From 622ccdf107bcb49c4d8fb65512652566d4c8928a Mon Sep 17 00:00:00 2001
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Tue, 18 May 2010 15:56:06 -0700
Subject: [PATCH] ipv6: Never schedule DAD timer on dead address
This patch ensures that all places that schedule the DAD timer
look at the address state in a safe manner before scheduling the
timer. This ensures that we don't end up with pending timers
after deleting an address.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/ipv6/addrconf.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 7c769fa81d97..e1a698df5706 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2853,10 +2853,10 @@ static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags)
net_srandom(ifp->addr.s6_addr32[3]);
read_lock_bh(&idev->lock);
+ spin_lock(&ifp->lock);
if (ifp->state == INET6_IFADDR_STATE_DEAD)
goto out;
- spin_lock(&ifp->lock);
if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
idev->cnf.accept_dad < 1 ||
!(ifp->flags&IFA_F_TENTATIVE) ||
@@ -2890,8 +2890,8 @@ static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags)
ip6_ins_rt(ifp->rt);
addrconf_dad_kick(ifp);
- spin_unlock(&ifp->lock);
out:
+ spin_unlock(&ifp->lock);
read_unlock_bh(&idev->lock);
}
@@ -2911,6 +2911,12 @@ static void addrconf_dad_timer(unsigned long data)
}
spin_lock(&ifp->lock);
+ if (ifp->state == INET6_IFADDR_STATE_DEAD) {
+ spin_unlock(&ifp->lock);
+ read_unlock(&idev->lock);
+ goto out;
+ }
+
if (ifp->probes == 0) {
/*
* DAD was successful
--
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