Hello,
Sorry for the delayed response... Trying to burn up some PTO.
On 11/23/20 1:17 PM, Jacob Shivers wrote:
> Commit 2f682f25c642fcfe7c511d04bc9d67e732282348 changed existing
> behavior to avoid a deadlock for users using Kerberized NFS home dirs.
>
> However, this also prevents users leveraging their own k5identity
> files under their home directory and instead rpc.gssd uses a
> system-wide /.k5identity file. For users expecting to use their own
> k5identity file this is certainly unexpected.
So how is the deadlock not happening when ~/.k5identity is on a NFS
home directory? What am I missing?
>
> Below is some pseudo code that was proposed and would just add a flag
> allowing for the behavior prior to
> 2f682f25c642fcfe7c511d04bc9d67e732282348:
>
> /* psudo code snippet starts here */
> /*
> * Some krb5 routines try to scrape info out of files in the user's
> * home directory. This can easily deadlock when that homedir is on a
> - * kerberized NFS mount. By setting $HOME unconditionally to "/", we
> + * kerberized NFS mount. Some users may not have $HOME on NFS.
> + * By default setting $HOME unconditionally to "/", we
> * prevent this behavior in routines that use $HOME in preference to
> * the results of getpw*.
> + * Users who have $HOME on krb5-NFS should set
> `--home-not-kerberized` in argv
> + * Users who have $HOME on krb5-NFS but want to use their
> $HOME anyway should set NFS_HOME_ACCESSIBLE=TRUE
> */
> + if (argv == '--home-not-kerberized') ||
> (getenv("NFS_HOME_ACCESSIBLE") == 'TRUE') {
> + log.debug('Not masking $HOME, this breaks on Kerberized $HOME');
> + }
> + else {
> + log.debug('Assuming $HOME requires Kerberos, use
> `--home-not-kerberized` to change this behavior');
> if (setenv("HOME", "/", 1)) {
> printerr(1, "Unable to set $HOME: %s\n", strerror(errn));
> exit(1);
> }
> + }
> /* psudo code snippet ends here */
In general I'm pretty reluctant to add flags but what is needed
to do so is a company single letter flag '-H' and a man page
entry describing the flag.
>
> While acknowledging the use of this flag for Kerberized NFS home dirs
> is undesirable and would cause a deadlock, there should be no issue
> for users not using Kerberized NFS home dirs.
What apps are you using that is seeing this problem?
steved.
