stress-ng opcode test should run with call capabilities disabled

[Colin Ian King]

I use stress-ng to stress CPU(Xeon E3, CentOS7). During the test, I found that system clock has been modified to 1970 or 1969 strangely, but this modification has no effect to rtc. For a tough debug, found stress-opcode cause this modification, below is the code

((void (*)(void))(ops_begin + mwc8()))();

And I limit test to opcode only, like this :

./stress-ng --opcode 0 --timeout 3m --log-file log/opcode.log

The test also cause different results, like user logout, gibberish output and so on. Can anyone explain this test, I have read some short description about opcode in cpu.job, but still question how the test code work. For the system time is changed, but the test past, how can I how if the system work correctly or not?

[Colin Ian King (colin-king)]

Fix committed: 740b5b85c6ab10253765f02c7adc256c5fc18dc2 ("stress-opcode: drop all capabilities so we can't do much damage")

[Launchpad Janitor (janitor)]

This bug was fixed in the package stress-ng - 0.08.13-1

---------------
stress-ng (0.08.13-1) unstable; urgency=medium

  * stress-rdrand: use 32 bit rdrand for i386
  * stress_drop_capabilities: voidify name to avoid warning
  * Enable 64 bit large file system support by default
  * debian/rules: Add hardening=+all
  * manual: fix several spelling mistakes
  * stress-cpu: fix spelling mistake "assigment" -> "assignment"
  * stress-ng: fix spelling mistake "afer" -> "after"
  * stress-opcode: drop all capabilties so we can't do much
    damage (LP: #1714044)
  * helper: add stress_drop_capabilities to drop all capabilities
  * stress-socket-diag: use new HAVE_SOCK_DIAG_H build time check flag
  * Add sock_diag.h auto configure build time checking
  * Add sockdiag stressor
  * stress-fcntl: fix build failure on SLES11 SP4 (LP: #1709905)
  * stress-cyclic: fix build warning on systems w/o atomic ops
  * stress-softlockup: fix build warning on systems w/o atomic ops

 -- Colin King <email address hidden> Wed, 30 Aug 2017 22:06:11 +0100