From bb6a6e8e091353770074608c1d1bfde0e20b8154 Mon Sep 17 00:00:00 2001 From: Liping Zhang Date: Sat, 22 Oct 2016 18:51:24 +0800 Subject: [PATCH] netfilter: nft_dynset: fix panic if NFT_SET_HASH is not enabled When CONFIG_NFT_SET_HASH is not enabled and I input the following rule: "nft add rule filter output flow table test {ip daddr counter }", kernel panic happened on my system: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [< (null)>] (null) [...] Call Trace: [] ? nft_dynset_eval+0x56/0x100 [nf_tables] [] nft_do_chain+0xfb/0x4e0 [nf_tables] [] ? nf_conntrack_tuple_taken+0x61/0x210 [nf_conntrack] [] ? get_unique_tuple+0x136/0x560 [nf_nat] [] ? __nf_ct_ext_add_length+0x111/0x130 [nf_conntrack] [] ? nf_nat_setup_info+0x87/0x3b0 [nf_nat] [] ? ipt_do_table+0x327/0x610 [] ? __nf_nat_alloc_null_binding+0x57/0x80 [nf_nat] [] nft_ipv4_output+0xaf/0xd0 [nf_tables_ipv4] [] nf_iterate+0x55/0x60 [] nf_hook_slow+0x73/0xd0 Because in rbtree type set, ops->update is not implemented. So just keep it simple, in such case, report -EOPNOTSUPP to the user space. Fixes: 22fe54d5fefc ("netfilter: nf_tables: add support for dynamic set updates") Signed-off-by: Liping Zhang Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_dynset.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c index 517f08767a3c..bfdb689664b0 100644 --- a/net/netfilter/nft_dynset.c +++ b/net/netfilter/nft_dynset.c @@ -139,6 +139,9 @@ static int nft_dynset_init(const struct nft_ctx *ctx, return PTR_ERR(set); } + if (set->ops->update == NULL) + return -EOPNOTSUPP; + if (set->flags & NFT_SET_CONSTANT) return -EBUSY; -- 2.39.5