Merge tag 'v3.10.103' into update
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / ipv4 / netfilter / arp_tables.c
index e4717743316e39f88aeac5f32a97bae61b0e3439..bb1670b371d2050524269539cd9b506899ff0562 100644 (file)
@@ -355,7 +355,7 @@ static inline bool unconditional(const struct arpt_entry *e)
        static const struct arpt_arp uncond;
 
        return e->target_offset == sizeof(struct arpt_entry) &&
-               memcmp(&e->arp, &uncond, sizeof(uncond)) == 0;
+              memcmp(&e->arp, &uncond, sizeof(uncond)) == 0;
 }
 
 /* Figures out from what hook each rule can be called: returns 0 if
@@ -430,6 +430,8 @@ static int mark_source_chains(const struct xt_table_info *newinfo,
                                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 {
@@ -452,6 +454,8 @@ static int mark_source_chains(const struct xt_table_info *newinfo,
                                } else {
                                        /* ... this is a fallthru */
                                        newpos = pos + e->next_offset;
+                                       if (newpos >= newinfo->size)
+                                               return 0;
                                }
                                e = (struct arpt_entry *)
                                        (entry0 + newpos);
@@ -482,7 +486,6 @@ static inline int check_entry(const struct arpt_entry *e)
        return 0;
 }
 
-
 static inline int check_target(struct arpt_entry *e, const char *name)
 {
        struct xt_entry_target *t = arpt_get_target(e);
@@ -573,6 +576,7 @@ static inline int check_entry_size_and_hooks(struct arpt_entry *e,
        }
 
        err = check_entry(e);
+
        if (err)
                return err;
 
@@ -584,9 +588,9 @@ static inline int check_entry_size_and_hooks(struct arpt_entry *e,
                        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];
@@ -676,10 +680,8 @@ static int translate_table(struct xt_table_info *newinfo, void *entry0,
                }
        }
 
-       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;
@@ -1072,6 +1074,9 @@ static int do_replace(struct net *net, const void __user *user,
        /* overflow check */
        if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
                return -ENOMEM;
+       if (tmp.num_counters == 0)
+               return -EINVAL;
+
        tmp.name[sizeof(tmp.name)-1] = 0;
 
        newinfo = xt_alloc_table_info(tmp.size);
@@ -1112,56 +1117,18 @@ static int do_add_counters(struct net *net, const void __user *user,
        unsigned int i, curcpu;
        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;
        void *loc_cpu_entry;
        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);
-       }
+       paddc = xt_copy_counters_from_user(user, len, &tmp, compat);
+       if (IS_ERR(paddc))
+               return PTR_ERR(paddc);
 
-       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;
-       }
-
-       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;
@@ -1169,7 +1136,7 @@ static int do_add_counters(struct net *net, const void __user *user,
 
        local_bh_disable();
        private = t->private;
-       if (private->number != num_counters) {
+       if (private->number != tmp.num_counters) {
                ret = -EINVAL;
                goto unlock_up_free;
        }
@@ -1195,6 +1162,18 @@ static int do_add_counters(struct net *net, const void __user *user,
 }
 
 #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;
@@ -1203,20 +1182,17 @@ static inline void compat_release_entry(struct compat_arpt_entry *e)
        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 ||
@@ -1235,6 +1211,7 @@ check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
 
        /* For purposes of check_entry casting the compat entry is fine */
        ret = check_entry((struct arpt_entry *)e);
+
        if (ret)
                return ret;
 
@@ -1258,17 +1235,6 @@ check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
        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:
@@ -1277,18 +1243,17 @@ out:
        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));
@@ -1309,144 +1274,81 @@ compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr,
                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[raw_smp_processor_id()];
        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) {
-               ret = check_target(iter1, name);
-               if (ret != 0)
-                       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];
        }
 
-       /* And one copy for every other CPU */
-       for_each_possible_cpu(i)
-               if (newinfo->entries[i] && newinfo->entries[i] != entry1)
-                       memcpy(newinfo->entries[i], entry1, newinfo->size);
+       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;
@@ -1455,31 +1357,18 @@ static int translate_compat_table(const char *name,
 
 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)
 {
@@ -1497,6 +1386,9 @@ static int compat_do_replace(struct net *net, void __user *user,
                return -ENOMEM;
        if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
                return -ENOMEM;
+       if (tmp.num_counters == 0)
+               return -EINVAL;
+
        tmp.name[sizeof(tmp.name)-1] = 0;
 
        newinfo = xt_alloc_table_info(tmp.size);
@@ -1510,10 +1402,7 @@ static int compat_do_replace(struct net *net, void __user *user,
                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;