[Qemu-devel] [PATCH v2 0/2] seccomp action, prefer KILL_PROCESS or TRAP

[Marc-André Lureau]

Hi,

The seccomp action SCMP_ACT_KILL results in immediate termination of
the thread that made the bad system call. However, qemu being
multi-threaded, it keeps running. There is no easy way for parent
process / management layer (libvirt) to know about that situation.

Instead, the default SIGSYS handler when invoked with SCMP_ACT_TRAP
will terminate the program and core dump.

This may not be the most secure solution, but probably better than
just killing the offending thread. SCMP_ACT_KILL_PROCESS has been
added in Linux 4.14 to improve the situation, which I propose to use
by default if available.

Related to:
https://bugzilla.redhat.com/show_bug.cgi?id=1594456

v2:
- fix clang unused inline warning
- add acked-by/r-b tags

Marc-André Lureau (2):
  seccomp: use SIGSYS signal instead of killing the thread
  seccomp: prefer SCMP_ACT_KILL_PROCESS if available

 qemu-seccomp.c | 30 +++++++++++++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

-- 
2.18.0.547.g1d89318c48