This with:

$ /lib/x86_64-linux-gnu/libc.so.6 
GNU C Library (Debian GLIBC 2.34-3) stable release version 2.34.
Copyright (C) 2021 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
Compiled by GNU CC version 11.3.0.
libc ABIs: UNIQUE IFUNC ABSOLUTE

> Hmm, I'm not sure we should allow clone3 unconditionally since it can do lots of
> things, and I'd expect that its capabilities will only grow over time. OTOH, BPF
> (or at least the libseccomp library) don't support pointer indirections which
> would be needed to inspect the structure fields. See
> https://lwn.net/Articles/822256/.
> Any opinions?

No opinion from me, but FWIW Docker seems to allow clone3 in its default
policy:
https://github.com/docker/docker-ce/commit/522fcd0056
https://github.com/containerd/containerd/pull/5982

Thanks,

-- 
Basil

In GNU Emacs 29.0.50 (build 1, x86_64-pc-linux-gnu, X toolkit, cairo version 1.16.0, Xaw3d scroll bars)
 of 2022-08-20 built on tia
Repository revision: 3312710fd672021b17983ef2287dbd57a9a110a1
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12101004
System Description: Debian GNU/Linux bookworm/sid

Configured using:
 'configure 'CFLAGS=-Og -ggdb3' --config-cache --prefix=/home/blc/.local
 --enable-checking=structs --with-file-notification=yes
 --with-x-toolkit=lucid --with-x'

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TOOLKIT_SCROLL_BARS WEBP X11 XAW3D XDBE XIM XINPUT2 XPM LUCID ZLIB

Important settings:
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  value of $XMODIFIERS: @im=ibus
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Major mode: Lisp Interaction

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Load-path shadows:
None found.

Features:
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mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
cl-loaddefs cl-lib sendmail rfc2047 rfc2045 ietf-drums mm-util
mail-prsvr mail-utils rmc iso-transl tooltip eldoc paren electric
uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel
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term/tty-colors frame minibuffer nadvice seq simple cl-generic
indonesian philippine cham georgian utf-8-lang misc-lang vietnamese
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romanian slovak czech european ethiopic indian cyrillic chinese
composite emoji-zwj charscript charprop case-table epa-hook
jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button loaddefs
faces cus-face macroexp files window text-properties overlay sha1 md5
base64 format env code-pages mule custom widget keymap
hashtable-print-readable backquote threads dbusbind inotify lcms2
dynamic-setting system-font-setting font-render-setting cairo x-toolkit
xinput2 x multi-tty make-network-process emacs)

Memory information:
((conses 16 36336 7449)
 (symbols 48 5084 0)
 (strings 32 13829 1888)
 (string-bytes 1 381827)
 (vectors 16 9205)
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