Skipping unknown fields is by design, to provide compatibility with other 
versions of the same IDL. If you change that behaviour and it works for you, 
thats perfectly fine. I would however not expect the official version to work 
that way.

I'm not sure but if it is corrupted data, could adding some kind of CRC do the 
trick? Just an idea.

Have fun,
JensG
________________________________
Von: Mingmin Liu
Gesendet: 20.01.2015 06:45
An: [email protected]
Betreff: Re: When will TProtocolUtil.skip() be called

Thanks for all your response

After dump the client request, finally find the reason: we receive some bad
request and our server try to de-serialize it, these de-serialization will
finally fail, but it can take as long as 10 minute, during which costs a
lot of CPU time:

our-server/broken/deserialize_gt5_ms: (average=94619, count=214,
*maximum=776506*, minimum=6, p50=85881, p90=115957, p95=128163, p99=258239,
p999=776506, p9999=776506, sum=20248467)

In our case, we choose a simple solution: change the thrift generated code,
and throw Exception directly when we see known field during
de-serialization, instead of skip() it.

PS. will update thrift to the latest version and check if this still exists.

On Tue Jan 13 2015 at 3:16:21 PM Jens Geyer <[email protected]> wrote:

> > deserialize broken binary data
>
> In case of binary it *might* be the case, but OTOH it is unlikely that
> there is no other error occurring and the structure of the broken data
> follows the binary protocol so close to prevent any other errors.
>
> So far I fully agree with what has been said. Unless we have more
> information, the most likely case seems that some terribly outdated client
> tries to reach the server.  However, it is still guesswork and the real
> cause still may be something else.
>
> Are you doing some logging at your servers? What do these logs say?
>
> Have fun,
> JensG
>
> From: [email protected]
> Date: Tue, 13 Jan 2015 03:02:46 +0000
> Subject: Re: When will TProtocolUtil.skip() be called
> To: [email protected]
>
> Hi Randy,
>
> Thanks for your reply.
> In my case, the server is guaranteed to be using the latest IDL, and we
> have not deleted any field when evolving our IDL.
> So may I say that the TProtocolUtil.skip is called because it is trying to
> deserialize some broken or malicious binaries?
> I also notice that the server spend a lot of time(7% of cpu time) calling
> TProtocolUtil.skip,  is that an expected behaviour?
>
>
> Also, is it safe for us to update the server to 0.9.2, while leave the
> clients using 0.7.0?
> Thanks
> On Tue Jan 13 2015 at 2:09:34 AM Randy Abernethy <[email protected]> wrote:
> Hello Mingmin Liu,
>
>
>
> There is at least one other case for skip.
>
>
>
> 3. new server sees data from old client and old client is still
>
> transmitting a field which has been deleted in new server IDL.
>
>
>
> Also I would note that Apache Thrift 0.7.0 is several years old, the
>
> current release is 0.9.2 and many improvements and subtle changes have
>
> taken place since 0.7.0.
>
>
>
> Best,
>
> Randy
>
>
>
> On Mon, Jan 12, 2015 at 12:55 AM, Mingmin Liu
>
> <[email protected]> wrote:
>
> > I am using thrift 0.7.0 on my server, and recently find sometimes my
> server
>
> > busy calling TProtocolUtil.skip().
>
> >
>
> > stack trace:
>
> >
>
> > "New I/O  worker #75" daemon prio=10 tid=0x00007f7804892000
>
> > nid=0x51601 runnable [0x00007f76129e7000]
>
> >    java.lang.Thread.State: RUNNABLE
>
> >     at org.apache.thrift.protocol.TProtocolUtil.skip(TProtocolUtil.
> java:122)
>
> >     at org.apache.thrift.protocol.TProtocolUtil.skip(TProtocolUtil.
> java:60)
>
> >     at com.My_Thrift_Object.read(My_Thrift_Object.java:958)
>
> >     at org.apache.thrift.TDeserializer.deserialize(TDeserializer.
> java:69)
>
> >
>
> > this happens when I try to deserialize the binary content from client.
>
> >
>
> > Is it true that TProtocolUtil .skip() will be called only  when
>
> > My_Thrift_Object see some field that it doesn't know ?
>
> >
>
> > if yes, when will this happen?
>
> >
>
> > I can come up with 2 conditions:
>
> >
>
> > 1. old server see data from new client and the new client has defined
> some
>
> > new field in thrift.
>
> > 2. the binary content is corrupted or someone maliciously build up it.
>
> >
>
> > is my understanding right?
>
>

Reply via email to