[patch 023/108] x25: Fix sleep from timer on socket destroy.

Greg KH
2009-07-01T00:53:16Z

[-- Attachment #1: x25-fix-sleep-from-timer-on-socket-destroy.patch --]
[-- Type: text/plain, Size: 2752 bytes --]

2.6.30-stable review patch. If anyone has any objections, please let us know.

------------------

From: David S. Miller <davem@davemloft.net>

[ Upstream commit 14ebaf81e13ce66bff275380b246796fd16cbfa1 ]

If socket destuction gets delayed to a timer, we try to
lock_sock() from that timer which won't work.

Use bh_lock_sock() in that case.

Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
include/net/x25.h | 2 +-
net/x25/af_x25.c | 23 ++++++++++++++++++-----
net/x25/x25_timer.c | 2 +-
3 files changed, 20 insertions(+), 7 deletions(-)

--- a/include/net/x25.h
+++ b/include/net/x25.h
@@ -187,7 +187,7 @@ extern int x25_addr_ntoa(unsigned char
extern int x25_addr_aton(unsigned char *, struct x25_address *,
struct x25_address *);
extern struct sock *x25_find_socket(unsigned int, struct x25_neigh *);
-extern void x25_destroy_socket(struct sock *);
+extern void x25_destroy_socket_from_timer(struct sock *);
extern int x25_rx_call_request(struct sk_buff *, struct x25_neigh *, unsigned int);
extern void x25_kill_by_neigh(struct x25_neigh *);

--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -332,14 +332,14 @@ static unsigned int x25_new_lci(struct x
/*
* Deferred destroy.
*/
-void x25_destroy_socket(struct sock *);
+static void __x25_destroy_socket(struct sock *);

/*
* handler for deferred kills.
*/
static void x25_destroy_timer(unsigned long data)
{
- x25_destroy_socket((struct sock *)data);
+ x25_destroy_socket_from_timer((struct sock *)data);
}

/*
@@ -349,12 +349,10 @@ static void x25_destroy_timer(unsigned l
* will touch it and we are (fairly 8-) ) safe.
* Not static as it's used by the timer
*/
-void x25_destroy_socket(struct sock *sk)
+static void __x25_destroy_socket(struct sock *sk)
{
struct sk_buff *skb;

- sock_hold(sk);
- lock_sock(sk);
x25_stop_heartbeat(sk);
x25_stop_timer(sk);

@@ -385,7 +383,22 @@ void x25_destroy_socket(struct sock *sk)
/* drop last reference so sock_put will free */
__sock_put(sk);
}
+}

+void x25_destroy_socket_from_timer(struct sock *sk)
+{
+ sock_hold(sk);
+ bh_lock_sock(sk);
+ __x25_destroy_socket(sk);
+ bh_unlock_sock(sk);
+ sock_put(sk);
+}
+
+static void x25_destroy_socket(struct sock *sk)
+{
+ sock_hold(sk);
+ lock_sock(sk);
+ __x25_destroy_socket(sk);
release_sock(sk);
sock_put(sk);
}
--- a/net/x25/x25_timer.c
+++ b/net/x25/x25_timer.c
@@ -113,7 +113,7 @@ static void x25_heartbeat_expiry(unsigne
(sk->sk_state == TCP_LISTEN &&
sock_flag(sk, SOCK_DEAD))) {
bh_unlock_sock(sk);
- x25_destroy_socket(sk);
+ x25_destroy_socket_from_timer(sk);
return;
}
break;