}
/* 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->elems, 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;
}
#ifdef CONFIG_COMPAT
+struct compat_arpt_replace {
+ char name[XT_TABLE_MAXNAMELEN];
+ u32 valid_hooks;
+ u32 num_entries;
+ u32 size;
+ u32 hook_entry[NF_ARP_NUMHOOKS];
+ u32 underflow[NF_ARP_NUMHOOKS];
+ u32 num_counters;
+ compat_uptr_t counters;
+ struct compat_arpt_entry entries[0];
+};
+
static inline void compat_release_entry(struct compat_arpt_entry *e)
{
struct xt_entry_target *t;
const unsigned char *base,
const unsigned char *limit,
const unsigned int *hook_entries,
- const unsigned int *underflows,
- const char *name)
+ const unsigned int *underflows)
{
struct xt_entry_target *t;
struct xt_target *target;
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_compat_check_entry_offsets(e, e->elems, e->target_offset,
+ e->next_offset);
if (ret)
return ret;
static int
compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr,
- unsigned int *size, const char *name,
+ unsigned int *size,
struct xt_table_info *newinfo, unsigned char *base)
{
struct xt_entry_target *t;
return ret;
}
-static int translate_compat_table(const char *name,
- unsigned int valid_hooks,
- struct xt_table_info **pinfo,
+static int translate_compat_table(struct xt_table_info **pinfo,
void **pentry0,
- unsigned int total_size,
- unsigned int number,
- unsigned int *hook_entries,
- unsigned int *underflows)
+ const struct compat_arpt_replace *compatr)
{
unsigned int i, j;
struct xt_table_info *newinfo, *info;
info = *pinfo;
entry0 = *pentry0;
- size = total_size;
- info->number = number;
+ size = compatr->size;
+ info->number = compatr->num_entries;
/* Init all hooks to impossible value. */
for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
duprintf("translate_compat_table: size %u\n", info->size);
j = 0;
xt_compat_lock(NFPROTO_ARP);
- xt_compat_init_offsets(NFPROTO_ARP, number);
+ xt_compat_init_offsets(NFPROTO_ARP, compatr->num_entries);
/* Walk through entries, checking offsets. */
- xt_entry_foreach(iter0, entry0, total_size) {
+ xt_entry_foreach(iter0, entry0, compatr->size) {
ret = check_compat_entry_size_and_hooks(iter0, info, &size,
entry0,
- entry0 + total_size,
- hook_entries,
- underflows,
- name);
+ entry0 + compatr->size,
+ compatr->hook_entry,
+ compatr->underflow);
if (ret != 0)
goto out_unlock;
++j;
}
ret = -EINVAL;
- if (j != number) {
+ if (j != compatr->num_entries) {
duprintf("translate_compat_table: %u not %u entries\n",
- j, number);
+ j, compatr->num_entries);
goto out_unlock;
}
/* Check hooks all assigned */
for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
/* Only hooks which are valid */
- if (!(valid_hooks & (1 << i)))
+ if (!(compatr->valid_hooks & (1 << i)))
continue;
if (info->hook_entry[i] == 0xFFFFFFFF) {
duprintf("Invalid hook entry %u %u\n",
- i, hook_entries[i]);
+ i, info->hook_entry[i]);
goto out_unlock;
}
if (info->underflow[i] == 0xFFFFFFFF) {
duprintf("Invalid underflow %u %u\n",
- i, underflows[i]);
+ i, info->underflow[i]);
goto out_unlock;
}
}
if (!newinfo)
goto out_unlock;
- newinfo->number = number;
+ newinfo->number = compatr->num_entries;
for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
newinfo->hook_entry[i] = info->hook_entry[i];
newinfo->underflow[i] = info->underflow[i];
}
entry1 = newinfo->entries;
pos = entry1;
- size = total_size;
- xt_entry_foreach(iter0, entry0, total_size) {
+ size = compatr->size;
+ xt_entry_foreach(iter0, entry0, compatr->size) {
ret = compat_copy_entry_from_user(iter0, &pos, &size,
- name, newinfo, entry1);
+ newinfo, entry1);
if (ret != 0)
break;
}
goto free_newinfo;
ret = -ELOOP;
- if (!mark_source_chains(newinfo, valid_hooks, entry1))
+ if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1))
goto free_newinfo;
i = 0;
break;
}
- ret = check_target(iter1, name);
+ ret = check_target(iter1, compatr->name);
if (ret != 0) {
xt_percpu_counter_free(iter1->counters.pcnt);
break;
free_newinfo:
xt_free_table_info(newinfo);
out:
- xt_entry_foreach(iter0, entry0, total_size) {
+ xt_entry_foreach(iter0, entry0, compatr->size) {
if (j-- == 0)
break;
compat_release_entry(iter0);
goto out;
}
-struct compat_arpt_replace {
- char name[XT_TABLE_MAXNAMELEN];
- u32 valid_hooks;
- u32 num_entries;
- u32 size;
- u32 hook_entry[NF_ARP_NUMHOOKS];
- u32 underflow[NF_ARP_NUMHOOKS];
- u32 num_counters;
- compat_uptr_t counters;
- struct compat_arpt_entry entries[0];
-};
-
static int compat_do_replace(struct net *net, void __user *user,
unsigned int len)
{
goto free_newinfo;
}
- ret = translate_compat_table(tmp.name, tmp.valid_hooks,
- &newinfo, &loc_cpu_entry, tmp.size,
- tmp.num_entries, tmp.hook_entry,
- tmp.underflow);
+ ret = translate_compat_table(&newinfo, &loc_cpu_entry, &tmp);
if (ret != 0)
goto free_newinfo;