From Bugzilla Helper: User-Agent: Mozilla/4.0 (compatible; MSIE 5.5; Windows 98) Description of problem: passwd reports "authentication tokens updated successfully" even though shadow file is locked and no changes are made How reproducible: Always Steps to Reproduce: 1. touch /etc/shadow.lock 2. passwd anyuser Actual Results: passwd program reports "all authentication tokens updated successfully" Expected Results: passwd program should report an error if it can't get a lock on /etc/shadow Additional info: I'm using Redhat 6.0, however I have tried upgrading PAM, pwdb, passwd, and shadow-utils to 6.2 levels. No effect on this problem.
Additionally, touching "/etc/passwd.lock" instead of "/etc/shadow.lock" will cause passwd to report failure - even though it succeeded! Exactly the reverse of the first problem...
This doesn't apply to the current Fedora/RHEL distributions the passwd locking is done using lckpwdf function which uses /etc/.pwd.lock file and it should handle the locking correctly.