Re: [musl] Re: async-signal-safety of chroot

[Florian Weimer <fweimer@redhat.com>]

* Rich Felker:

> On Wed, Sep 23, 2026 at 04:17:03AM +0000, John Scott wrote:
>> On Tue, 2026-09-22 at 21:34 -0400, Rich Felker wrote:
>> > Since it's no longer standard, there is no standard governing chroot,
>> 
>> On this claim only, I believe you're technically mistaken: ISO/IEC
>> 23360-1-2:2021 (Linux Standard Base: Core specification generic
>> part) is a current International Standard. It incorporates the
>> definition of chroot() from SUSv2 by reference without amendment, so
>> the same async-signal-safety limitations apply.
>
> Linux Standard Base is not relevant. It is not a standard musl aims to
> conform to, and it is largely an ad hoc third party description of a
> very old version of the glibc ABI and its integration into Red Hat
> Linux.

And glibc does not aim to conform to Linux Standard Base, either.  Only
very few architectures meet the symbol version requirements in ISO/IEC
23360-1-2:2021.  Any architecture that was added after glibc 2.3 is not
compliant (not even with the generic part).  This is a defect in the
standard.

Thanks,
Florian