From 7e91fee7bfd6015d4a87c4c1f81818e19eaaa6d5 Mon Sep 17 00:00:00 2001
From: ChaosAttractor <lostattractor@gmail.com>
Date: Tue, 24 Dec 2024 01:23:24 +0800
Subject: [PATCH] fix: must_rules causes match_set modification

---
 control/kern/tproxy.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/control/kern/tproxy.c b/control/kern/tproxy.c
index 88fc56f17..8b02dbea2 100644
--- a/control/kern/tproxy.c
+++ b/control/kern/tproxy.c
@@ -829,15 +829,14 @@ static int route_loop_cb(__u32 index, void *data)
 				     OUTBOUND_MUST_RULES)) {
 				ctx->isdns_must_goodsubrule_badrule |= 0b100;
 			} else {
-				if (ctx->isdns_must_goodsubrule_badrule & 0b100)
-					match_set->must = true;
-				if (!match_set->must &&
+				bool must = ctx->isdns_must_goodsubrule_badrule & 0b100 || match_set->must;
+				if (!must &&
 				    (ctx->isdns_must_goodsubrule_badrule &
 				     0b1000)) {
 					ctx->result =
 						(__s64)OUTBOUND_CONTROL_PLANE_ROUTING |
 						((__s64)match_set->mark << 8) |
-						((__s64)match_set->must << 40);
+						((__s64)must << 40);
 #ifdef __DEBUG_ROUTING
 					bpf_printk(
 						"OUTBOUND_CONTROL_PLANE_ROUTING: %ld",
@@ -847,7 +846,7 @@ static int route_loop_cb(__u32 index, void *data)
 				}
 				ctx->result = (__s64)match_set->outbound |
 					      ((__s64)match_set->mark << 8) |
-					      ((__s64)match_set->must << 40);
+					      ((__s64)must << 40);
 #ifdef __DEBUG_ROUTING
 				bpf_printk("outbound %u: %ld",
 					   match_set->outbound, ctx->result);