*** Bug 1461677 has been marked as a duplicate of this bug. ***

Fix included in qemu-kvm-1.5.3-145.el7

Set the bug as verified according to the test result.

Verified the issue with below packages:
kernel-3.10.0-728.el7.x86_64
qemu-kvm-1.5.3-145.el7

Test steps:
1. Setup ssh environment
#ssh-keygen
#ssh-copy-id root.73.83
#exec /usr/bin/ssh-agent $SHELL
#ssh-add

2. Create snapshot via ssh protocol
# qemu-img create -f qcow2 -b 'json:{"file.driver":"ssh", "file.host":"10.73.73.83", "file.port":"22", "file.path":"/home/tests/diskfile/rhel75.qcow2", "file.user":"root", "file.host_key_check":"no"}' ssh.qcow2
Formatting 'ssh.qcow2', fmt=qcow2 size=21474836480 backing_file='json:{"file.driver":"ssh", "file.host":"10.73.73.83", "file.port":"22", "file.path":"/home/tests/diskfile/rhel75.qcow2", "file.user":"root", "file.host_key_check":"no"}' encryption=off cluster_size=65536 lazy_refcounts=off

3. Check info of image
# qemu-img info ssh.qcow2 
image: ssh.qcow2
file format: qcow2
virtual size: 20G (21474836480 bytes)
disk size: 17M
cluster_size: 65536
backing file: json:{"file.driver":"ssh", "file.host":"10.73.73.83", "file.port":"22", "file.path":"/home/tests/diskfile/rhel75.qcow2", "file.user":"root", "file.host_key_check":"no"}
Format specific information:
    compat: 1.1
    lazy refcounts: false

4. Boot up the guest

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHSA-2018:0816