修复高优先级安全和稳定性问题

1. app.py:
   - 添加user_semaphores_lock线程锁，修复get_user_semaphore竞态条件
   - 将9处裸except:改为except Exception:或具体异常类型

2. database.py:
   - 将3处裸except:改为except Exception:

3. email_service.py:
   - 添加_smtp_config_lock线程锁
   - 修复daily_sent计数竞态条件：获取配置时预增，失败时回退
   - _get_available_smtp_config和_get_next_available_smtp_config使用锁保护

🤖 Generated with Claude Code

app.py

@@ -162,6 +162,7 @@ IP_LOCK_DURATION = config.IP_LOCK_DURATION
 max_concurrent_per_account = config.MAX_CONCURRENT_PER_ACCOUNT
 max_concurrent_global = config.MAX_CONCURRENT_GLOBAL
 user_semaphores = {}  # {user_id: Semaphore}
+user_semaphores_lock = threading.Lock()  # 保护user_semaphores的线程锁
 global_semaphore = threading.Semaphore(max_concurrent_global)
 
 # 截图专用信号量:限制同时进行的截图任务数量(避免资源竞争)
@@ -1084,7 +1085,7 @@ def generate_captcha():
             try:
                 font = ImageFont.truetype(font_path, 42)
                 break
-            except:
+            except Exception:
                 continue
         if font is None:
             font = ImageFont.load_default()
@@ -1937,7 +1938,8 @@ def stop_account(account_id):
 
 
 def get_user_semaphore(user_id):
-    """获取或创建用户的信号量"""
+    """获取或创建用户的信号量（线程安全）"""
+    with user_semaphores_lock:
         if user_id not in user_semaphores:
             user_semaphores[user_id] = threading.Semaphore(max_concurrent_per_account)
         return user_semaphores[user_id]
@@ -4232,7 +4234,7 @@ def get_user_schedules_api():
     for s in schedules:
         try:
             s['account_ids'] = json.loads(s.get('account_ids', '[]') or '[]')
-        except:
+        except (json.JSONDecodeError, TypeError):
             s['account_ids'] = []
     return jsonify(schedules)
 
@@ -4282,7 +4284,7 @@ def get_schedule_detail_api(schedule_id):
     import json
     try:
         schedule['account_ids'] = json.loads(schedule.get('account_ids', '[]') or '[]')
-    except:
+    except (json.JSONDecodeError, TypeError):
         schedule['account_ids'] = []
     return jsonify(schedule)
 
@@ -4362,7 +4364,7 @@ def run_schedule_now_api(schedule_id):
 
     try:
         account_ids = json.loads(schedule.get('account_ids', '[]') or '[]')
-    except:
+    except (json.JSONDecodeError, TypeError):
         account_ids = []
 
     if not account_ids:
@@ -4544,7 +4546,7 @@ def cleanup_on_exit():
                 for user_id in user_accounts:
                     if account_id in user_accounts[user_id]:
                         user_accounts[user_id][account_id].should_stop = True
-        except:
+        except Exception:
             pass
 
     # 2. 等待所有线程完成（最多等待5秒）
@@ -4553,28 +4555,28 @@ def cleanup_on_exit():
         try:
             if thread and thread.is_alive():
                 thread.join(timeout=2)
-        except:
+        except Exception:
             pass
 
     # 3. 关闭浏览器工作线程池
     print("- 关闭浏览器线程池...")
     try:
         shutdown_browser_worker_pool()
-    except:
+    except Exception:
         pass
 
     # 3.5 关闭邮件队列
     print("- 关闭邮件队列...")
     try:
         email_service.shutdown_email_queue()
-    except:
+    except Exception:
         pass
 
     # 4. 关闭数据库连接池
     print("- 关闭数据库连接池...")
     try:
         db_pool._pool.close_all() if db_pool._pool else None
-    except:
+    except Exception:
         pass
 
     print("✓ 资源清理完成")

database.py

@@ -837,7 +837,7 @@ def update_user_email(user_id, email, verified=False):
         # 先检查email_verified字段是否存在，不存在则添加
         try:
             cursor.execute('SELECT email_verified FROM users LIMIT 1')
-        except:
+        except Exception:
             cursor.execute('ALTER TABLE users ADD COLUMN email_verified INTEGER DEFAULT 0')
             conn.commit()
 
@@ -857,7 +857,7 @@ def update_user_email_notify(user_id, enabled):
         # 先检查字段是否存在
         try:
             cursor.execute('SELECT email_notify_enabled FROM users LIMIT 1')
-        except:
+        except Exception:
             cursor.execute('ALTER TABLE users ADD COLUMN email_notify_enabled INTEGER DEFAULT 1')
             conn.commit()
 
@@ -881,7 +881,7 @@ def get_user_email_notify(user_id):
             if row is None:
                 return True
             return bool(row[0]) if row[0] is not None else True
-        except:
+        except Exception:
             return True  # 字段不存在时默认开启
 
 

email_service.py

@@ -78,6 +78,9 @@ QUEUE_MAX_SIZE = int(os.environ.get('EMAIL_QUEUE_MAX_SIZE', '100'))
 # 为安全起见，设置为10MB，超过则分批发送
 MAX_ATTACHMENT_SIZE = int(os.environ.get('EMAIL_MAX_ATTACHMENT_SIZE', str(10 * 1024 * 1024)))  # 10MB
 
+# SMTP配置获取锁（防止并发获取时竞态条件导致超过每日限额）
+_smtp_config_lock = threading.Lock()
+
 
 # ============ 数据库操作 ============
 
@@ -500,11 +503,13 @@ def set_primary_smtp_config(config_id: int) -> bool:
 
 def _get_available_smtp_config(failover: bool = True) -> Optional[Dict[str, Any]]:
     """
-    获取可用的SMTP配置
+    获取可用的SMTP配置（线程安全）
     优先级: 主配置 > 按priority排序的启用配置
+    使用锁保护防止并发获取时超过每日限额
     """
     today = datetime.now().strftime('%Y-%m-%d')
 
+    with _smtp_config_lock:  # 使用锁保护整个获取过程
         with db_pool.get_db() as conn:
             cursor = conn.cursor()
 
@@ -535,6 +540,15 @@ def _get_available_smtp_config(failover: bool = True) -> Optional[Dict[str, Any]
                 if daily_limit > 0 and daily_sent >= daily_limit:
                     continue  # 超过限额，跳过此配置
 
+                # 预增计数（在返回配置前先占用配额，防止并发超限）
+                # 如果发送失败，_update_smtp_stats会在失败时回退
+                cursor.execute("""
+                    UPDATE smtp_configs
+                    SET daily_sent = daily_sent + 1
+                    WHERE id = ?
+                """, (config_id,))
+                conn.commit()
+
                 # 解密密码
                 decrypted_password = decrypt_password(password) if password else ''
 
@@ -556,24 +570,30 @@ def _get_available_smtp_config(failover: bool = True) -> Optional[Dict[str, Any]
 
 
 def _update_smtp_stats(config_id: int, success: bool, error: str = ''):
-    """更新SMTP配置的统计信息"""
+    """更新SMTP配置的统计信息
+
+    注意：daily_sent已在_get_available_smtp_config中预增，
+    成功时只更新success_count，失<EFBC8C><E5A4B1>时需要回退daily_sent
+    """
     with db_pool.get_db() as conn:
         cursor = conn.cursor()
 
         if success:
+            # 成功：只更新成功计数（daily_sent已在获取配置时预增）
             cursor.execute("""
                 UPDATE smtp_configs
-                SET daily_sent = daily_sent + 1,
-                    success_count = success_count + 1,
+                SET success_count = success_count + 1,
                     last_success_at = CURRENT_TIMESTAMP,
                     last_error = '',
                     updated_at = CURRENT_TIMESTAMP
                 WHERE id = ?
             """, (config_id,))
         else:
+            # 失败：回退daily_sent并更新失败计数
             cursor.execute("""
                 UPDATE smtp_configs
-                SET fail_count = fail_count + 1,
+                SET daily_sent = MAX(0, daily_sent - 1),
+                    fail_count = fail_count + 1,
                     last_error = ?,
                     updated_at = CURRENT_TIMESTAMP
                 WHERE id = ?
@@ -765,9 +785,10 @@ def send_email(
 
 
 def _get_next_available_smtp_config(exclude_ids: List[int]) -> Optional[Dict[str, Any]]:
-    """获取下一个可用的SMTP配置（排除已尝试的）"""
+    """获取下一个可用的SMTP配置（排除已尝试的，线程安全）"""
     today = datetime.now().strftime('%Y-%m-%d')
 
+    with _smtp_config_lock:  # 使用锁保护
         with db_pool.get_db() as conn:
             cursor = conn.cursor()
 
@@ -790,7 +811,16 @@ def _get_next_available_smtp_config(exclude_ids: List[int]) -> Optional[Dict[str
 
             # 检查每日限额
             if daily_limit > 0 and daily_sent >= daily_limit:
-            return _get_next_available_smtp_config(exclude_ids + [config_id])
+                # 递归调用在锁外进行，避免死锁
+                pass
+            else:
+                # 预增计数
+                cursor.execute("""
+                    UPDATE smtp_configs
+                    SET daily_sent = daily_sent + 1
+                    WHERE id = ?
+                """, (config_id,))
+                conn.commit()
 
                 return {
                     'id': config_id,
@@ -806,6 +836,9 @@ def _get_next_available_smtp_config(exclude_ids: List[int]) -> Optional[Dict[str
                     'is_primary': bool(is_primary)
                 }
 
+    # 递归调用在锁外进行
+    return _get_next_available_smtp_config(exclude_ids + [config_id])
+
 
 def test_smtp_config(config_id: int, test_email: str) -> Dict[str, Any]:
     """测试SMTP配置"""