diff options
| author | Andrey Vagin <avagin@parallels.com> | 2008-07-08 15:13:31 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-07-08 15:13:31 -0700 |
| commit | b2238566401f01eb796e75750213c7b0fce396b2 (patch) | |
| tree | 01135bc75b5a212fe13e98ddc7721e9aae6584f0 /net | |
| parent | 07035fc1bbf931a06e47583cddd2cea2907ac0db (diff) | |
| download | lwn-b2238566401f01eb796e75750213c7b0fce396b2.tar.gz lwn-b2238566401f01eb796e75750213c7b0fce396b2.zip | |
ipv6: fix race between ipv6_del_addr and DAD timer
Consider the following scenario:
ipv6_del_addr(ifp)
ipv6_ifa_notify(RTM_DELADDR, ifp)
ip6_del_rt(ifp->rt)
after returning from the ipv6_ifa_notify and enabling BH-s
back, but *before* calling the addrconf_del_timer the
ifp->timer fires and:
addrconf_dad_timer(ifp)
addrconf_dad_completed(ifp)
ipv6_ifa_notify(RTM_NEWADDR, ifp)
ip6_ins_rt(ifp->rt)
then return back to the ipv6_del_addr and:
in6_ifa_put(ifp)
inet6_ifa_finish_destroy(ifp)
dst_release(&ifp->rt->u.dst)
After this we have an ifp->rt inserted into fib6 lists, but
queued for gc, which in turn can result in oopses in the
fib6_run_gc. Maybe some other nasty things, but we caught
only the oops in gc so far.
The solution is to disarm the ifp->timer before flushing the
rt from it.
Signed-off-by: Andrey Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/addrconf.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 147588f4c7c0..ff61a5cdb0b3 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -749,12 +749,12 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp) } write_unlock_bh(&idev->lock); + addrconf_del_timer(ifp); + ipv6_ifa_notify(RTM_DELADDR, ifp); atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp); - addrconf_del_timer(ifp); - /* * Purge or update corresponding prefix * |