}
/* 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;
unsigned int i;
struct xt_counters_info tmp;
struct xt_counters *paddc;
- unsigned int num_counters;
- const char *name;
- int size;
- void *ptmp;
struct xt_table *t;
const struct xt_table_info *private;
int ret = 0;
struct arpt_entry *iter;
unsigned int addend;
-#ifdef CONFIG_COMPAT
- struct compat_xt_counters_info compat_tmp;
-
- if (compat) {
- ptmp = &compat_tmp;
- size = sizeof(struct compat_xt_counters_info);
- } else
-#endif
- {
- ptmp = &tmp;
- size = sizeof(struct xt_counters_info);
- }
- if (copy_from_user(ptmp, user, size) != 0)
- return -EFAULT;
-
-#ifdef CONFIG_COMPAT
- if (compat) {
- num_counters = compat_tmp.num_counters;
- name = compat_tmp.name;
- } else
-#endif
- {
- num_counters = tmp.num_counters;
- name = tmp.name;
- }
+ paddc = xt_copy_counters_from_user(user, len, &tmp, compat);
+ if (IS_ERR(paddc))
+ return PTR_ERR(paddc);
- if (len != size + num_counters * sizeof(struct xt_counters))
- return -EINVAL;
-
- paddc = vmalloc(len - size);
- if (!paddc)
- return -ENOMEM;
-
- if (copy_from_user(paddc, user + size, len - size) != 0) {
- ret = -EFAULT;
- goto free;
- }
-
- t = xt_find_table_lock(net, NFPROTO_ARP, name);
+ t = xt_find_table_lock(net, NFPROTO_ARP, tmp.name);
if (IS_ERR_OR_NULL(t)) {
ret = t ? PTR_ERR(t) : -ENOENT;
goto free;
local_bh_disable();
private = t->private;
- if (private->number != num_counters) {
+ if (private->number != tmp.num_counters) {
ret = -EINVAL;
goto unlock_up_free;
}
}
#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;
module_put(t->u.kernel.target->me);
}
-static inline int
+static int
check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
struct xt_table_info *newinfo,
unsigned int *size,
const unsigned char *base,
- const unsigned char *limit,
- const unsigned int *hook_entries,
- const unsigned int *underflows,
- const char *name)
+ const unsigned char *limit)
{
struct xt_entry_target *t;
struct xt_target *target;
unsigned int entry_offset;
- int ret, off, h;
+ int ret, off;
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;
if (ret)
goto release_target;
- /* Check hooks & underflows */
- for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
- if ((unsigned char *)e - base == hook_entries[h])
- newinfo->hook_entry[h] = hook_entries[h];
- if ((unsigned char *)e - base == underflows[h])
- newinfo->underflow[h] = underflows[h];
- }
-
- /* Clear counters and comefrom */
- memset(&e->counters, 0, sizeof(e->counters));
- e->comefrom = 0;
return 0;
release_target:
return ret;
}
-static int
+static void
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;
struct xt_target *target;
struct arpt_entry *de;
unsigned int origsize;
- int ret, h;
+ int h;
- ret = 0;
origsize = *size;
de = (struct arpt_entry *)*dstptr;
memcpy(de, e, sizeof(struct arpt_entry));
if ((unsigned char *)de - base < newinfo->underflow[h])
newinfo->underflow[h] -= origsize - *size;
}
- 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;
void *pos, *entry0, *entry1;
struct compat_arpt_entry *iter0;
- struct arpt_entry *iter1;
+ struct arpt_replace repl;
unsigned int size;
int ret = 0;
info = *pinfo;
entry0 = *pentry0;
- size = total_size;
- info->number = number;
-
- /* Init all hooks to impossible value. */
- for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
- info->hook_entry[i] = 0xFFFFFFFF;
- info->underflow[i] = 0xFFFFFFFF;
- }
+ size = compatr->size;
+ info->number = compatr->num_entries;
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);
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)))
- continue;
- if (info->hook_entry[i] == 0xFFFFFFFF) {
- duprintf("Invalid hook entry %u %u\n",
- i, hook_entries[i]);
- goto out_unlock;
- }
- if (info->underflow[i] == 0xFFFFFFFF) {
- duprintf("Invalid underflow %u %u\n",
- i, underflows[i]);
- goto out_unlock;
- }
- }
-
ret = -ENOMEM;
newinfo = xt_alloc_table_info(size);
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) {
- ret = compat_copy_entry_from_user(iter0, &pos, &size,
- name, newinfo, entry1);
- if (ret != 0)
- break;
- }
+ size = compatr->size;
+ xt_entry_foreach(iter0, entry0, compatr->size)
+ compat_copy_entry_from_user(iter0, &pos, &size,
+ newinfo, entry1);
+
+ /* all module references in entry0 are now gone */
+
xt_compat_flush_offsets(NFPROTO_ARP);
xt_compat_unlock(NFPROTO_ARP);
- if (ret)
- goto free_newinfo;
- ret = -ELOOP;
- if (!mark_source_chains(newinfo, valid_hooks, entry1))
- goto free_newinfo;
+ memcpy(&repl, compatr, sizeof(*compatr));
- i = 0;
- xt_entry_foreach(iter1, entry1, newinfo->size) {
- iter1->counters.pcnt = xt_percpu_counter_alloc();
- if (IS_ERR_VALUE(iter1->counters.pcnt)) {
- ret = -ENOMEM;
- break;
- }
-
- ret = check_target(iter1, name);
- if (ret != 0) {
- xt_percpu_counter_free(iter1->counters.pcnt);
- break;
- }
- ++i;
- if (strcmp(arpt_get_target(iter1)->u.user.name,
- XT_ERROR_TARGET) == 0)
- ++newinfo->stacksize;
- }
- if (ret) {
- /*
- * The first i matches need cleanup_entry (calls ->destroy)
- * because they had called ->check already. The other j-i
- * entries need only release.
- */
- int skip = i;
- j -= i;
- xt_entry_foreach(iter0, entry0, newinfo->size) {
- if (skip-- > 0)
- continue;
- if (j-- == 0)
- break;
- compat_release_entry(iter0);
- }
- xt_entry_foreach(iter1, entry1, newinfo->size) {
- if (i-- == 0)
- break;
- cleanup_entry(iter1);
- }
- xt_free_table_info(newinfo);
- return ret;
+ for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
+ repl.hook_entry[i] = newinfo->hook_entry[i];
+ repl.underflow[i] = newinfo->underflow[i];
}
+ repl.num_counters = 0;
+ repl.counters = NULL;
+ repl.size = newinfo->size;
+ ret = translate_table(newinfo, entry1, &repl);
+ if (ret)
+ goto free_newinfo;
+
*pinfo = newinfo;
*pentry0 = entry1;
xt_free_table_info(info);
free_newinfo:
xt_free_table_info(newinfo);
-out:
- xt_entry_foreach(iter0, entry0, total_size) {
+ return ret;
+out_unlock:
+ xt_compat_flush_offsets(NFPROTO_ARP);
+ xt_compat_unlock(NFPROTO_ARP);
+ xt_entry_foreach(iter0, entry0, compatr->size) {
if (j-- == 0)
break;
compat_release_entry(iter0);
}
return ret;
-out_unlock:
- xt_compat_flush_offsets(NFPROTO_ARP);
- xt_compat_unlock(NFPROTO_ARP);
- 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;
Code Review / kvmfornfv.git / blobdiff