From 2f84739e8f2928b98190f76035e00db82ef6dc7e Mon Sep 17 00:00:00 2001
From: Thomas Huth <thuth@redhat.com>
Date: Tue, 14 Sep 2021 13:29:59 +0200
Subject: [PATCH] tools/virtiofsd: Add fstatfs64 syscall to the seccomp
 allowlist
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RH-Author: Thomas Huth <thuth@redhat.com>
RH-MergeRequest: 37: tools/virtiofsd: Add fstatfs64 syscall to the seccomp allowlist
RH-Commit: [1/1] 464231b7cfa7159d9adfc4fc01b26bc3b3a66ecd
RH-Bugzilla: 2001728
RH-Acked-by: Daniel P. Berrangé <berrange@redhat.com>
RH-Acked-by: Cornelia Huck <cohuck@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: Philippe Mathieu-Daudé <philmd@redhat.com>

The virtiofsd currently crashes on s390x when doing something like
this in the guest:

 mkdir -p /mnt/myfs
 mount -t virtiofs myfs /mnt/myfs
 touch /mnt/myfs/foo.txt
 stat -f /mnt/myfs/foo.txt

The problem is that the fstatfs64 syscall is called in this case
from the virtiofsd. We have to put it on the seccomp allowlist to
avoid that the daemon gets killed in this case.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2001728
Suggested-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 tools/virtiofsd/passthrough_seccomp.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/virtiofsd/passthrough_seccomp.c b/tools/virtiofsd/passthrough_seccomp.c
index 62441cfcdb..2edbd3af95 100644
--- a/tools/virtiofsd/passthrough_seccomp.c
+++ b/tools/virtiofsd/passthrough_seccomp.c
@@ -51,6 +51,7 @@ static const int syscall_allowlist[] = {
     SCMP_SYS(fsetxattr),
     SCMP_SYS(fstat),
     SCMP_SYS(fstatfs),
+    SCMP_SYS(fstatfs64),
     SCMP_SYS(fsync),
     SCMP_SYS(ftruncate),
     SCMP_SYS(futex),
-- 
2.27.0