Failed to reproduce bugs on the rebuilt Jammy source (not Jammy binary
though).

1.  String fields like `ruser` are not pointer to a string but a character 
array (representing a string) in `struct proc_t`.
2.  User/group names are filled from UID/GID even if reading 
`/proc/[PID]/status` fails, normally resulting in the string "root" 
(uninitialized UID/GID [0] are both recognized as root).
3.  Even those names are not touched, they are effectively initialized as an 
empty string.

** Description changed:

  I encountered with crashes on top.
  
  Reproduced Version: 2:4.0.4-4ubuntu3.2 (noble; Ubuntu 24.04 LTS)
- Affected Versions: All currently supported versions (I guess)
+ Affected Versions (guessed by the reporter): Noble (Ubuntu 24.04 LTS) or later
  
  It requires:
  *   A libproc2-0 depending program like `top` (as I encountered) and `ps` (as 
reported upstream).
  *   Printing certain columns like RUSER is enabled.
  *   On ps, probably non-UTF-8 locale is required (because UTF-8 string 
processing path workarounds crashes).
  
  Still, (as I explain later) this is a race condition issue and for
  reproduction without patching the program, some randomness is involved
  (the upstream GitLab issue page provides patching method for reliable
  crash reproduction).
  
  1.  The system should be under high process creation/deletion pressure (where 
many processed are created and destroyed in a short period of time).
  2.  On top, reproducibility raises if higher number of processes are printed 
(i.e. the terminal is large and/or zoomed out) and the delay value (default: 3 
seconds) is lower.
  3.  On ps, set LC_ALL=C to avoid UTF-8-based locales.
  
  On upstream, it is found to be a race condition issue on libproc2-0
  (cause is discovered by me) and fixed by Jim Warner (the main commit is
  https://gitlab.com/procps-
  ng/procps/-/commit/a5708118a4f3184cb5a3e2faa219807e73f007d3).
  
  As suggested by Mike Gulick, there may be a possibility synchronizing
  with Debian (for backporting the fix).
  
  cf. https://gitlab.com/procps-ng/procps/-/issues/380

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https://bugs.launchpad.net/bugs/2120904

Title:
  top/ps crashes on high process creation/deletion pressure

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