From 08dc2a4dc481916fae9597220ad0faf3f6ed70c1 Mon Sep 17 00:00:00 2001
From: Eduardo Otubo <otubo@redhat.com>
Date: Mon, 16 Nov 2020 15:15:38 -0500
Subject: [PATCH 1/5] seccomp: fix killing of whole process instead of thread
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RH-Author: Eduardo Otubo <otubo@redhat.com>
Message-id: <20201116151538.22254-1-otubo@redhat.com>
Patchwork-id: 99654
O-Subject: [RHEL-8.3.0/RHEL-8.4.0 qemu-kvm PATCH] seccomp: fix killing of whole process instead of thread
Bugzilla: 1880546
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: Danilo de Paula <ddepaula@redhat.com>
RH-Acked-by: Marc-André Lureau <marcandre.lureau@redhat.com>

BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1890885
BRANCH: rhel-8.3.0
UPSTREAM: Merged
BREW: https://brewweb.engineering.redhat.com/brew/taskinfo?taskID=1890885

BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1880546
BRANCH: rhel-8.4.0
UPSTREAM: Merged
BREW: https://brewweb.engineering.redhat.com/brew/taskinfo?taskID=33125023

From: Daniel P. Berrangé <berrange@redhat.com>

Back in 2018 we introduced support for killing the whole QEMU process
instead of just one thread, when a seccomp rule is violated:

  commit bda08a5764d470f101fa38635d30b41179a313e1
  Author: Marc-André Lureau <marcandre.lureau@redhat.com>
  Date:   Wed Aug 22 19:02:48 2018 +0200

    seccomp: prefer SCMP_ACT_KILL_PROCESS if available

Fast forward a year and we introduced a patch to avoid killing the
process for resource control syscalls tickled by Mesa.

  commit 9a1565a03b79d80b236bc7cc2dbce52a2ef3a1b8
  Author: Daniel P. Berrangé <berrange@redhat.com>
  Date:   Wed Mar 13 09:49:03 2019 +0000

    seccomp: don't kill process for resource control syscalls

Unfortunately a logic bug effectively reverted the first commit
mentioned so that we go back to only killing the thread, not the whole
process.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Eduardo Otubo <otubo@redhat.com>
(cherry picked from commit e474e3aacf4276eb0781d11c45e2fab996f9dc56)
Signed-off-by: Eduardo Otubo <otubo@redhat.com>
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
 qemu-seccomp.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/qemu-seccomp.c b/qemu-seccomp.c
index e0a1829b3dd..8325ecb766e 100644
--- a/qemu-seccomp.c
+++ b/qemu-seccomp.c
@@ -136,8 +136,9 @@ static uint32_t qemu_seccomp_get_action(int set)
 
             if (qemu_seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &action) == 0) {
                 kill_process = 1;
+            } else {
+                kill_process = 0;
             }
-            kill_process = 0;
         }
         if (kill_process == 1) {
             return SCMP_ACT_KILL_PROCESS;
-- 
2.27.0