netfilter: nf_tables: use WARN_ON_ONCE instead of BUG_ON in nft_do_chain()

When depth of chain is bigger than NFT_JUMP_STACK_SIZE, the nft_do_chain
crashes. But there is no need to crash hard here.

Suggested-by: Florian Westphal <[email protected]>
Signed-off-by: Taehee Yoo <[email protected]>
Acked-by: Florian Westphal <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>

diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c
index deff10adef9c4b97bf60f0f5d18d46e33fcfd348..8de912ca53d3bfb1b2a924cbeb655d8e4d4ebd3a 100644 (file)
--- a/net/netfilter/nf_tables_core.c
+++ b/net/netfilter/nf_tables_core.c
@@ -183,7 +183,8 @@ next_rule:
 
        switch (regs.verdict.code) {
        case NFT_JUMP:
-               BUG_ON(stackptr >= NFT_JUMP_STACK_SIZE);
+               if (WARN_ON_ONCE(stackptr >= NFT_JUMP_STACK_SIZE))
+                       return NF_DROP;
                jumpstack[stackptr].chain = chain;
                jumpstack[stackptr].rules = rules + 1;
                stackptr++;