Comment 8 for bug 1818264

Before upgrade:

root@c:~# qemu-img create -f qcow2 test 1024 2>&1
Formatting 'test', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
root@c:~# qemu-io -f qcow2 -C -c 'read 0 1024' test
qemu-io: /build/qemu-w2bpg6/qemu-2.12+dfsg/block/io.c:1098: bdrv_co_do_copy_on_readv: Assertion `skip_bytes < pnum' failed.
Aborted (core dumped)

Installing the upgrade
apt install qemu-utils
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  qemu-block-extra qemu-system-common
Suggested packages:
  debootstrap
The following packages will be upgraded:
  qemu-block-extra qemu-system-common qemu-utils
3 upgraded, 0 newly installed, 0 to remove and 51 not upgraded.
Need to get 1057 kB of archives.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] Y
Get:1 http://archive.ubuntu.com/ubuntu cosmic-proposed/main amd64 qemu-utils amd64 1:2.12+dfsg-3ubuntu8.4 [987 kB]
Get:2 http://archive.ubuntu.com/ubuntu cosmic-proposed/main amd64 qemu-system-common amd64 1:2.12+dfsg-3ubuntu8.4 [31.0 kB]
Get:3 http://archive.ubuntu.com/ubuntu cosmic-proposed/main amd64 qemu-block-extra amd64 1:2.12+dfsg-3ubuntu8.4 [39.9 kB]
Fetched 1057 kB in 0s (3445 kB/s)
(Reading database ... 55838 files and directories currently installed.)
Preparing to unpack .../qemu-utils_1%3a2.12+dfsg-3ubuntu8.4_amd64.deb ...
Unpacking qemu-utils (1:2.12+dfsg-3ubuntu8.4) over (1:2.12+dfsg-3ubuntu8.3) ...
Preparing to unpack .../qemu-system-common_1%3a2.12+dfsg-3ubuntu8.4_amd64.deb ...
Unpacking qemu-system-common (1:2.12+dfsg-3ubuntu8.4) over (1:2.12+dfsg-3ubuntu8.3) ...
Preparing to unpack .../qemu-block-extra_1%3a2.12+dfsg-3ubuntu8.4_amd64.deb ...
Unpacking qemu-block-extra:amd64 (1:2.12+dfsg-3ubuntu8.4) over (1:2.12+dfsg-3ubuntu8.3) ...
Setting up qemu-block-extra:amd64 (1:2.12+dfsg-3ubuntu8.4) ...
Setting up qemu-utils (1:2.12+dfsg-3ubuntu8.4) ...
Processing triggers for man-db (2.8.4-2) ...
Setting up qemu-system-common (1:2.12+dfsg-3ubuntu8.4) ...

Then test succeeds:
qemu-io -f qcow2 -C -c 'read 0 1024' test
read 1024/1024 bytes at offset 0
1 KiB, 1 ops; 0.0001 sec (7.570 MiB/sec and 7751.9380 ops/sec)

Along the bigger SRU for Bionic I have already run this code through some more regression checks which all were fine.
Due to the above, setting verified for the cosmic release