lckpwdf creates /etc/.pwd.lock + ulckpwdf fails to remove /etc/.pwd.lock

[David Favor]

For the simple program...

#include <stdio.h>
#include <shadow.h>
int main (void) {
   int status = lckpwdf();
   status = ulckpwdf();
   return status;
}

gcc -o simple simple.c

strace ./simple 2>&1 | egrep 'pwd|lckpwdf|ulckpwdf'
open("/etc/.pwd.lock", O_WRONLY|O_CREAT|O_CLOEXEC, 0600) = 3

It appears the macro lckpwdf creates /etc/.pwd.lock + macro ulckpwdf fails to delete this file.

So running a program like vipw creates both /etc/.pwd.lock + /etc/passwd.lock files or
vigr creates both /etc/.pwd.lock + /etc/group.log and in both cases after vipw or vigr
exit /etc/.pwd.lock remains.

[Seth Arnold (seth-arnold)]

-rw------- 1 root root 0 Aug 23 2012 /etc/.pwd.lock

[DiagonalArg (diagonalarg)]

I am running Ubuntu Gnome 16.04, and the /etc/.pwd.lock file has been on my machine since install. I checked a couple of 14.04 machines, and it's the same. That file is making duplicity backups of /etc fail.

[DiagonalArg (diagonalarg)]

I'll add that the same problem is reported at Red Hat: https://bugzilla.redhat.com/show_bug.cgi?id=428337