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>
diff --git a/net/core/dev.c b/net/core/dev.c
index 84f01ba..0f28a9e 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2444,8 +2444,12 @@
{
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)