nftables/SOURCES/0157-evaluate-optimize-zero-length-range.patch
2026-08-26 08:03:54 -04:00

67 lines
2.0 KiB
Diff

From 1a384d6d3f411695375ee5d04a32cc317a295b30 Mon Sep 17 00:00:00 2001
From: Phil Sutter <psutter@redhat.com>
Date: Fri, 17 Jul 2026 11:11:00 +0200
Subject: [PATCH] evaluate: optimize zero length range
JIRA: https://issues.redhat.com/browse/RHEL-190549
Upstream Status: nftables commit deda274293f80f9718de4cbb416bd2b2bf296709
commit deda274293f80f9718de4cbb416bd2b2bf296709
Author: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Sat Feb 22 00:32:11 2025 +0100
evaluate: optimize zero length range
A rule like the following:
... tcp dport 22-22 ...
results in a range expression to match from 22 to 22.
Simplify to singleton value so a cmp is used instead.
This optimization already exists in set elements which might explain
this overlook.
Fixes: 7a6e16040d65 ("evaluate: allow for zero length ranges")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Phil Sutter <psutter@redhat.com>
---
src/evaluate.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/src/evaluate.c b/src/evaluate.c
index 2cc17c3..7059108 100644
--- a/src/evaluate.c
+++ b/src/evaluate.c
@@ -1285,12 +1285,12 @@ static int __expr_evaluate_range(struct eval_ctx *ctx, struct expr **expr)
return 0;
}
-static int expr_evaluate_range(struct eval_ctx *ctx, struct expr **expr)
+static int expr_evaluate_range(struct eval_ctx *ctx, struct expr **exprp)
{
- struct expr *range = *expr, *left, *right;
+ struct expr *range = *exprp, *left, *right;
int rc;
- rc = __expr_evaluate_range(ctx, expr);
+ rc = __expr_evaluate_range(ctx, exprp);
if (rc)
return rc;
@@ -1300,6 +1300,12 @@ static int expr_evaluate_range(struct eval_ctx *ctx, struct expr **expr)
if (mpz_cmp(left->value, right->value) > 0)
return expr_error(ctx->msgs, range, "Range negative size");
+ if (mpz_cmp(left->value, right->value) == 0) {
+ *exprp = expr_get(left);
+ expr_free(range);
+ return 0;
+ }
+
datatype_set(range, left->dtype);
range->flags |= EXPR_F_CONSTANT;
return 0;