diff options
Diffstat (limited to 'net/ipv4/netfilter/ip_tables.c')
| -rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 65 |
1 files changed, 38 insertions, 27 deletions
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index a399c5419622..8adb6e9ba8f5 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -408,6 +408,10 @@ ipt_do_table(struct sk_buff *skb, } if (table_base + v != ipt_next_entry(e) && !(e->ip.flags & IPT_F_GOTO)) { + if (unlikely(stackidx >= private->stacksize)) { + verdict = NF_DROP; + break; + } jumpstack[stackidx++] = e; pr_debug("Pushed %p into pos %u\n", e, stackidx - 1); @@ -443,23 +447,12 @@ ipt_do_table(struct sk_buff *skb, #endif } -static bool find_jump_target(const struct xt_table_info *t, - const struct ipt_entry *target) -{ - struct ipt_entry *iter; - - xt_entry_foreach(iter, t->entries, t->size) { - if (iter == target) - return true; - } - return false; -} - /* Figures out from what hook each rule can be called: returns 0 if there are loops. Puts hook bitmask in comefrom. */ static int mark_source_chains(const struct xt_table_info *newinfo, - unsigned int valid_hooks, void *entry0) + unsigned int valid_hooks, void *entry0, + unsigned int *offsets) { unsigned int hook; @@ -552,10 +545,11 @@ mark_source_chains(const struct xt_table_info *newinfo, /* This a jump; chase it. */ duprintf("Jump rule %u -> %u\n", pos, newpos); + if (!xt_find_jump_offset(offsets, newpos, + newinfo->number)) + return 0; e = (struct ipt_entry *) (entry0 + newpos); - if (!find_jump_target(newinfo, e)) - return 0; } else { /* ... this is a fallthru */ newpos = pos + e->next_offset; @@ -655,7 +649,8 @@ static int check_target(struct ipt_entry *e, struct net *net, const char *name) static int find_check_entry(struct ipt_entry *e, struct net *net, const char *name, - unsigned int size) + unsigned int size, + struct xt_percpu_counter_alloc_state *alloc_state) { struct xt_entry_target *t; struct xt_target *target; @@ -664,11 +659,11 @@ find_check_entry(struct ipt_entry *e, struct net *net, const char *name, struct xt_mtchk_param mtpar; struct xt_entry_match *ematch; - e->counters.pcnt = xt_percpu_counter_alloc(); - if (IS_ERR_VALUE(e->counters.pcnt)) + if (!xt_percpu_counter_alloc(alloc_state, &e->counters)) return -ENOMEM; j = 0; + memset(&mtpar, 0, sizeof(mtpar)); mtpar.net = net; mtpar.table = name; mtpar.entryinfo = &e->ip; @@ -705,7 +700,7 @@ find_check_entry(struct ipt_entry *e, struct net *net, const char *name, cleanup_match(ematch, net); } - xt_percpu_counter_free(e->counters.pcnt); + xt_percpu_counter_free(&e->counters); return ret; } @@ -801,7 +796,7 @@ cleanup_entry(struct ipt_entry *e, struct net *net) if (par.target->destroy != NULL) par.target->destroy(&par); module_put(par.target->me); - xt_percpu_counter_free(e->counters.pcnt); + xt_percpu_counter_free(&e->counters); } /* Checks and translates the user-supplied table segment (held in @@ -810,7 +805,9 @@ static int translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, const struct ipt_replace *repl) { + struct xt_percpu_counter_alloc_state alloc_state = { 0 }; struct ipt_entry *iter; + unsigned int *offsets; unsigned int i; int ret = 0; @@ -824,6 +821,9 @@ translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, } duprintf("translate_table: size %u\n", newinfo->size); + offsets = xt_alloc_entry_offsets(newinfo->number); + if (!offsets) + return -ENOMEM; i = 0; /* Walk through entries, checking offsets. */ xt_entry_foreach(iter, entry0, newinfo->size) { @@ -833,17 +833,20 @@ translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, repl->underflow, repl->valid_hooks); if (ret != 0) - return ret; + goto out_free; + if (i < repl->num_entries) + offsets[i] = (void *)iter - entry0; ++i; if (strcmp(ipt_get_target(iter)->u.user.name, XT_ERROR_TARGET) == 0) ++newinfo->stacksize; } + ret = -EINVAL; if (i != repl->num_entries) { duprintf("translate_table: %u not %u entries\n", i, repl->num_entries); - return -EINVAL; + goto out_free; } /* Check hooks all assigned */ @@ -854,22 +857,26 @@ translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, if (newinfo->hook_entry[i] == 0xFFFFFFFF) { duprintf("Invalid hook entry %u %u\n", i, repl->hook_entry[i]); - return -EINVAL; + goto out_free; } if (newinfo->underflow[i] == 0xFFFFFFFF) { duprintf("Invalid underflow %u %u\n", i, repl->underflow[i]); - return -EINVAL; + goto out_free; } } - if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) - return -ELOOP; + if (!mark_source_chains(newinfo, repl->valid_hooks, entry0, offsets)) { + ret = -ELOOP; + goto out_free; + } + kvfree(offsets); /* Finally, each sanity check must pass */ i = 0; xt_entry_foreach(iter, entry0, newinfo->size) { - ret = find_check_entry(iter, net, repl->name, repl->size); + ret = find_check_entry(iter, net, repl->name, repl->size, + &alloc_state); if (ret != 0) break; ++i; @@ -885,6 +892,9 @@ translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, } return ret; + out_free: + kvfree(offsets); + return ret; } static void @@ -2062,6 +2072,7 @@ static struct xt_match ipt_builtin_mt[] __read_mostly = { .checkentry = icmp_checkentry, .proto = IPPROTO_ICMP, .family = NFPROTO_IPV4, + .me = THIS_MODULE, }, }; |