From: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Date: Fri, 3 Nov 2017 08:46:58 +0000 (+0100)
Subject: apparmor: allow qemu to read max_segments
X-Git-Tag: v3.10.0-rc1~203
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=37a4e6d430856727a1093c88f79c3882da5a646c;p=thirdparty%2Flibvirt.git

apparmor: allow qemu to read max_segments

Since qemu 2.9 via 9103f1ce "file-posix: Consider max_segments for
BlockLimits.max_transfer" this is a new access that is denied by the
qemu profile.

It is non fatal, but prevents the fix mentioned to actually work.
It should be safe to allow reading from that path.

Since qemu opens a symlink path we need to translate that for apparmor from
"/sys/dev/block/*/queue/max_segments" to
"/sys/devices/**/block/*/queue/max_segments"

Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
---

diff --git a/examples/apparmor/libvirt-qemu b/examples/apparmor/libvirt-qemu
index 97dd2d45a9..064501f08e 100644
--- a/examples/apparmor/libvirt-qemu
+++ b/examples/apparmor/libvirt-qemu
@@ -169,6 +169,9 @@
   # for rbd
   /etc/ceph/ceph.conf r,
 
+  # for file-posix getting limits since 9103f1ce
+  /sys/devices/**/block/*/queue/max_segments r,
+
   # for ppc device-tree access
   @{PROC}/device-tree/ r,
   @{PROC}/device-tree/** r,