From 8dddd32756f6fe8e4e82a63361119b7e2384e02f Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 1 Apr 2016 14:17:32 +0200 Subject: [PATCH] netfilter: arp_tables: simplify translate_compat_table args Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/ipv4/netfilter/arp_tables.c | 82 +++++++++++++++------------------ 1 file changed, 36 insertions(+), 46 deletions(-) diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index 95ed4e454c60..1d1386dc159b 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -1214,6 +1214,18 @@ 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; @@ -1229,8 +1241,7 @@ check_compat_entry_size_and_hooks(struct compat_arpt_entry *e, 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; @@ -1301,7 +1312,7 @@ out: 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; @@ -1334,14 +1345,9 @@ compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr, 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; @@ -1353,8 +1359,8 @@ static int translate_compat_table(const char *name, 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++) { @@ -1365,40 +1371,39 @@ static int translate_compat_table(const char *name, 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; } } @@ -1408,17 +1413,17 @@ static int translate_compat_table(const char *name, 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; } @@ -1428,7 +1433,7 @@ static int translate_compat_table(const char *name, 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; @@ -1439,7 +1444,7 @@ static int translate_compat_table(const char *name, break; } - ret = check_target(iter1, name); + ret = check_target(iter1, compatr->name); if (ret != 0) { xt_percpu_counter_free(iter1->counters.pcnt); break; @@ -1481,7 +1486,7 @@ static int translate_compat_table(const char *name, 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); @@ -1493,18 +1498,6 @@ out_unlock: 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) { @@ -1537,10 +1530,7 @@ 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; -- 2.20.1