From 98dbbfc3f1a555194e784304d930d2aafde3e2a3 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 26 Aug 2015 23:20:51 +0200 Subject: Revert "netfilter: xtables: compute exact size needed for jumpstack" This reverts commit 98d1bd802cdbc8f56868fae51edec13e86b59515. mark_source_chains will not re-visit chains, so *filter :INPUT ACCEPT [365:25776] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [217:45832] :t1 - [0:0] :t2 - [0:0] :t3 - [0:0] :t4 - [0:0] -A t1 -i lo -j t2 -A t2 -i lo -j t3 -A t3 -i lo -j t4 # -A INPUT -j t4 # -A INPUT -j t3 # -A INPUT -j t2 -A INPUT -j t1 COMMIT Will compute a chain depth of 2 if the comments are removed. Revert back to counting the number of chains for the time being. Reported-by: Cong Wang Reported-by: Hannes Frederic Sowa Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index c416cb3..8f87fc3 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -367,13 +367,10 @@ static inline bool unconditional(const struct arpt_arp *arp) /* Figures out from what hook each rule can be called: returns 0 if * there are loops. Puts hook bitmask in comefrom. - * - * Keeps track of largest call depth seen and stores it in newinfo->stacksize. */ -static int mark_source_chains(struct xt_table_info *newinfo, +static int mark_source_chains(const struct xt_table_info *newinfo, unsigned int valid_hooks, void *entry0) { - unsigned int calldepth, max_calldepth = 0; unsigned int hook; /* No recursion; use packet counter to save back ptrs (reset @@ -389,7 +386,6 @@ static int mark_source_chains(struct xt_table_info *newinfo, /* Set initial back pointer. */ e->counters.pcnt = pos; - calldepth = 0; for (;;) { const struct xt_standard_target *t @@ -444,8 +440,6 @@ static int mark_source_chains(struct xt_table_info *newinfo, (entry0 + pos + size); e->counters.pcnt = pos; pos += size; - if (calldepth > 0) - --calldepth; } else { int newpos = t->verdict; @@ -460,10 +454,6 @@ static int mark_source_chains(struct xt_table_info *newinfo, return 0; } - if (entry0 + newpos != arpt_next_entry(e) && - ++calldepth > max_calldepth) - max_calldepth = calldepth; - /* This a jump; chase it. */ duprintf("Jump rule %u -> %u\n", pos, newpos); @@ -480,7 +470,6 @@ static int mark_source_chains(struct xt_table_info *newinfo, next: duprintf("Finished chain %u\n", hook); } - newinfo->stacksize = max_calldepth; return 1; } @@ -670,6 +659,9 @@ static int translate_table(struct xt_table_info *newinfo, void *entry0, if (ret != 0) break; ++i; + if (strcmp(arpt_get_target(iter)->u.user.name, + XT_ERROR_TARGET) == 0) + ++newinfo->stacksize; } duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret); if (ret != 0) @@ -1442,6 +1434,9 @@ static int translate_compat_table(const char *name, break; } ++i; + if (strcmp(arpt_get_target(iter1)->u.user.name, + XT_ERROR_TARGET) == 0) + ++newinfo->stacksize; } if (ret) { /* diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index 787f99e..b0a86e7 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -443,15 +443,11 @@ ipt_do_table(struct sk_buff *skb, } /* Figures out from what hook each rule can be called: returns 0 if - * there are loops. Puts hook bitmask in comefrom. - * - * Keeps track of largest call depth seen and stores it in newinfo->stacksize. - */ + there are loops. Puts hook bitmask in comefrom. */ static int -mark_source_chains(struct xt_table_info *newinfo, +mark_source_chains(const struct xt_table_info *newinfo, unsigned int valid_hooks, void *entry0) { - unsigned int calldepth, max_calldepth = 0; unsigned int hook; /* No recursion; use packet counter to save back ptrs (reset @@ -465,7 +461,6 @@ mark_source_chains(struct xt_table_info *newinfo, /* Set initial back pointer. */ e->counters.pcnt = pos; - calldepth = 0; for (;;) { const struct xt_standard_target *t @@ -527,9 +522,6 @@ mark_source_chains(struct xt_table_info *newinfo, (entry0 + pos + size); e->counters.pcnt = pos; pos += size; - WARN_ON_ONCE(calldepth == 0); - if (calldepth > 0) - --calldepth; } else { int newpos = t->verdict; @@ -543,14 +535,9 @@ mark_source_chains(struct xt_table_info *newinfo, newpos); return 0; } - if (entry0 + newpos != ipt_next_entry(e) && - !(e->ip.flags & IPT_F_GOTO) && - ++calldepth > max_calldepth) - max_calldepth = calldepth; - /* This a jump; chase it. */ - duprintf("Jump rule %u -> %u, calldepth %d\n", - pos, newpos, calldepth); + duprintf("Jump rule %u -> %u\n", + pos, newpos); } else { /* ... this is a fallthru */ newpos = pos + e->next_offset; @@ -564,7 +551,6 @@ mark_source_chains(struct xt_table_info *newinfo, next: duprintf("Finished chain %u\n", hook); } - newinfo->stacksize = max_calldepth; return 1; } @@ -844,6 +830,9 @@ translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, if (ret != 0) return ret; ++i; + if (strcmp(ipt_get_target(iter)->u.user.name, + XT_ERROR_TARGET) == 0) + ++newinfo->stacksize; } if (i != repl->num_entries) { @@ -1759,6 +1748,9 @@ translate_compat_table(struct net *net, if (ret != 0) break; ++i; + if (strcmp(ipt_get_target(iter1)->u.user.name, + XT_ERROR_TARGET) == 0) + ++newinfo->stacksize; } if (ret) { /* diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index 4e21f80..0771991 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -455,15 +455,11 @@ ip6t_do_table(struct sk_buff *skb, } /* Figures out from what hook each rule can be called: returns 0 if - * there are loops. Puts hook bitmask in comefrom. - * - * Keeps track of largest call depth seen and stores it in newinfo->stacksize. - */ + there are loops. Puts hook bitmask in comefrom. */ static int -mark_source_chains(struct xt_table_info *newinfo, +mark_source_chains(const struct xt_table_info *newinfo, unsigned int valid_hooks, void *entry0) { - unsigned int calldepth, max_calldepth = 0; unsigned int hook; /* No recursion; use packet counter to save back ptrs (reset @@ -477,7 +473,6 @@ mark_source_chains(struct xt_table_info *newinfo, /* Set initial back pointer. */ e->counters.pcnt = pos; - calldepth = 0; for (;;) { const struct xt_standard_target *t @@ -539,8 +534,6 @@ mark_source_chains(struct xt_table_info *newinfo, (entry0 + pos + size); e->counters.pcnt = pos; pos += size; - if (calldepth > 0) - --calldepth; } else { int newpos = t->verdict; @@ -554,11 +547,6 @@ mark_source_chains(struct xt_table_info *newinfo, newpos); return 0; } - if (entry0 + newpos != ip6t_next_entry(e) && - !(e->ipv6.flags & IP6T_F_GOTO) && - ++calldepth > max_calldepth) - max_calldepth = calldepth; - /* This a jump; chase it. */ duprintf("Jump rule %u -> %u\n", pos, newpos); @@ -575,7 +563,6 @@ mark_source_chains(struct xt_table_info *newinfo, next: duprintf("Finished chain %u\n", hook); } - newinfo->stacksize = max_calldepth; return 1; } @@ -855,6 +842,9 @@ translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, if (ret != 0) return ret; ++i; + if (strcmp(ip6t_get_target(iter)->u.user.name, + XT_ERROR_TARGET) == 0) + ++newinfo->stacksize; } if (i != repl->num_entries) { @@ -1767,6 +1757,9 @@ translate_compat_table(struct net *net, if (ret != 0) break; ++i; + if (strcmp(ip6t_get_target(iter1)->u.user.name, + XT_ERROR_TARGET) == 0) + ++newinfo->stacksize; } if (ret) { /* -- cgit v0.10.2