[CVE-2020-14422] bpo-41004: Resolve hash collisions for IPv4Interface and IPv6Interfa...

The __hash__() methods of classes IPv4Interface and IPv6Interface had issue
of generating constant hash values of 32 and 128 respectively causing hash collisions.
The fix uses the hash() function to generate hash values for the objects
instead of XOR operation

Change-Id: Iedba34943247152526befe55ee13a297df2da216
Signed-off-by: DongHun Kwak <dh0128.kwak@samsung.com>

diff --git a/Lib/ipaddress.py b/Lib/ipaddress.py
index cc9ae7118d67914d40153d434821aac0e9d19875..4193e32c66324f818172cfae7b7d3f9578130e20 100644 (file)
--- a/Lib/ipaddress.py
+++ b/Lib/ipaddress.py
@@ -1435,7 +1435,7 @@ class IPv4Interface(IPv4Address):
             return False
 
     def __hash__(self):
-        return self._ip ^ self._prefixlen ^ int(self.network.network_address)
+        return hash((self._ip, self._prefixlen, int(self.network.network_address)))
 
     __reduce__ = _IPAddressBase.__reduce__
 
@@ -2109,7 +2109,7 @@ class IPv6Interface(IPv6Address):
             return False
 
     def __hash__(self):
-        return self._ip ^ self._prefixlen ^ int(self.network.network_address)
+        return hash((self._ip, self._prefixlen, int(self.network.network_address)))
 
     __reduce__ = _IPAddressBase.__reduce__