[Bluetooth] Fix deadlock in the L2CAP layer
The Bluetooth L2CAP layer has 2 locks that are used in softirq context,
(one spinlock and one rwlock, where the softirq usage is readlock) but
where not all usages of the lock were _bh safe. The patch below corrects
this.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index fc1b54f..9d2d1d6 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -168,9 +168,9 @@
static inline void l2cap_chan_add(struct l2cap_conn *conn, struct sock *sk, struct sock *parent)
{
struct l2cap_chan_list *l = &conn->chan_list;
- write_lock(&l->lock);
+ write_lock_bh(&l->lock);
__l2cap_chan_add(conn, sk, parent);
- write_unlock(&l->lock);
+ write_unlock_bh(&l->lock);
}
static inline u8 l2cap_get_ident(struct l2cap_conn *conn)
@@ -183,14 +183,14 @@
* 200 - 254 are used by utilities like l2ping, etc.
*/
- spin_lock(&conn->lock);
+ spin_lock_bh(&conn->lock);
if (++conn->tx_ident > 128)
conn->tx_ident = 1;
id = conn->tx_ident;
- spin_unlock(&conn->lock);
+ spin_unlock_bh(&conn->lock);
return id;
}
@@ -1007,7 +1007,7 @@
{
struct sock *next = l2cap_pi(sk)->next_c, *prev = l2cap_pi(sk)->prev_c;
- write_lock(&l->lock);
+ write_lock_bh(&l->lock);
if (sk == l->head)
l->head = next;
@@ -1015,7 +1015,7 @@
l2cap_pi(next)->prev_c = prev;
if (prev)
l2cap_pi(prev)->next_c = next;
- write_unlock(&l->lock);
+ write_unlock_bh(&l->lock);
__sock_put(sk);
}
@@ -1425,11 +1425,11 @@
if (!sk)
goto response;
- write_lock(&list->lock);
+ write_lock_bh(&list->lock);
/* Check if we already have channel with that dcid */
if (__l2cap_get_chan_by_dcid(list, scid)) {
- write_unlock(&list->lock);
+ write_unlock_bh(&list->lock);
sock_set_flag(sk, SOCK_ZAPPED);
l2cap_sock_kill(sk);
goto response;
@@ -1467,7 +1467,7 @@
result = status = 0;
done:
- write_unlock(&list->lock);
+ write_unlock_bh(&list->lock);
response:
bh_unlock_sock(parent);
