From: Pedro Schlickmann Mendes <windowsxpedro@gmail.com>
Date: Thu, 20 Jul 2023 12:59:59 +0100
Subject: Fixed URLValidator crash in some edge cases

Origin: upstream, https://github.com/django/django/commit/e8b4feddc34ffe5759ec21da8fa027e86e653f1c
Bug: https://code.djangoproject.com/ticket/33367
Last-Update: 2021-12-15
---
 django/core/validators.py | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/django/core/validators.py b/django/core/validators.py
index 731ccf2d4690..6b28eef08dd2 100644
--- a/django/core/validators.py
+++ b/django/core/validators.py
@@ -110,15 +110,16 @@ class URLValidator(RegexValidator):
             raise ValidationError(self.message, code=self.code, params={'value': value})
 
         # Then check full URL
+        try:
+            splitted_url = urlsplit(value)
+        except ValueError:
+            raise ValidationError(self.message, code=self.code, params={'value': value})
         try:
             super().__call__(value)
         except ValidationError as e:
             # Trivial case failed. Try for possible IDN domain
             if value:
-                try:
-                    scheme, netloc, path, query, fragment = urlsplit(value)
-                except ValueError:  # for example, "Invalid IPv6 URL"
-                    raise ValidationError(self.message, code=self.code, params={'value': value})
+                scheme, netloc, path, query, fragment = splitted_url
                 try:
                     netloc = punycode(netloc)  # IDN -> ACE
                 except UnicodeError:  # invalid domain part
@@ -129,7 +130,7 @@ class URLValidator(RegexValidator):
                 raise
         else:
             # Now verify IPv6 in the netloc part
-            host_match = re.search(r'^\[(.+)\](?::\d{2,5})?$', urlsplit(value).netloc)
+            host_match = re.search(r'^\[(.+)\](?::\d{2,5})?$', splitted_url.netloc)
             if host_match:
                 potential_ip = host_match[1]
                 try:
@@ -141,7 +142,7 @@ class URLValidator(RegexValidator):
         # section 3.1. It's defined to be 255 bytes or less, but this includes
         # one byte for the length of the name and one byte for the trailing dot
         # that's used to indicate absolute names in DNS.
-        if len(urlsplit(value).hostname) > 253:
+        if splitted_url.hostname is None or len(splitted_url.hostname) > 253:
             raise ValidationError(self.message, code=self.code, params={'value': value})