lib: merge branch 'th/object-identical-fix'

thom311#248
heitbaum · Apr 17, 2020 · ab015e1 · ab015e1
2 parents 8637c70 + 36b0894
commit ab015e1
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Showing 3 changed files with 31 additions and 21 deletions.
diff --git a/include/netlink/utils.h b/include/netlink/utils.h
@@ -294,6 +294,13 @@ enum {
 	NL_CAPABILITY_VERSION_3_5_0 = 30,
 #define NL_CAPABILITY_VERSION_3_5_0 NL_CAPABILITY_VERSION_3_5_0
 
+	/**
+	 * nl_object_identical() can consider objects identical, if they both lack the same
+	 * set of ID attributes.
+	 */
+	NL_CAPABILITY_NL_OBJECT_IDENTICAL_PARTIAL = 31,
+#define NL_CAPABILITY_NL_OBJECT_IDENTICAL_PARTIAL NL_CAPABILITY_NL_OBJECT_IDENTICAL_PARTIAL
+
 	__NL_CAPABILITY_MAX,
 	NL_CAPABILITY_MAX = (__NL_CAPABILITY_MAX - 1),
 #define NL_CAPABILITY_MAX NL_CAPABILITY_MAX

diff --git a/lib/object.c b/lib/object.c
@@ -306,39 +306,42 @@ void nl_object_dump_buf(struct nl_object *obj, char *buf, size_t len)
  */
 int nl_object_identical(struct nl_object *a, struct nl_object *b)
 {
-	struct nl_object_ops *ops = obj_ops(a);
-	uint32_t req_attrs;
+	struct nl_object_ops *ops;
+	uint64_t req_attrs_a;
+	uint64_t req_attrs_b;
+
+	if (a == b)
+		return 1;
 
 	/* Both objects must be of same type */
+	ops = obj_ops(a);
 	if (ops != obj_ops(b))
 		return 0;
 
-	if (ops->oo_id_attrs_get) {
-		uint32_t req_attrs_a = ops->oo_id_attrs_get(a);
-		uint32_t req_attrs_b = ops->oo_id_attrs_get(b);
+	/* Can't judge unless we can compare */
+	if (ops->oo_compare == NULL)
+		return 0;
 
-		if (req_attrs_a != req_attrs_b)
-			return 0;
-		req_attrs = req_attrs_a;
+	if (ops->oo_id_attrs_get) {
+		req_attrs_a = ops->oo_id_attrs_get(a);
+		req_attrs_b = ops->oo_id_attrs_get(b);
 	} else if (ops->oo_id_attrs) {
-		req_attrs = ops->oo_id_attrs;
+		req_attrs_a = ops->oo_id_attrs;
+		req_attrs_b = req_attrs_a;
 	} else {
-		req_attrs = 0xFFFFFFFF;
+		req_attrs_a = UINT64_MAX;
+		req_attrs_b = req_attrs_a;
 	}
-	if (req_attrs == 0xFFFFFFFF)
-		req_attrs = a->ce_mask & b->ce_mask;
+
+	req_attrs_a &= a->ce_mask;
+	req_attrs_b &= b->ce_mask;
 
 	/* Both objects must provide all required attributes to uniquely
 	 * identify an object */
-	if ((a->ce_mask & req_attrs) != req_attrs ||
-	    (b->ce_mask & req_attrs) != req_attrs)
-		return 0;
-
-	/* Can't judge unless we can compare */
-	if (ops->oo_compare == NULL)
+	if (req_attrs_a != req_attrs_b)
 		return 0;
 
-	return !(ops->oo_compare(a, b, req_attrs, ID_COMPARISON));
+	return !(ops->oo_compare(a, b, req_attrs_a, ID_COMPARISON));
 }
 
 /**
@@ -360,7 +363,7 @@ uint64_t nl_object_diff64(struct nl_object *a, struct nl_object *b)
 	if (ops != obj_ops(b) || ops->oo_compare == NULL)
 		return UINT64_MAX;
 
-	return ops->oo_compare(a, b, ~0, 0);
+	return ops->oo_compare(a, b, UINT64_MAX, 0);
 }
 
 /**

diff --git a/lib/utils.c b/lib/utils.c
@@ -1217,7 +1217,7 @@ int nl_has_capability (int capability)
 			NL_CAPABILITY_VERSION_3_4_0,
 			NL_CAPABILITY_ROUTE_FIX_VLAN_SET_EGRESS_MAP,
 			NL_CAPABILITY_VERSION_3_5_0,
-			0,
+			NL_CAPABILITY_NL_OBJECT_IDENTICAL_PARTIAL,
 			0),
 		/* IMPORTANT: these capability numbers are intended to be universal and stable
 		 * for libnl3. Don't allocate new numbers on your own that differ from upstream