seccomp: don't block getters for resource control syscalls
authorDaniel P. Berrangé <berrange@redhat.com>
Wed, 30 Jun 2021 14:19:38 +0000 (15:19 +0100)
committerDaniel P. Berrangé <berrange@redhat.com>
Wed, 14 Jul 2021 13:15:52 +0000 (14:15 +0100)
commit2ce949a4c187b2a6aa68ab03216ee271b408fa63
treec1f389963144c3f79ebce879b1366ac8337d6305
parentcfb47f2178c2c9c81870aab0bc0c93e5758cff86
seccomp: don't block getters for resource control syscalls

Recent GLibC calls sched_getaffinity in code paths related to malloc and
when QEMU blocks access, it sends it off into a bad codepath resulting
in stack exhaustion[1]. The GLibC bug is being fixed[2], but none the
less, GLibC has valid reasons to want to use sched_getaffinity.

It is not unreasonable for code to want to run many resource syscalls
for information gathering, so it is a bit too harsh for QEMU to block
them.

[1] https://bugzilla.redhat.com/show_bug.cgi?id=1975693
[2] https://sourceware.org/pipermail/libc-alpha/2021-June/128271.html
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Acked-by: Eduardo Otubo <otubo@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
softmmu/qemu-seccomp.c