[patch 09/26] Fix netlink timeouts.

From: Greg Kroah-Hartman
Date: Mon Nov 19 2007 - 13:24:44 EST


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

------------------
From: Patrick McHardy <kaber@xxxxxxxxx>

[NETLINK]: Fix unicast timeouts

[ Upstream commit: c3d8d1e30cace31fed6186a4b8c6b1401836d89c ]

Commit ed6dcf4a in the history.git tree broke netlink_unicast timeouts
by moving the schedule_timeout() call to a new function that doesn't
propagate the remaining timeout back to the caller. This means on each
retry we start with the full timeout again.

ipc/mqueue.c seems to actually want to wait indefinitely so this
behaviour is retained.

Signed-off-by: Patrick McHardy <kaber@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
include/linux/netlink.h | 2 +-
ipc/mqueue.c | 6 ++++--
net/netlink/af_netlink.c | 10 +++++-----
3 files changed, 10 insertions(+), 8 deletions(-)

--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h
@@ -173,7 +173,7 @@ extern int netlink_unregister_notifier(s
/* finegrained unicast helpers: */
struct sock *netlink_getsockbyfilp(struct file *filp);
int netlink_attachskb(struct sock *sk, struct sk_buff *skb, int nonblock,
- long timeo, struct sock *ssk);
+ long *timeo, struct sock *ssk);
void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
int netlink_sendskb(struct sock *sk, struct sk_buff *skb, int protocol);

--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -1014,6 +1014,8 @@ asmlinkage long sys_mq_notify(mqd_t mqde
return -EINVAL;
}
if (notification.sigev_notify == SIGEV_THREAD) {
+ long timeo;
+
/* create the notify skb */
nc = alloc_skb(NOTIFY_COOKIE_LEN, GFP_KERNEL);
ret = -ENOMEM;
@@ -1042,8 +1044,8 @@ retry:
goto out;
}

- ret = netlink_attachskb(sock, nc, 0,
- MAX_SCHEDULE_TIMEOUT, NULL);
+ timeo = MAX_SCHEDULE_TIMEOUT;
+ ret = netlink_attachskb(sock, nc, 0, &timeo, NULL);
if (ret == 1)
goto retry;
if (ret) {
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -732,7 +732,7 @@ struct sock *netlink_getsockbyfilp(struc
* 1: repeat lookup - reference dropped while waiting for socket memory.
*/
int netlink_attachskb(struct sock *sk, struct sk_buff *skb, int nonblock,
- long timeo, struct sock *ssk)
+ long *timeo, struct sock *ssk)
{
struct netlink_sock *nlk;

@@ -741,7 +741,7 @@ int netlink_attachskb(struct sock *sk, s
if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
test_bit(0, &nlk->state)) {
DECLARE_WAITQUEUE(wait, current);
- if (!timeo) {
+ if (!*timeo) {
if (!ssk || nlk_sk(ssk)->pid == 0)
netlink_overrun(sk);
sock_put(sk);
@@ -755,7 +755,7 @@ int netlink_attachskb(struct sock *sk, s
if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
test_bit(0, &nlk->state)) &&
!sock_flag(sk, SOCK_DEAD))
- timeo = schedule_timeout(timeo);
+ *timeo = schedule_timeout(*timeo);

__set_current_state(TASK_RUNNING);
remove_wait_queue(&nlk->wait, &wait);
@@ -763,7 +763,7 @@ int netlink_attachskb(struct sock *sk, s

if (signal_pending(current)) {
kfree_skb(skb);
- return sock_intr_errno(timeo);
+ return sock_intr_errno(*timeo);
}
return 1;
}
@@ -827,7 +827,7 @@ retry:
kfree_skb(skb);
return PTR_ERR(sk);
}
- err = netlink_attachskb(sk, skb, nonblock, timeo, ssk);
+ err = netlink_attachskb(sk, skb, nonblock, &timeo, ssk);
if (err == 1)
goto retry;
if (err)

--
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/