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

commit adc972c5b88829d38ede08b1069718661c7330ae upstream.

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 <fw@strlen.de>
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c
index 40e7445..32b7896 100644 (file)
--- a/net/netfilter/nf_tables_core.c
+++ b/net/netfilter/nf_tables_core.c
@@ -208,7 +208,8 @@ 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].rule  = rule;
                jumpstack[stackptr].rulenum = rulenum;