
2.33.0