From: Florian Westphal <fw@xxxxxxxxx>
else we will oops (null deref) when the attributes aren't present.
Also add back the EOPNOTSUPP in case MARK filtering is requested but
kernel doesn't support it.
Fixes: 59c08c69c2788 ("netfilter: ctnetlink: Support L3 protocol-filter on flush")
Reported-by: syzbot+e45eda8eda6e93a03959@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
net/netfilter/nf_conntrack_netlink.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 099a450e26be..4ae8e528943a 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -832,6 +832,11 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
{
struct ctnetlink_filter *filter;
+#ifndef CONFIG_NF_CONNTRACK_MARK
+ if (cda[CTA_MARK] && cda[CTA_MARK_MASK])
+ return ERR_PTR(-EOPNOTSUPP);
+#endif
+
filter = kzalloc(sizeof(*filter), GFP_KERNEL);
if (filter == NULL)
return ERR_PTR(-ENOMEM);
@@ -839,8 +844,10 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
filter->family = family;
#ifdef CONFIG_NF_CONNTRACK_MARK
- filter->mark.val = ntohl(nla_get_be32(cda[CTA_MARK]));
- filter->mark.mask = ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
+ if (cda[CTA_MARK] && cda[CTA_MARK_MASK]) {
+ filter->mark.val = ntohl(nla_get_be32(cda[CTA_MARK]));
+ filter->mark.mask = ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
+ }
#endif
return filter;
}
--
2.11.0
