From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 17 Nov 2009 14:45:04 +0000 (-0800)
Subject: vlan: Fix register_vlan_dev() error path
X-Git-Tag: v2.6.31.9~35
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a5ad94d1e45df0cc29918fb5309ef85b99fc58c5;p=thirdparty%2Fkernel%2Fstable.git

vlan: Fix register_vlan_dev() error path

[ Upstream commit 6b863d1d3239eff0f45c2e6e672f5b56db828db0 ]

In case register_netdevice() returns an error, and a new vlan_group
was allocated and inserted in vlan_group_hash[] we call
vlan_group_free() without deleting group from hash table. Future
lookups can give infinite loops or crashes.

We must delete the vlan_group using RCU safe procedure.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
index fe649081fbdcc..db09b94663542 100644
--- a/net/8021q/vlan.c
+++ b/net/8021q/vlan.c
@@ -287,8 +287,11 @@ out_uninit_applicant:
 	if (ngrp)
 		vlan_gvrp_uninit_applicant(real_dev);
 out_free_group:
-	if (ngrp)
-		vlan_group_free(ngrp);
+	if (ngrp) {
+		hlist_del_rcu(&ngrp->hlist);
+		/* Free the group, after all cpu's are done. */
+		call_rcu(&ngrp->rcu, vlan_rcu_free);
+	}
 	return err;
 }