Re: [Qemu-block] [Qemu-devel] IOTEST 162

[Maxim Levitsky]

On Mon, 2019-09-09 at 13:24 -0400, John Snow wrote:
> 
> On 9/6/19 1:25 PM, Maxim Levitsky wrote:
> > Hi!
> > 
> > I just had a very fun rabbit hole dive, and I want to share it with you.
> > 
> > I notice for some time that iotest 162 fails with that:
> > 
> > -qemu-img: Could not open 'json:{"driver": "nbd", "host": 42}': Failed to 
> > connect socket: Invalid argument
> > +qemu-img: Could not open 'json:{"driver": "nbd", "host": 42}': Failed to 
> > connect socket:
> > Connection timed out
> > 
> > 
> > I didn't bother to report it yet as it started failing more or less when 
> > qemu 4.2 merge window opened,
> > so I thought that maybe something got broken, or maybe something broken in 
> > my environment 
> > (ahem, AF_UNIX path is too long, ahem)
> > 
> > I just didn't had enough time to pay attention to this. Until today.
> > 
> > So I asked Kevin Wolf today, just by the way why I see for some time that
> > iotest 162 fails. for me.
> > 
> > 
> > He told me that it works for him.
> > So I look at the test and I see that it just does
> > 
> > qemu-img info 'json:{"driver": "nbd", "host": 42}'
> > 
> > Supposedly it should fail because 42 is not quoted, and it 
> > doesn't look like a valid host name.
> > 
> > I try with disto's qemu-img (2.11) and I still see that I get the 
> > 'Connection timed out'
> > 
> > Then I ask him to try on his system with '42' quoted and it still passes.
> > 
> > All right - this means that this 42 is parsed. He also mentions that he 
> > uses fedora 29 and I still
> > use fedora 28. So I start a VM with fedora 30, and yep, there it does work 
> > correctly.
> > 
> > All right, that 42 must be parsed as a host name. Yep. 'ping 42' on my 
> > machine tries to ping 0.0.0.42,
> > and in VM exits immediately with 'Invalid argument'
> > All right, lets ping 0.0.0.42. Maybe something in hostname parsing changed, 
> > maybe something parses this on DNS level?
> > Nope, ping 0.0.0.42 works on my machine, fails with invalid argument in 
> > VM...
> > 
> > All right lets strace it
> > 
> > connect(5, {sa_family=AF_INET, sin_port=htons(1025), 
> > sin_addr=inet_addr("0.0.0.42")}, 16) = -1 EINVAL (Invalid argument)
> > 
> > Same thing passes on my machine....
> > 
> > Hmm... this is something in the kernel. Maybe something in iptables/etc. I 
> > don't yet know that
> > area that well to be honest.
> > 
> > So I googled a bit and look what I found:
> > 
> > https://lwn.net/Articles/791086/
> > 
> > And yes, while my machine runs fedora 28, it as usual runs vanilla git 
> > master
> > kernel, which I compile from time to time. Currently I am on 5.3.0-rc4+.
> > 
> > So I must say that nothing less but kernel 5.3.0, breaks iotest 162.
> > 
> > I''l prepare a patch soon to fix this.
> 
> I wonder if I am seeing some related problems, though I am running
> 5.2.11 right now and not 5.3.x:
> 
> 162 is failing in this way:
> 
> -qemu-img: Could not open 'json:{"driver": "ssh", "host": "localhost",
> "port": "0", "path": "/foo"}': Failed to connect socket: Connection refused
> -qemu-img: Could not open 'driver=ssh,host=localhost,port=0,path=/foo':
> Failed to connect socket: Connection refused
> +qemu-img: Could not open 'json:{"driver": "ssh", "host": "localhost",
> "port": "0", "path": "/foo"}': Failed to connect socket: Connection
> timed out
> +qemu-img: Could not open 'driver=ssh,host=localhost,port=0,path=/foo':
> Failed to connect socket: Connection timed out
>  qemu-img: Could not open 'json:{"driver": "ssh", "host": "localhost",
> "port": 0.42, "path": "/foo"}': Parameter 'port' expects a number
>  qemu-img: Could not open
> 'driver=ssh,host=localhost,port=0.42,path=/foo': Parameter 'port'
> expects a number

This must be the same issue, although here it fails like that:


[mlevitsk@maximlenovopc ~/qemu/tests/qemu-iotests]$./check -qcow2 162
QEMU          -- 
"/home/mlevitsk/qemu/tests/qemu-iotests/../../x86_64-softmmu/qemu-system-x86_64"
 -nodefaults -display none -machine accel=qtest
QEMU_IMG      -- "/home/mlevitsk/qemu/tests/qemu-iotests/../../qemu-img" 
QEMU_IO       -- "/home/mlevitsk/qemu/tests/qemu-iotests/../../qemu-io"  
--cache writeback -f qcow2
QEMU_NBD      -- "/home/mlevitsk/qemu/tests/qemu-iotests/../../qemu-nbd" 
IMGFMT        -- qcow2 (compat=1.1)
IMGPROTO      -- file
PLATFORM      -- Linux/x86_64 maximlenovopc 5.3.0-rc4+
TEST_DIR      -- /home/mlevitsk/qemu/tests/qemu-iotests/scratch
SOCKET_SCM_HELPER -- /home/mlevitsk/qemu/tests/qemu-iotests/socket_scm_helper

162      fail       [12:25:07] [12:27:18]                    output mismatch 
(see 162.out.bad)
--- /home/mlevitsk/USERSPACE/qemu/src/tests/qemu-iotests/162.out        
2019-04-07 16:37:54.656311574 +0300
+++ /home/mlevitsk/qemu/tests/qemu-iotests/162.out.bad  2019-09-10 
12:27:18.032903571 +0300
@@ -1,7 +1,7 @@
 QA output created by 162
 
 === NBD ===
-qemu-img: Could not open 'json:{"driver": "nbd", "host": 42}': Failed to 
connect socket: Invalid argument
+qemu-img: Could not open 'json:{"driver": "nbd", "host": 42}': Failed to 
connect socket: Connection timed out
 image: nbd://localhost:PORT
 image: nbd+unix://?socket=42
 
Failures: 162
Failed 1 of 1 tests



Test 147 passes for me with both raw and qcow2 format.

Best regards,
        Maxim Levitsky


> 
> 
> and 147 is failing this way:
> 
> +  File "147", line 243, in test_inet6
> +    if self._try_server_up(address):
> +  File "147", line 156, in _try_server_up
> +    self.assert_qmp(result, 'return', {})
> +  File "/home/bos/jhuston/src/qemu/tests/qemu-iotests/iotests.py", line
> 685, in assert_qmp
> +    result = self.dictpath(d, path)
> +  File "/home/bos/jhuston/src/qemu/tests/qemu-iotests/iotests.py", line
> 661, in dictpath
> +    self.fail('failed path traversal for "%s" in "%s"' % (path, str(d)))
> +AssertionError: failed path traversal for "return" in "{'error':
> {'class': 'GenericError', 'desc': 'Failed to bind socket: Cannot assign
> requested address'}}"
> 
> 
> 
> I'm not sure when the failure started -- this is the first time I'm
> seeing it -- I'm fairly certain I ran these tests Thursday or Friday
> last week.