Re: UPG and the default umask

[Bastien ROUCARIES <roucaries.bastien@gmail.com>]

On Mon, May 17, 2010 at 3:34 PM, Marvin Renich <mrvn@renich.org> wrote:
> * Reinhard Tartler <siretart@debian.org> [100517 08:56]:
>> Let's have a look at the source. Note that options->usergroups is set
>> iff the option "usergroups" is used.
>>
>> ,----[modules/pam_umask/pam_umask.c]
>> | /* Set the process nice, ulimit, and umask from the
>> |    password file entry.  */
>> | static void
>> | setup_limits_from_gecos (pam_handle_t *pamh, options_t *options,
>> |                      struct passwd *pw)
>> | {
>> |   char *cp;
>> |
>> |   if (options->usergroups)
>> |     {
>> |       /* if not root, and UID == GID, and username is the same as
>> |      primary group name, set umask group bits to be the same as
>> |      owner bits (examples: 022 -> 002, 077 -> 007).  */
>> |       if (pw->pw_uid != 0 && pw->pw_uid == pw->pw_gid)
>> |     {
>> |       struct group *grp = pam_modutil_getgrgid (pamh, pw->pw_gid);
>> |       if (grp && (strcmp (pw->pw_name, grp->gr_name) == 0))
>> |         {
>> |           mode_t oldmask = umask (0777);
>> |           umask ((oldmask & ~070) | ((oldmask >> 3) & 070));
>> |         }
>> |         }
>> |     }
>> `----

Another bug is the code does not check if they are only one user on the group.

Regards

Bastien