diff options
| author | Thomas Graf <tgraf@suug.ch> | 2012-06-14 23:00:17 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-06-15 15:30:15 -0700 |
| commit | 2a0c451ade8e1783c5d453948289e4a978d417c9 (patch) | |
| tree | 136dbbaf024f45200848ec371368668872545a2e /net | |
| parent | 0f6efff92524c65fc3ef41c8b936c526580f1db0 (diff) | |
| download | lwn-2a0c451ade8e1783c5d453948289e4a978d417c9.tar.gz lwn-2a0c451ade8e1783c5d453948289e4a978d417c9.zip | |
ipv6: Prevent access to uninitialized fib_table_hash via /proc/net/ipv6_route
/proc/net/ipv6_route reflects the contents of fib_table_hash. The proc
handler is installed in ip6_route_net_init() whereas fib_table_hash is
allocated in fib6_net_init() _after_ the proc handler has been installed.
This opens up a short time frame to access fib_table_hash with its pants
down.
fib6_init() as a whole can't be moved to an earlier position as it also
registers the rtnetlink message handlers which should be registered at
the end. Therefore split it into fib6_init() which is run early and
fib6_init_late() to register the rtnetlink message handlers.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Reviewed-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/ip6_fib.c | 18 | ||||
| -rw-r--r-- | net/ipv6/route.c | 16 |
2 files changed, 22 insertions, 12 deletions
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index 74c21b924a79..fbd4afff05fa 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -1692,21 +1692,25 @@ int __init fib6_init(void) ret = register_pernet_subsys(&fib6_net_ops); if (ret) goto out_kmem_cache_create; - - ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib, - NULL); - if (ret) - goto out_unregister_subsys; out: return ret; -out_unregister_subsys: - unregister_pernet_subsys(&fib6_net_ops); out_kmem_cache_create: kmem_cache_destroy(fib6_node_kmem); goto out; } +int __init fib6_init_late(void) +{ + return __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib, + NULL); +} + +void fib6_cleanup_late(void) +{ + rtnl_unregister(PF_INET6, RTM_GETROUTE); +} + void fib6_gc_cleanup(void) { unregister_pernet_subsys(&fib6_net_ops); diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 999a982ad3fd..dc60bf585966 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -3018,10 +3018,14 @@ int __init ip6_route_init(void) if (ret) goto out_kmem_cache; - ret = register_pernet_subsys(&ip6_route_net_ops); + ret = fib6_init(); if (ret) goto out_dst_entries; + ret = register_pernet_subsys(&ip6_route_net_ops); + if (ret) + goto out_fib6_init; + ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep; /* Registering of the loopback is done before this portion of code, @@ -3035,13 +3039,13 @@ int __init ip6_route_init(void) init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev; init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); #endif - ret = fib6_init(); + ret = fib6_init_late(); if (ret) goto out_register_subsys; ret = xfrm6_init(); if (ret) - goto out_fib6_init; + goto out_fib6_init_late; ret = fib6_rules_init(); if (ret) @@ -3064,10 +3068,12 @@ fib6_rules_init: fib6_rules_cleanup(); xfrm6_init: xfrm6_fini(); -out_fib6_init: - fib6_gc_cleanup(); +out_fib6_init_late: + fib6_cleanup_late(); out_register_subsys: unregister_pernet_subsys(&ip6_route_net_ops); +out_fib6_init: + fib6_gc_cleanup(); out_dst_entries: dst_entries_destroy(&ip6_dst_blackhole_ops); out_kmem_cache: |