diff options
| author | Florian Westphal <fw@strlen.de> | 2018-02-27 19:42:33 +0100 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2018-03-05 23:15:43 +0100 |
| commit | c84ca954ac9fa67a6ce27f91f01e4451c74fd8f6 (patch) | |
| tree | 3e3b78cb632b28a76a764889f71c8e77f1e440c9 | |
| parent | 9d5c12a7c08f67999772065afd50fb222072114e (diff) | |
netfilter: x_tables: add counters allocation wrapper
allows to have size checks in a single spot.
This is supposed to reduce oom situations when fuzz-testing xtables.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | include/linux/netfilter/x_tables.h | 1 | ||||
| -rw-r--r-- | net/ipv4/netfilter/arp_tables.c | 2 | ||||
| -rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 2 | ||||
| -rw-r--r-- | net/ipv6/netfilter/ip6_tables.c | 2 | ||||
| -rw-r--r-- | net/netfilter/x_tables.c | 15 |
5 files changed, 19 insertions, 3 deletions
diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h index fa0c19c328f1..0bd93c589a8c 100644 --- a/include/linux/netfilter/x_tables.h +++ b/include/linux/netfilter/x_tables.h @@ -301,6 +301,7 @@ int xt_data_to_user(void __user *dst, const void *src, void *xt_copy_counters_from_user(const void __user *user, unsigned int len, struct xt_counters_info *info, bool compat); +struct xt_counters *xt_counters_alloc(unsigned int counters); struct xt_table *xt_register_table(struct net *net, const struct xt_table *table, diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index be5821215ea0..82ba09b50fdb 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -883,7 +883,7 @@ static int __do_replace(struct net *net, const char *name, struct arpt_entry *iter; ret = 0; - counters = vzalloc(num_counters * sizeof(struct xt_counters)); + counters = xt_counters_alloc(num_counters); if (!counters) { ret = -ENOMEM; goto out; diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index 29bda9484a33..4901ca6c3e09 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -1045,7 +1045,7 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks, struct ipt_entry *iter; ret = 0; - counters = vzalloc(num_counters * sizeof(struct xt_counters)); + counters = xt_counters_alloc(num_counters); if (!counters) { ret = -ENOMEM; goto out; diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index ba3776a4d305..e84cec49b60f 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -1063,7 +1063,7 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks, struct ip6t_entry *iter; ret = 0; - counters = vzalloc(num_counters * sizeof(struct xt_counters)); + counters = xt_counters_alloc(num_counters); if (!counters) { ret = -ENOMEM; goto out; diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index 01f8e122e74e..82b1f8f52ac6 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -1290,6 +1290,21 @@ static int xt_jumpstack_alloc(struct xt_table_info *i) return 0; } +struct xt_counters *xt_counters_alloc(unsigned int counters) +{ + struct xt_counters *mem; + + if (counters == 0 || counters > INT_MAX / sizeof(*mem)) + return NULL; + + counters *= sizeof(*mem); + if (counters > XT_MAX_TABLE_SIZE) + return NULL; + + return vzalloc(counters); +} +EXPORT_SYMBOL(xt_counters_alloc); + struct xt_table_info * xt_replace_table(struct xt_table *table, unsigned int num_counters, |