Re: uid

From: Tracy Stenvik (imf@u.washington.edu)
Date: Mon Sep 18 2000 - 15:41:13 EST


Yes, 2.4 has 32bit uid/gid support. No, 2.2 doesn't, but there is a patch
from http://www.engin.umich.edu/caen/systems/Linux. You'll probably have
to do some work to fit the patches into the latest 2.2 kernels though, as
they're no longer being maintained in leu of 2.4.

In addition to running a 2.4 kernel, you'll also need to hack up glibc to
recognize the new syscalls the kernel provides for 32bit uid/gid support.
It's claimed that glibc 2.2 will have this, but you'll have to wait until
it is released. I hacked 2.1.3 with satisfactory results.

If you use quotacheck from quota-x.x.tar.gz and you enable the direct ext2
support stuff, you'll have to hack it up to properly reassemble uids/gids.
The same applies to debugfs from e2progs-x.y.tar.gz, and any other utility
which accesses the ext2 filesystem directly - as opposed to using standard
filesystem routines.

If you're interested in process accounting, be aware that the accounting
file format is still mired with 16bit uids/gids. Fortunately this one is
trivial to fix, as long as you don't mind abandoning your old accounting
files. I think the 2.2->2.4 transition would be a great time to make the
switch, officially.

Be aware that other utilities that deal with uids/gids may break. Tar is
one of them. The tar format specifies 16bit uids/gids. Patching tar may
not be wise if you're going to share the tarballs with other systems. ELF
core files also suffers this problem. I'm sure I left out others.

---
Tracy Stenvik
University Computing Services 354843.  University of Washington
email: imf@u.washington.edu  voice: (206) 685-3344

On Mon, 18 Sep 2000, octave klaba wrote:

> Hi, > I read that the hard limit of the number of the users on > 2.2.x is 65000 and on 2.4.x it will be more. > I just wonder if it is true and if we have to wait for 2.4.x > to have more that 65000 users with kernel's quota management ? > > Thanks > Octave > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > Please read the FAQ at http://www.tux.org/lkml/ >

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/



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