commit 073eca39a55b86ec7dd7a437ac0c910751a60ace
author Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> Sun May 20 08:40:10 2018 -0700
committer GitHub <noreply@github.com> Sun May 20 08:40:10 2018 -0700
tree a74e06ced0cea7ee2af7c6e68c038253b210bdb5
parent 736e3b32194b52b1779ce88a2c13862f0f913a7a

bpo-33542: Ignore DUID in uuid.get_node on Windows. (GH-6922)


uuid._ipconfig_getnode did not validate the maximum length of the value,
so long as the value had the same type of formatting as a MAC address.
This let it select DUIDs as MAC addresses. It now requires an exact
length match.
(cherry picked from commit c66c342cb42ab8a88884527ddfe3a5086bc06316)

Co-authored-by: CtrlZvi <viz+github@flippedperspective.com>

Lib/uuid.py

diff --git a/Lib/uuid.py b/Lib/uuid.py
index 9cb73e8..6638321 100644
--- a/Lib/uuid.py
+++ b/Lib/uuid.py
@@ -488,7 +488,7 @@
         with proc:
             for line in proc.stdout:
                 value = line.split(':')[-1].strip().lower()
-                if re.match('([0-9a-f][0-9a-f]-){5}[0-9a-f][0-9a-f]', value):
+                if re.fullmatch('(?:[0-9a-f][0-9a-f]-){5}[0-9a-f][0-9a-f]', value):
                     mac = int(value.replace('-', ''), 16)
                     if _is_universal(mac):
                         return mac