Sanitize port in `addpeeraddress()`

- Ensures port sanitization in `addpeeraddress()`
- Adds test to check for invalid port values

src/rpc/net.cpp

@@ -932,7 +932,7 @@ static RPCHelpMan addpeeraddress()
     }
 
     const std::string& addr_string{request.params[0].get_str()};
-    const uint16_t port{static_cast<uint16_t>(request.params[1].get_int())};
+    const auto port{request.params[1].getInt<uint16_t>()};
     const bool tried{request.params[2].isTrue()};
 
     UniValue obj(UniValue::VOBJ);

test/functional/rpc_net.py

@@ -257,6 +257,10 @@ class NetTest(BitcoinTestFramework):
         assert_equal(node.addpeeraddress(address="", port=8333), {"success": False})
         assert_equal(node.getnodeaddresses(count=0), [])
 
+        self.log.debug("Test that adding an address with invalid port fails")
+        assert_raises_rpc_error(-1, "JSON integer out of range", self.nodes[0].addpeeraddress, address="1.2.3.4", port=-1)
+        assert_raises_rpc_error(-1, "JSON integer out of range", self.nodes[0].addpeeraddress,address="1.2.3.4", port=65536)
+
         self.log.debug("Test that adding a valid address to the tried table succeeds")
         assert_equal(node.addpeeraddress(address="1.2.3.4", tried=True, port=8333), {"success": True})
         with node.assert_debug_log(expected_msgs=["CheckAddrman: new 0, tried 1, total 1 started"]):