Commit 1498b3f1 authored Jul 09, 2007 by Satyam Sharma Committed by David S. Miller Jul 10, 2007

[NETPOLL]: Fix a leak-n-bug in netpoll_cleanup()



93ec2c72 applied excessive duct tape to
the netpoll beast's netpoll_cleanup(), thus substituting one leak with
another, and opening up a little buglet :-)

net_device->npinfo (netpoll_info) is a shared and refcounted object and
cannot simply be set NULL the first time netpoll_cleanup() is called.
Otherwise, further netpoll_cleanup()'s see np->dev->npinfo == NULL and
become no-ops, thus leaking. And it's a bug too: the first call to
netpoll_cleanup() would thus (annoyingly) "disable" other (still alive)
netpolls too. Maybe nobody noticed this because netconsole (only user
of netpoll) never supported multiple netpoll objects earlier.

This is a trivial and obvious one-line fixlet.

Signed-off-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 5f1de3ec

net/core/netpoll.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -783,7 +783,6 @@ void netpoll_cleanup(struct netpoll *np)
		spin_unlock_irqrestore(&npinfo->rx_lock, flags);
		}

		np->dev->npinfo = NULL;
		if (atomic_dec_and_test(&npinfo->refcnt)) {
		skb_queue_purge(&npinfo->arp_tx);
		skb_queue_purge(&npinfo->txq);
		@@ -796,6 +795,7 @@ void netpoll_cleanup(struct netpoll *np)
		kfree_skb(skb);
		}
		kfree(npinfo);
		np->dev->npinfo = NULL;
		}
		}