Bugs item #1117601, was opened at 2005-02-06 16:57 Message generated for change (Comment added) made by josiahcarlson You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1117601&group_id=5470
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Python Library Group: Platform-specific Status: Open Resolution: None Priority: 5 Submitted By: Stephen Bennett (sbennett) Assigned to: Nobody/Anonymous (nobody) Summary: os.path.exists returns false negatives in MAC environments. Initial Comment: In Mandatory Access Control environments (such as SELinux), it's quite possible for stat to fail with permission denied. In this case, os.path.exists will return False incorrectly. The simple(ish) fix is to check for an access denied error (which would indicate present, but not readable) when using stat to check for existence of files. ---------------------------------------------------------------------- Comment By: Josiah Carlson (josiahcarlson) Date: 2005-05-31 00:09 Message: Logged In: YES user_id=341410 I believe Terry was curious about something like os.path.exists("/etc/shadow/abc123") vs `ls -l /etc/shadow/abc123`. If not, I know I am curious, and I believe it may help with a corner case. ---------------------------------------------------------------------- Comment By: Stephen Bennett (sbennett) Date: 2005-02-16 14:46 Message: Logged In: YES user_id=817465 As far as I know (at least for SELinux), permission denied on stat() always means that the file exists, but getattr isn't allowed. As for a reproducible test case, probably the simplest example is a vanilla Fedora Core 3 system with SELinux enabled and strict policy. From a regular user account, call os.path.exists("/etc/shadow"). It will return False even though the file exists. For comparison, an `ls -l /etc/shadow` from the command line will simply print 'Permission Denied'. ---------------------------------------------------------------------- Comment By: Terry J. Reedy (tjreedy) Date: 2005-02-16 12:26 Message: Logged In: YES user_id=593130 Does 'access denied' always mean 'present but not readable' in every environment that gives such messages? I ask because I have vague memories of wasting time trying to get access to something that did not exist, because access denied (or something like that) meant that I was denied access even to info about whether it existed or not. In any case, a reproducible example would help someone to verify, fix, and write a test case for this if it is deemed to be a fixable bug. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1117601&group_id=5470 _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com