Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf

Pablo Neira Ayuso says:

====================
Netfilter/nftables fixes for net

The following patchset contains nftables fixes for your net tree, they
are:

1) Fix crash when using the goto action in a rule by making sure that
   we always fall back on the base chain. Otherwise, this may try to
   access the counter memory area of non-base chains, which does not
   exists.

2) Fix several aspects of the rule tracing that are currently broken:

   * Reset rule number counter after goto/jump action, otherwise the
     tracing reports a bogus rule number.
   * Fix tracing of the goto action.
   * Fix bogus rule number counter after goto.
   * Fix missing return trace after finishing the walk through the
     non-base chain.
   * Fix missing trace when matching non-terminal rule.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 23 insertions, 26 deletions

diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c
index 804105391b9a..345acfb1720b 100644
--- a/net/netfilter/nf_tables_core.c
+++ b/net/netfilter/nf_tables_core.c
@@ -66,20 +66,6 @@ struct nft_jumpstack {
         int                     rulenum;
 };
 
-static inline void
-nft_chain_stats(const struct nft_chain *this, const struct nft_pktinfo *pkt,
-                struct nft_jumpstack *jumpstack, unsigned int stackptr)
-{
-        struct nft_stats __percpu *stats;
-        const struct nft_chain *chain = stackptr ? jumpstack[0].chain : this;
-
-        rcu_read_lock_bh();
-        stats = rcu_dereference(nft_base_chain(chain)->stats);
-        __this_cpu_inc(stats->pkts);
-        __this_cpu_add(stats->bytes, pkt->skb->len);
-        rcu_read_unlock_bh();
-}
-
 enum nft_trace {
         NFT_TRACE_RULE,
         NFT_TRACE_RETURN,
@@ -117,13 +103,14 @@ static void nft_trace_packet(const struct nft_pktinfo *pkt,
 unsigned int
 nft_do_chain(struct nft_pktinfo *pkt, const struct nf_hook_ops *ops)
 {
-        const struct nft_chain *chain = ops->priv;
+        const struct nft_chain *chain = ops->priv, *basechain = chain;
         const struct nft_rule *rule;
         const struct nft_expr *expr, *last;
         struct nft_data data[NFT_REG_MAX + 1];
         unsigned int stackptr = 0;
         struct nft_jumpstack jumpstack[NFT_JUMP_STACK_SIZE];
-        int rulenum = 0;
+        struct nft_stats __percpu *stats;
+        int rulenum;
         /*
          * Cache cursor to avoid problems in case that the cursor is updated
          * while traversing the ruleset.
@@ -131,6 +118,7 @@ nft_do_chain(struct nft_pktinfo *pkt, const struct nf_hook_ops *ops)
         unsigned int gencursor = ACCESS_ONCE(chain->net->nft.gencursor);
 
 do_chain:
+        rulenum = 0;
         rule = list_entry(&chain->rules, struct nft_rule, list);
 next_rule:
         data[NFT_REG_VERDICT].verdict = NFT_CONTINUE;
@@ -156,8 +144,10 @@ next_rule:
                 switch (data[NFT_REG_VERDICT].verdict) {
                 case NFT_BREAK:
                         data[NFT_REG_VERDICT].verdict = NFT_CONTINUE;
-                        /* fall through */
+                        continue;
                 case NFT_CONTINUE:
+                        if (unlikely(pkt->skb->nf_trace))
+                                nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RULE);
                         continue;
                 }
                 break;
@@ -183,37 +173,44 @@ next_rule:
                 jumpstack[stackptr].rule  = rule;
                 jumpstack[stackptr].rulenum = rulenum;
                 stackptr++;
-                /* fall through */
+                chain = data[NFT_REG_VERDICT].chain;
+                goto do_chain;
         case NFT_GOTO:
+                if (unlikely(pkt->skb->nf_trace))
+                        nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RULE);
+
                 chain = data[NFT_REG_VERDICT].chain;
                 goto do_chain;
         case NFT_RETURN:
                 if (unlikely(pkt->skb->nf_trace))
                         nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RETURN);
-
-                /* fall through */
+                break;
         case NFT_CONTINUE:
+                if (unlikely(pkt->skb->nf_trace && !(chain->flags & NFT_BASE_CHAIN)))
+                        nft_trace_packet(pkt, chain, ++rulenum, NFT_TRACE_RETURN);
                 break;
         default:
                 WARN_ON(1);
         }
 
         if (stackptr > 0) {
-                if (unlikely(pkt->skb->nf_trace))
-                        nft_trace_packet(pkt, chain, ++rulenum, NFT_TRACE_RETURN);
-
                 stackptr--;
                 chain = jumpstack[stackptr].chain;
                 rule  = jumpstack[stackptr].rule;
                 rulenum = jumpstack[stackptr].rulenum;
                 goto next_rule;
         }
-        nft_chain_stats(chain, pkt, jumpstack, stackptr);
 
         if (unlikely(pkt->skb->nf_trace))
-                nft_trace_packet(pkt, chain, ++rulenum, NFT_TRACE_POLICY);
+                nft_trace_packet(pkt, basechain, -1, NFT_TRACE_POLICY);
+
+        rcu_read_lock_bh();
+        stats = rcu_dereference(nft_base_chain(basechain)->stats);
+        __this_cpu_inc(stats->pkts);
+        __this_cpu_add(stats->bytes, pkt->skb->len);
+        rcu_read_unlock_bh();
 
-        return nft_base_chain(chain)->policy;
+        return nft_base_chain(basechain)->policy;
 }
 EXPORT_SYMBOL_GPL(nft_do_chain);