Issue #29061: secrets.randbelow() would hang with a negative input
diff --git a/Lib/secrets.py b/Lib/secrets.py
index 27fa450..1304342 100644
--- a/Lib/secrets.py
+++ b/Lib/secrets.py
@@ -26,6 +26,8 @@
def randbelow(exclusive_upper_bound):
"""Return a random int in the range [0, n)."""
+ if exclusive_upper_bound <= 0:
+ raise ValueError("Upper bound must be positive.")
return _sysrand._randbelow(exclusive_upper_bound)
DEFAULT_ENTROPY = 32 # number of bytes to return by default
diff --git a/Lib/test/test_secrets.py b/Lib/test/test_secrets.py
index 4c65cf0..d31d07e 100644
--- a/Lib/test/test_secrets.py
+++ b/Lib/test/test_secrets.py
@@ -70,6 +70,7 @@
for i in range(2, 10):
self.assertIn(secrets.randbelow(i), range(i))
self.assertRaises(ValueError, secrets.randbelow, 0)
+ self.assertRaises(ValueError, secrets.randbelow, -1)
class Token_Tests(unittest.TestCase):
diff --git a/Misc/ACKS b/Misc/ACKS
index 5faed18..1c3f573 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -369,6 +369,7 @@
Josip Djolonga
Walter Dörwald
Jaromir Dolecek
+Brendan Donegan
Ismail Donmez
Robert Donohue
Marcos Donolo
diff --git a/Misc/NEWS b/Misc/NEWS
index 3436c0a..f3c6e9e 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -43,6 +43,9 @@
- Issue #29085: Allow random.Random.seed() to use high quality OS randomness
rather than the pid and time.
+- Issue #29061: Fixed bug in secrets.randbelow() which would hang when given
+ a negative input. Patch by Brendan Donegan.
+
- Issue #29079: Prevent infinite loop in pathlib.resolve() on Windows
- Issue #13051: Fixed recursion errors in large or resized