[PLUG] rebuilding kernel with NGROUPS_MAX changed

Michael Rasmussen mikeraz at patch.com
Fri Jan 16 11:04:02 UTC 2004


	Background
There is a problem if one if using SAMBA/Winbind and a user attempting to login to a system with their authentication from a NT Domain.  If the user belongs to more than NGROUPS_MAX (defined in limits.h) their authentication will fail.

See http://lists.samba.org/archive/samba-technical/2003-March/027605.html for a reference. 

In Linux this number is 32.  We have many users that belong is 50 or more groups. (Don't ask, I didn't design the model.)

In a followup message to the one linked above it is stated that some utilities in userland are compiled with NGROUPS_MAX.  So if one wants to fix the problem, a change to the kernel source and a recompile can lead to problems down the road.  However, this was in the context of Solaris.

	Question
Is this a problem in Linux land?  Or can we indeed change NGROUPS_MAX, recompile the kernel and be good to go?  What "shoot self in foot" potentials are we looking at?



-- 
      Michael Rasmussen  aka  mikeraz
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