samba/CVE-2020-14303-1.patch

66 lines
2.2 KiB
Diff

From 11034ea33fca9b8a1c2e14480e70069b55fca6a2 Mon Sep 17 00:00:00 2001
From: Andrew Bartlett <abartlet@samba.org>
Date: Thu, 25 Jun 2020 11:59:54 +1200
Subject: [PATCH 19/22] CVE-2020-14303 Ensure an empty packet will not DoS the
NBT server
Signed-off-by: Andrew Bartlett <abartlet@samba.org>
---
python/samba/tests/dns_packet.py | 19 +++++++++++++++++++
selftest/knownfail.d/empty-nbt | 1 +
2 files changed, 20 insertions(+)
create mode 100644 selftest/knownfail.d/empty-nbt
diff --git a/python/samba/tests/dns_packet.py b/python/samba/tests/dns_packet.py
index c4f843eb613..ae7bcb3ad8c 100644
--- a/python/samba/tests/dns_packet.py
+++ b/python/samba/tests/dns_packet.py
@@ -156,6 +156,19 @@ class TestDnsPacketBase(TestCase):
rcode = self.decode_reply(data)['rcode']
return expected_rcode == rcode
+ def _test_empty_packet(self):
+
+ packet = b""
+ s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+ s.sendto(packet, self.server)
+ s.close()
+
+ # It is reasonable not to reply to an empty packet
+ # but it is not reasonable to render the server
+ # unresponsive.
+ ok = self._known_good_query()
+ self.assertTrue(ok, f"the server is unresponsive")
+
class TestDnsPackets(TestDnsPacketBase):
server = (SERVER, 53)
@@ -174,6 +187,9 @@ class TestDnsPackets(TestDnsPacketBase):
label = b'x.' * 31 + b'x'
self._test_many_repeated_components(label, 127)
+ def test_empty_packet(self):
+ self._test_empty_packet()
+
class TestNbtPackets(TestDnsPacketBase):
server = (SERVER, 137)
@@ -209,3 +225,6 @@ class TestNbtPackets(TestDnsPacketBase):
def test_127_half_dotty_components(self):
label = b'x.' * 31 + b'x'
self._test_many_repeated_components(label, 127)
+
+ def test_empty_packet(self):
+ self._test_empty_packet()
diff --git a/selftest/knownfail.d/empty-nbt b/selftest/knownfail.d/empty-nbt
new file mode 100644
index 00000000000..e4bcccab4e5
--- /dev/null
+++ b/selftest/knownfail.d/empty-nbt
@@ -0,0 +1 @@
+^samba.tests.dns_packet.samba.tests.dns_packet.TestNbtPackets.test_empty_packet
\ No newline at end of file
--
2.17.1