[PATCH nft] optimize: do not merge unsupported statement expressions

[Pablo Neira Ayuso <pablo@netfilter.org>]

Only value, range, prefix, set and list are supported at this stage.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 src/optimize.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/src/optimize.c b/src/optimize.c
index c8bdccf7b610..b4035d0a96fc 100644
--- a/src/optimize.c
+++ b/src/optimize.c
@@ -91,6 +91,22 @@ static bool __expr_cmp(const struct expr *expr_a, const struct expr *expr_b)
 	return true;
 }
 
+static bool stmt_expr_supported(const struct expr *expr)
+{
+	switch (expr->right->etype) {
+	case EXPR_VALUE:
+	case EXPR_RANGE:
+	case EXPR_PREFIX:
+	case EXPR_SET:
+	case EXPR_LIST:
+		return true;
+	default:
+		break;
+	}
+
+	return false;
+}
+
 static bool __stmt_type_eq(const struct stmt *stmt_a, const struct stmt *stmt_b)
 {
 	struct expr *expr_a, *expr_b;
@@ -103,6 +119,10 @@ static bool __stmt_type_eq(const struct stmt *stmt_a, const struct stmt *stmt_b)
 		expr_a = stmt_a->expr;
 		expr_b = stmt_b->expr;
 
+		if (!stmt_expr_supported(expr_a) ||
+		    !stmt_expr_supported(expr_b))
+			return false;
+
 		return __expr_cmp(expr_a->left, expr_b->left);
 	case STMT_COUNTER:
 	case STMT_NOTRACK:
-- 
2.30.2