[Virtio-fs] [PATCH] virtiofsd: Add `sigreturn` to the seccomp whitelist

[Marc Hartmayer]

"Dr. David Alan Gilbert" <dgilbert at redhat.com> writes:

> * Marc Hartmayer (mhartmay at linux.ibm.com) wrote:
>> The virtiofsd currently crashes on s390x. This is because of a
>> `sigreturn` system call. See audit log below:
>> 
>> type=SECCOMP msg=audit(1669382477.611:459): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=system_u:system_r:virtd_t:s0-s0:c0.c1023 pid=6649 comm="virtiofsd" exe="/usr/libexec/virtiofsd" sig=31 arch=80000016 syscall=119 compat=0 ip=0x3fff15f748a code=0x80000000AUID="unset" UID="root" GID="root" ARCH=s390x SYSCALL=sigreturn
>
> I'm curious; doesn't that mean that some signal is being delivered and
> you're returning?  Which one?

code=0x80000000 means that the seccomp action SECCOMP_RET_KILL_PROCESS
is taken => process is killed by a SIGSYS signal (31) [1].

At least, that’s my understanding of this log message.

[1] https://man7.org/linux/man-pages/man2/seccomp.2.html

[…snip…]

> -- 
> Dr. David Alan Gilbert / dgilbert at redhat.com / Manchester, UK
>
-- 
Kind regards / Beste Grüße
   Marc Hartmayer

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