}
/* All zeroes == unconditional rule. */
-static inline bool unconditional(const struct arpt_arp *arp)
+static inline bool unconditional(const struct arpt_entry *e)
{
static const struct arpt_arp uncond;
- return memcmp(arp, &uncond, sizeof(uncond)) == 0;
+ return e->target_offset == sizeof(struct arpt_entry) &&
+ memcmp(&e->arp, &uncond, sizeof(uncond)) == 0;
+}
+
+static bool find_jump_target(const struct xt_table_info *t,
+ const struct arpt_entry *target)
+{
+ struct arpt_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
|= ((1 << hook) | (1 << NF_ARP_NUMHOOKS));
/* Unconditional return/END. */
- if ((e->target_offset == sizeof(struct arpt_entry) &&
+ if ((unconditional(e) &&
(strcmp(t->target.u.user.name,
XT_STANDARD_TARGET) == 0) &&
- t->verdict < 0 && unconditional(&e->arp)) ||
- visited) {
+ t->verdict < 0) || visited) {
unsigned int oldpos, size;
if ((strcmp(t->target.u.user.name,
size = e->next_offset;
e = (struct arpt_entry *)
(entry0 + pos + size);
+ if (pos + size >= newinfo->size)
+ return 0;
e->counters.pcnt = pos;
pos += size;
} else {
/* This a jump; chase it. */
duprintf("Jump rule %u -> %u\n",
pos, newpos);
+ e = (struct arpt_entry *)
+ (entry0 + newpos);
+ if (!find_jump_target(newinfo, e))
+ return 0;
} else {
/* ... this is a fallthru */
newpos = pos + e->next_offset;
+ if (newpos >= newinfo->size)
+ return 0;
}
e = (struct arpt_entry *)
(entry0 + newpos);
return 1;
}
-static inline int check_entry(const struct arpt_entry *e, const char *name)
-{
- const struct xt_entry_target *t;
-
- if (!arp_checkentry(&e->arp)) {
- duprintf("arp_tables: arp check failed %p %s.\n", e, name);
- return -EINVAL;
- }
-
- if (e->target_offset + sizeof(struct xt_entry_target) > e->next_offset)
- return -EINVAL;
-
- t = arpt_get_target_c(e);
- if (e->target_offset + t->u.target_size > e->next_offset)
- return -EINVAL;
-
- return 0;
-}
-
static inline int check_target(struct arpt_entry *e, const char *name)
{
struct xt_entry_target *t = arpt_get_target(e);
struct xt_target *target;
int ret;
- ret = check_entry(e, name);
- if (ret)
- return ret;
-
e->counters.pcnt = xt_percpu_counter_alloc();
if (IS_ERR_VALUE(e->counters.pcnt))
return -ENOMEM;
const struct xt_entry_target *t;
unsigned int verdict;
- if (!unconditional(&e->arp))
+ if (!unconditional(e))
return false;
t = arpt_get_target_c(e);
if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
unsigned int valid_hooks)
{
unsigned int h;
+ int err;
if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 ||
- (unsigned char *)e + sizeof(struct arpt_entry) >= limit) {
+ (unsigned char *)e + sizeof(struct arpt_entry) >= limit ||
+ (unsigned char *)e + e->next_offset > limit) {
duprintf("Bad offset %p\n", e);
return -EINVAL;
}
return -EINVAL;
}
+ if (!arp_checkentry(&e->arp))
+ return -EINVAL;
+
+ err = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
+ if (err)
+ return err;
+
/* Check hooks & underflows */
for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
if (!(valid_hooks & (1 << h)))
newinfo->hook_entry[h] = hook_entries[h];
if ((unsigned char *)e - base == underflows[h]) {
if (!check_underflow(e)) {
- pr_err("Underflows must be unconditional and "
- "use the STANDARD target with "
- "ACCEPT/DROP\n");
+ pr_debug("Underflows must be unconditional and "
+ "use the STANDARD target with "
+ "ACCEPT/DROP\n");
return -EINVAL;
}
newinfo->underflow[h] = underflows[h];
}
}
- if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) {
- duprintf("Looping hook\n");
+ if (!mark_source_chains(newinfo, repl->valid_hooks, entry0))
return -ELOOP;
- }
/* Finally, each sanity check must pass */
i = 0;
sizeof(struct arpt_get_entries) + get.size);
return -EINVAL;
}
+ get.name[sizeof(get.name) - 1] = '\0';
t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
if (!IS_ERR_OR_NULL(t)) {
duprintf("check_compat_entry_size_and_hooks %p\n", e);
if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 ||
- (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit) {
+ (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit ||
+ (unsigned char *)e + e->next_offset > limit) {
duprintf("Bad offset %p, limit = %p\n", e, limit);
return -EINVAL;
}
return -EINVAL;
}
- /* For purposes of check_entry casting the compat entry is fine */
- ret = check_entry((struct arpt_entry *)e, name);
+ if (!arp_checkentry(&e->arp))
+ return -EINVAL;
+
+ ret = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
if (ret)
return ret;
*len, sizeof(get) + get.size);
return -EINVAL;
}
+ get.name[sizeof(get.name) - 1] = '\0';
xt_compat_lock(NFPROTO_ARP);
t = xt_find_table_lock(net, NFPROTO_ARP, get.name);