From f6677f4312ee74f8ca68c4cc4060465607b72b41 Mon Sep 17 00:00:00 2001 From: Dmitry Mishin Date: Tue, 5 Dec 2006 13:44:07 -0800 Subject: [PATCH] [NETFILTER]: Fix iptables compat hook validation In compat mode, matches and targets valid hooks checks always successful due to not initialized e->comefrom field yet. This patch separates this checks from translation code and moves them after mark_source_chains() call, where these marks are initialized. Signed-off-by: Dmitry Mishin Signed-off-by; Patrick McHardy Signed-off-by: David S. Miller --- net/ipv4/netfilter/ip_tables.c | 78 ++++++++++++++++++++++------------ 1 file changed, 51 insertions(+), 27 deletions(-) diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index 2bddf8491982..0ff2956d35e5 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -1516,25 +1516,8 @@ static inline int compat_copy_match_from_user(struct ipt_entry_match *m, void **dstptr, compat_uint_t *size, const char *name, const struct ipt_ip *ip, unsigned int hookmask) { - struct ipt_entry_match *dm; - struct ipt_match *match; - int ret; - - dm = (struct ipt_entry_match *)*dstptr; - match = m->u.kernel.match; xt_compat_match_from_user(m, dstptr, size); - - ret = xt_check_match(match, AF_INET, dm->u.match_size - sizeof(*dm), - name, hookmask, ip->proto, - ip->invflags & IPT_INV_PROTO); - if (!ret && m->u.kernel.match->checkentry - && !m->u.kernel.match->checkentry(name, ip, match, dm->data, - hookmask)) { - duprintf("ip_tables: check failed for `%s'.\n", - m->u.kernel.match->name); - ret = -EINVAL; - } - return ret; + return 0; } static int compat_copy_entry_from_user(struct ipt_entry *e, void **dstptr, @@ -1556,7 +1539,7 @@ static int compat_copy_entry_from_user(struct ipt_entry *e, void **dstptr, ret = IPT_MATCH_ITERATE(e, compat_copy_match_from_user, dstptr, size, name, &de->ip, de->comefrom); if (ret) - goto err; + return ret; de->target_offset = e->target_offset - (origsize - *size); t = ipt_get_target(e); target = t->u.kernel.target; @@ -1569,26 +1552,62 @@ static int compat_copy_entry_from_user(struct ipt_entry *e, void **dstptr, if ((unsigned char *)de - base < newinfo->underflow[h]) newinfo->underflow[h] -= origsize - *size; } + return ret; +} + +static inline int compat_check_match(struct ipt_entry_match *m, const char *name, + const struct ipt_ip *ip, unsigned int hookmask) +{ + struct ipt_match *match; + int ret; + + match = m->u.kernel.match; + ret = xt_check_match(match, AF_INET, m->u.match_size - sizeof(*m), + name, hookmask, ip->proto, + ip->invflags & IPT_INV_PROTO); + if (!ret && m->u.kernel.match->checkentry + && !m->u.kernel.match->checkentry(name, ip, match, m->data, + hookmask)) { + duprintf("ip_tables: compat: check failed for `%s'.\n", + m->u.kernel.match->name); + ret = -EINVAL; + } + return ret; +} + +static inline int compat_check_target(struct ipt_entry *e, const char *name) +{ + struct ipt_entry_target *t; + struct ipt_target *target; + int ret; - t = ipt_get_target(de); + t = ipt_get_target(e); target = t->u.kernel.target; ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t), name, e->comefrom, e->ip.proto, e->ip.invflags & IPT_INV_PROTO); - if (ret) - goto err; - - if (t->u.kernel.target->checkentry - && !t->u.kernel.target->checkentry(name, de, target, - t->data, de->comefrom)) { + if (!ret && t->u.kernel.target->checkentry + && !t->u.kernel.target->checkentry(name, e, target, + t->data, e->comefrom)) { duprintf("ip_tables: compat: check failed for `%s'.\n", t->u.kernel.target->name); ret = -EINVAL; } -err: return ret; } +static inline int compat_check_entry(struct ipt_entry *e, const char *name) +{ + int ret; + + ret = IPT_MATCH_ITERATE(e, compat_check_match, name, &e->ip, + e->comefrom); + if (ret) + return ret; + + return compat_check_target(e, name); +} + static int translate_compat_table(const char *name, unsigned int valid_hooks, @@ -1677,6 +1696,11 @@ translate_compat_table(const char *name, if (!mark_source_chains(newinfo, valid_hooks, entry1)) goto free_newinfo; + ret = IPT_ENTRY_ITERATE(entry1, newinfo->size, compat_check_entry, + name); + if (ret) + goto free_newinfo; + /* And one copy for every other CPU */ for_each_possible_cpu(i) if (newinfo->entries[i] && newinfo->entries[i] != entry1) -- 2.30.2