[PATCH nf-next v1] netfilter: nft_ct: fix null pointer in ct expectations support

[Stéphane Veyret]

As discovered by Coverity, nf_ct_helper_ext_add may return null, which must 
then be checked.
---
 net/netfilter/nft_ct.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c
index 06b52c894573..dd731d5d9fb5 100644
--- a/net/netfilter/nft_ct.c
+++ b/net/netfilter/nft_ct.c
@@ -1232,6 +1232,10 @@ static void nft_ct_expect_obj_eval(struct nft_object 
*obj,
        help = nfct_help(ct);
        if (!help)
                help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
+       if (!help) {
+               regs->verdict.code = NF_DROP;
+               return;
+       }
 
        if (help->expecting[NF_CT_EXPECT_CLASS_DEFAULT] >= priv->size) {
                regs->verdict.code = NFT_BREAK;
@@ -1241,7 +1245,7 @@ static void nft_ct_expect_obj_eval(struct nft_object *obj,
                l3num = nf_ct_l3num(ct);
 
        exp = nf_ct_expect_alloc(ct);
-       if (exp == NULL) {
+       if (!exp) {
                regs->verdict.code = NF_DROP;
                return;
        }
-- 
2.21.0