diff options
author | Eric Dumazet <edumazet@google.com> | 2012-07-08 21:45:10 +0000 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2012-07-09 14:50:54 -0700 |
commit | 91c68ce2b26319248a32d7baa1226f819d283758 (patch) | |
tree | eeeea052a0b13d2f97435fe33caa5139e4729a53 | |
parent | 96ca7ffe748bf91f851e6aa4479aa11c8b1122ba (diff) | |
download | blackbird-op-linux-91c68ce2b26319248a32d7baa1226f819d283758.tar.gz blackbird-op-linux-91c68ce2b26319248a32d7baa1226f819d283758.zip |
net: cgroup: fix out of bounds accesses
dev->priomap is allocated by extend_netdev_table() called from
update_netdev_tables().
And this is only called if write_priomap() is called.
But if write_priomap() is not called, it seems we can have out of bounds
accesses in cgrp_destroy(), read_priomap() & skb_update_prio()
With help from Gao Feng
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Gao feng <gaofeng@cn.fujitsu.com>
Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/core/dev.c | 8 | ||||
-rw-r--r-- | net/core/netprio_cgroup.c | 4 |
2 files changed, 8 insertions, 4 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 84f01ba81a34..0f28a9e0b8ad 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2444,8 +2444,12 @@ static void skb_update_prio(struct sk_buff *skb) { struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap); - if ((!skb->priority) && (skb->sk) && map) - skb->priority = map->priomap[skb->sk->sk_cgrp_prioidx]; + if (!skb->priority && skb->sk && map) { + unsigned int prioidx = skb->sk->sk_cgrp_prioidx; + + if (prioidx < map->priomap_len) + skb->priority = map->priomap[prioidx]; + } } #else #define skb_update_prio(skb) diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c index aa907ed466ea..3e953eaddbfc 100644 --- a/net/core/netprio_cgroup.c +++ b/net/core/netprio_cgroup.c @@ -142,7 +142,7 @@ static void cgrp_destroy(struct cgroup *cgrp) rtnl_lock(); for_each_netdev(&init_net, dev) { map = rtnl_dereference(dev->priomap); - if (map) + if (map && cs->prioidx < map->priomap_len) map->priomap[cs->prioidx] = 0; } rtnl_unlock(); @@ -166,7 +166,7 @@ static int read_priomap(struct cgroup *cont, struct cftype *cft, rcu_read_lock(); for_each_netdev_rcu(&init_net, dev) { map = rcu_dereference(dev->priomap); - priority = map ? map->priomap[prioidx] : 0; + priority = (map && prioidx < map->priomap_len) ? map->priomap[prioidx] : 0; cb->fill(cb, dev->name, priority); } rcu_read_unlock(); |