conntrack, expect: fix _cmp api with STRICT checking

Normal comparision succeeds when the _common_ attribute subset
have same values.

When STRICT matching is specified, the comparision should succeed only when
both objects have same attribute subset and attribute values match.

However, STRICT comparision often fails as an attribute missing in both
objects is erronously considered an error.

Signed-off-by: Florian Westphal <fw@strlen.de>

2 files changed, 11 insertions, 2 deletions

diff --git a/src/conntrack/compare.c b/src/conntrack/compare.c
index e282a24..97c25cb 100644
--- a/src/conntrack/compare.c
+++ b/src/conntrack/compare.c
@@ -17,8 +17,12 @@ static int __cmp(int attr,
 		 	    const struct nf_conntrack *ct2,
 			    unsigned int flags))
 {
-	if (test_bit(attr, ct1->head.set) && test_bit(attr, ct2->head.set)) {
+	int a = test_bit(attr, ct1->head.set);
+	int b = test_bit(attr, ct2->head.set);
+	if (a && b) {
 		return cmp(ct1, ct2, flags);
+	} else if (!a && !b) {
+		return 1;
 	} else if (flags & NFCT_CMP_MASK &&
 		   test_bit(attr, ct1->head.set)) {
 		return 0;
diff --git a/src/expect/compare.c b/src/expect/compare.c
index a524f4c..484d7b1 100644
--- a/src/expect/compare.c
+++ b/src/expect/compare.c
@@ -18,8 +18,13 @@ static int exp_cmp(int attr,
 			      const struct nf_expect *exp2,
 			      unsigned int flags))
 {
-	if (test_bit(attr, exp1->set) && test_bit(attr, exp2->set)) {
+	int a = test_bit(attr, exp1->set);
+	int b = test_bit(attr, exp2->set);
+
+	if (a && b) {
 		return cmp(exp1, exp2, flags);
+	} else if (!a && !b) {
+		return 1;
 	} else if (flags & NFCT_CMP_MASK &&
 		   test_bit(attr, exp1->set)) {
 		return 0;