E-01修复：poll超长守卫前置st.size根治死码，save输出上限收紧4096，写盘闸拦截与自检留痕

2026-09-22 01:28:10 +08:00
parent c3f424abc0
commit c29b728153
3 changed files with 120 additions and 20 deletions
@@ -302,6 +302,65 @@ static int run_cfgtest(void)
        }
    }
    printf("[cfgtest] OK surgical save (comment kept, value intact)\n");
+
+    /* E-01 场景 1：伪造超长文件（> CFG_FILE_MAX_LEN）→ poll 必须判损坏
+     * （与 load/MCU 同一契约）：RAM 回工厂默认 + 文件重建为出厂模板，
+     * 而非截断解析残留 10.0.0.1（修复前死码走的是截断分支） */
+    {
+        uint8_t big[CFG_FILE_MAX_LEN + 64u];
+        cfg_file_stat_t st_chk;
+
+        (void)memset(big, ';', sizeof(big));  /* 纯注释：内容无关，尺寸超即触发 */
+        if (cfg_store_write_atomic(cfg_store_config_path(), big, sizeof(big)) != 0) {
+            printf("[cfgtest] FAIL forge oversized write\n");
+            return 1;
+        }
+        cfg_file_poll();             /* 检出变更（沉降计数 1） */
+        cfg_file_poll();             /* 沉降完成 → 损坏分支：工厂默认 + 重建模板 */
+
+        if (cfg_store_stat(cfg_store_config_path(), &st_chk) != 0 ||
+                st_chk.size == 0u || st_chk.size > CFG_FILE_MAX_LEN) {
+            printf("[cfgtest] FAIL oversized file not rebuilt (size=%lu)\n",
+                   (unsigned long)st_chk.size);
+            return 1;
+        }
+        p_cfg = net_cfg_get();
+        if (p_cfg->ip[0] != 192u || p_cfg->ip[1] != 168u ||
+                p_cfg->ip[2] != 1u || p_cfg->ip[3] != 100u) {
+            printf("[cfgtest] FAIL ip not factory after oversized: %u.%u.%u.%u\n",
+                   (unsigned)p_cfg->ip[0], (unsigned)p_cfg->ip[1],
+                   (unsigned)p_cfg->ip[2], (unsigned)p_cfg->ip[3]);
+            return 1;
+        }
+    }
+    printf("[cfgtest] OK oversized file rebuilt to factory template\n");
+
+    /* E-01 场景 2：save 拒写"雷"文件——伪造合法界内纯注释文件（4000B，无
+     * [network] 段），外科手术保存文末补写受管段 → 输出必然超
+     * CFG_FILE_MAX_LEN：必须拒绝（net_cfg_save 返 -1）且原文件不动；
+     * 修复前此处会成功写出 ~4200B 超长文件 = 下次开机被销毁的雷 */
+    {
+        uint8_t pad[4000u];
+        cfg_file_stat_t st_chk;
+
+        (void)memset(pad, ';', sizeof(pad));
+        if (cfg_store_write_atomic(cfg_store_config_path(), pad, sizeof(pad)) != 0) {
+            printf("[cfgtest] FAIL forge padding write\n");
+            return 1;
+        }
+        if (net_cfg_save() == 0) {
+            printf("[cfgtest] FAIL oversized document was written (landmine)\n");
+            return 1;
+        }
+        (void)cfg_store_stat(cfg_store_config_path(), &st_chk);
+        if (st_chk.size != 4000u) {
+            printf("[cfgtest] FAIL file modified by rejected save (size=%lu)\n",
+                   (unsigned long)st_chk.size);
+            return 1;
+        }
+    }
+    printf("[cfgtest] OK save rejected oversized document (file untouched)\n");
+
    printf("[cfgtest] PASS\n");
    return 0;
 }