diff options
| author | Dean Jenkins <Dean_Jenkins@mentor.com> | 2015-06-23 17:59:32 +0100 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2015-07-23 17:10:50 +0200 |
| commit | 2baea85dec1aebe0b100d4836dee8bcf29a51e94 (patch) | |
| tree | 4e64ae9832fb263dd317b89e424456a98838ff56 /net/bluetooth/l2cap_sock.c | |
| parent | d10270ce941ee89afd74076ea3ed8dbef8a0ff25 (diff) | |
| download | lwn-2baea85dec1aebe0b100d4836dee8bcf29a51e94.tar.gz lwn-2baea85dec1aebe0b100d4836dee8bcf29a51e94.zip | |
Bluetooth: L2CAP ERTM shutdown protect sk and chan
During execution of l2cap_sock_shutdown() which might
sleep, the sk and chan structures can be in an unlocked
condition which potentially allows the structures to be
freed by other running threads. Therefore, there is a
possibility of a malfunction or memory reuse after being
freed.
Keep the sk and chan structures alive during the
execution of l2cap_sock_shutdown() by using their
respective hold and put functions. This allows the structures
to be freeable at the end of l2cap_sock_shutdown().
Signed-off-by: Kautuk Consul <Kautuk_Consul@mentor.com>
Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Diffstat (limited to 'net/bluetooth/l2cap_sock.c')
| -rw-r--r-- | net/bluetooth/l2cap_sock.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c index 244287706f91..3794c2386c21 100644 --- a/net/bluetooth/l2cap_sock.c +++ b/net/bluetooth/l2cap_sock.c @@ -1098,7 +1098,12 @@ static int l2cap_sock_shutdown(struct socket *sock, int how) if (!sk) return 0; + /* prevent sk structure from being freed whilst unlocked */ + sock_hold(sk); + chan = l2cap_pi(sk)->chan; + /* prevent chan structure from being freed whilst unlocked */ + l2cap_chan_hold(chan); conn = chan->conn; BT_DBG("chan %p state %s", chan, state_to_string(chan->state)); @@ -1134,6 +1139,9 @@ static int l2cap_sock_shutdown(struct socket *sock, int how) if (conn) mutex_unlock(&conn->chan_lock); + l2cap_chan_put(chan); + sock_put(sk); + return err; } |