1 files changed, 31 insertions, 6 deletions

diff --git a/net/netfilter/xt_owner.c b/net/netfilter/xt_owner.c
index 46686fb73784..0c101b25cacf 100644
--- a/net/netfilter/xt_owner.c
+++ b/net/netfilter/xt_owner.c
@@ -76,29 +76,54 @@ owner_mt(const struct sk_buff *skb, struct xt_action_param *par)
 		 */
 		return false;
 
-	filp = sk->sk_socket->file;
-	if (filp == NULL)
+	read_lock_bh(&sk->sk_callback_lock);
+	filp = sk->sk_socket ? sk->sk_socket->file : NULL;
+	if (filp == NULL) {
+		read_unlock_bh(&sk->sk_callback_lock);
 		return ((info->match ^ info->invert) &
 		       (XT_OWNER_UID | XT_OWNER_GID)) == 0;
+	}
 
 	if (info->match & XT_OWNER_UID) {
 		kuid_t uid_min = make_kuid(net->user_ns, info->uid_min);
 		kuid_t uid_max = make_kuid(net->user_ns, info->uid_max);
 		if ((uid_gte(filp->f_cred->fsuid, uid_min) &&
 		     uid_lte(filp->f_cred->fsuid, uid_max)) ^
-		    !(info->invert & XT_OWNER_UID))
+		    !(info->invert & XT_OWNER_UID)) {
+			read_unlock_bh(&sk->sk_callback_lock);
 			return false;
+		}
 	}
 
 	if (info->match & XT_OWNER_GID) {
+		unsigned int i, match = false;
 		kgid_t gid_min = make_kgid(net->user_ns, info->gid_min);
 		kgid_t gid_max = make_kgid(net->user_ns, info->gid_max);
-		if ((gid_gte(filp->f_cred->fsgid, gid_min) &&
-		     gid_lte(filp->f_cred->fsgid, gid_max)) ^
-		    !(info->invert & XT_OWNER_GID))
+		struct group_info *gi = filp->f_cred->group_info;
+
+		if (gid_gte(filp->f_cred->fsgid, gid_min) &&
+		    gid_lte(filp->f_cred->fsgid, gid_max))
+			match = true;
+
+		if (!match && (info->match & XT_OWNER_SUPPL_GROUPS) && gi) {
+			for (i = 0; i < gi->ngroups; ++i) {
+				kgid_t group = gi->gid[i];
+
+				if (gid_gte(group, gid_min) &&
+				    gid_lte(group, gid_max)) {
+					match = true;
+					break;
+				}
+			}
+		}
+
+		if (match ^ !(info->invert & XT_OWNER_GID)) {
+			read_unlock_bh(&sk->sk_callback_lock);
 			return false;
+		}
 	}
 
+	read_unlock_bh(&sk->sk_callback_lock);
 	return true;
 }