Re: adduser race conditions

2021-02-22 Thread Christian Ehrhardt
On Fri, Feb 19, 2021 at 6:19 PM Brent W. Baccala wrote: > > Hi - > > I've found at least one race condition in the adduser script on Ubuntu 18. > > The program searches for an available UID (and GID), then adds the new user > with the selected UID/GID numbers without any synchronization, so two

adduser race conditions

2021-02-19 Thread Brent W. Baccala
Hi - I've found at least one race condition in the adduser script on Ubuntu 18. The program searches for an available UID (and GID), then adds the new user with the selected UID/GID numbers without any synchronization, so two near-simultaneous invocations of the program can produce two users