diff options
Diffstat (limited to 'net/sched/act_ct.c')
| -rw-r--r-- | net/sched/act_ct.c | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c index baac083fd8..9d451d77d5 100644 --- a/net/sched/act_ct.c +++ b/net/sched/act_ct.c @@ -41,21 +41,28 @@ static struct workqueue_struct *act_ct_wq; static struct rhashtable zones_ht; static DEFINE_MUTEX(zones_mutex); +struct zones_ht_key { + struct net *net; + u16 zone; + /* Note : pad[] must be the last field. */ + u8 pad[]; +}; + struct tcf_ct_flow_table { struct rhash_head node; /* In zones tables */ struct rcu_work rwork; struct nf_flowtable nf_ft; refcount_t ref; - u16 zone; + struct zones_ht_key key; bool dying; }; static const struct rhashtable_params zones_params = { .head_offset = offsetof(struct tcf_ct_flow_table, node), - .key_offset = offsetof(struct tcf_ct_flow_table, zone), - .key_len = sizeof_field(struct tcf_ct_flow_table, zone), + .key_offset = offsetof(struct tcf_ct_flow_table, key), + .key_len = offsetof(struct zones_ht_key, pad), .automatic_shrinking = true, }; @@ -316,11 +323,12 @@ static struct nf_flowtable_type flowtable_ct = { static int tcf_ct_flow_table_get(struct net *net, struct tcf_ct_params *params) { + struct zones_ht_key key = { .net = net, .zone = params->zone }; struct tcf_ct_flow_table *ct_ft; int err = -ENOMEM; mutex_lock(&zones_mutex); - ct_ft = rhashtable_lookup_fast(&zones_ht, ¶ms->zone, zones_params); + ct_ft = rhashtable_lookup_fast(&zones_ht, &key, zones_params); if (ct_ft && refcount_inc_not_zero(&ct_ft->ref)) goto out_unlock; @@ -329,7 +337,7 @@ static int tcf_ct_flow_table_get(struct net *net, struct tcf_ct_params *params) goto err_alloc; refcount_set(&ct_ft->ref, 1); - ct_ft->zone = params->zone; + ct_ft->key = key; err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params); if (err) goto err_insert; @@ -1071,6 +1079,14 @@ do_nat: */ if (nf_conntrack_confirm(skb) != NF_ACCEPT) goto drop; + + /* The ct may be dropped if a clash has been resolved, + * so it's necessary to retrieve it from skb again to + * prevent UAF. + */ + ct = nf_ct_get(skb, &ctinfo); + if (!ct) + skip_add = true; } if (!skip_add) |