misc/56324: lib/libc/stdio/t_fopen tests overflow default tmpfs

[gson%gson.org@localhost (Andreas Gustafsson)]

>Number:         56324
>Category:       misc
>Synopsis:       lib/libc/stdio/t_fopen tests overflow default tmpfs
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    misc-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jul 22 14:50:00 +0000 2021
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current
>Organization:

>Environment:
System: NetBSD
Architecture: i386
Machine: i386
>Description:

One of my testbeds runs the tests on a physical i386 laptop with 512
MB RAM.  It gets configured with a 128 MB tmpfs /tmp by sysinst when
using default settings.  On this machine, the stdio_intr_iofbf and
stdio_intr_ionbf test cases of the lib/libc/stdio/t_fopen test fail
with error messages such as:

  echo: write error: No space left on device
  t_intr: ERROR: Cannot create results file '/tmp/atf-run.nHCOtT/tcr'

Logs:

  https://www.gson.org/netbsd/bugs/build/i386-laptop/2021/2021.07.22.04.46.29/test.html#lib_libc_stdio_t_intr_stdio_intr_iofbf

>How-To-Repeat:

Perform a default install on a system with 512 MB RAM, then run the
ATF tests.

>Fix:

Either reduce the disk space requirements of these test cases, or skip
them on systems that don't have enough space.