From 9e43acf2f31e67a976475c2c9f8674dd27571cc6 Mon Sep 17 00:00:00 2001 From: Georg Brandl Date: Mon, 4 Jul 2005 17:16:07 +0000 Subject: bug #1177468: don't cache /dev/urandom file descriptor in os.urandom --- Lib/os.py | 12 ++++-------- Misc/NEWS | 3 +++ 2 files changed, 7 insertions(+), 8 deletions(-) diff --git a/Lib/os.py b/Lib/os.py index 5824609..bf1b086 100644 --- a/Lib/os.py +++ b/Lib/os.py @@ -715,22 +715,18 @@ except NameError: # statvfs_result may not exist pass if not _exists("urandom"): - _urandomfd = None def urandom(n): """urandom(n) -> str Return a string of n random bytes suitable for cryptographic use. """ - global _urandomfd - if _urandomfd is None: - try: - _urandomfd = open("/dev/urandom", O_RDONLY) - except: - _urandomfd = NotImplementedError - if _urandomfd is NotImplementedError: + try: + _urandomfd = open("/dev/urandom", O_RDONLY) + except: raise NotImplementedError("/dev/urandom (or equivalent) not found") bytes = "" while len(bytes) < n: bytes += read(_urandomfd, n - len(bytes)) + close(_urandomfd) return bytes diff --git a/Misc/NEWS b/Misc/NEWS index 8d86efd..bcc696a 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -150,6 +150,9 @@ Extension Modules Library ------- +- Bug #1177468: Don't cache the /dev/urandom file descriptor for os.urandom, + as this can cause problems with apps closing all file descriptors. + - Bug #839151: Fix an attempt to access sys.argv in the warnings module though this can be missing in embedded interpreters -- cgit v0.12