[reSIProcate] NULL Pointer crash with resip 1.3.3

Wed Jul 23 11:06:11 CDT 2008

I'm not sure I fully understand yet why the crash is happening.  The logs
seem to indicated that the ClientSubscription is handling two 408
responses????  For some reason the two 408's have the same TID, but a
different to tag - very strange.

SIP: [.\ClientSubscription.cxx:59] ClientSubscription::dispatch SipResp: 408
tid=151dd73cc5746622 cseq=SUBSCRIBE / 2 from(wire)

SIP: [.\ClientSubscription.cxx:114] processing client subscription response

SIP: [.\ClientSubscription.cxx:168] Received 408 to SUBSCRIBE
<sip:kristie.lomond at sip.sightspeed.com>;tag=10.11374.1216071735.678374

.

SIP: [.\ClientSubscription.cxx:59] ClientSubscription::dispatch SipResp: 408
tid=151dd73cc5746622 cseq=SUBSCRIBE / 2 from(wire)

SIP: [.\ClientSubscription.cxx:114] processing client subscription response

SIP: [.\ClientSubscription.cxx:168] Received 408 to SUBSCRIBE
<sip:kristie.lomond at sip.sightspeed.com>;tag=10.11385.1216071758.680732

But I did find another issue with ClientSubscriptions, and the fix for this
may end up stopping the crash as well.

The problem is that when ClientSubscription::end is called, an un-subscribe
message is sent out.  Normally if this is successful, then we wait for a
Notify to arrive with subscription-state terminated, before destroying the
ClientSubscription.  However if this un-subscribe request fails, then the
whole AppDialogSet reuse and ClientSubscription retry logic kicks in.
However the retry request generated is not an unsubscribe request, it is a
new subscription that is retried.  I've attached a patch that will just
terminate the ClientSubscription, if we call end() then receive an error
response to the unsubscribe.

It seems that the whole ClientSubscription usage needs a makeover.  : )

Scott

From: resiprocate-devel-bounces at resiprocate.org
[mailto:resiprocate-devel-bounces at resiprocate.org] On Behalf Of Aron
Rosenberg
Sent: July 14, 2008 7:20 PM
To: resiprocate-devel
Subject: Re: [reSIProcate] NULL Pointer crash with resip 1.3.3

I  was finally able to get a working pcap, resip log and debug crash at the
same time. Here is what is going on

1.       Client makes subscription

2.       Client ends the subscription by invoking end() on the handle

3.       This end results in a local 408 error, which calls onRequestRetry

4.       Our code returns 0 to onRequestRetry(ClientSubscriptionHandle) to
retry the request since we want the server to know we ended the sub

5.       "Application requested immediate retry on Retry-After" is printed
to log

6.       Crash happens in the else statement in ClientSubscription.cxx:198
when trying to call getAppDialogSet()->reuse().

I have a full log (over 100MB of resip data which I can send to a developer
who wants to look at it along with the matching pcap error file

-Aron

From: resiprocate-devel-bounces at resiprocate.org
[mailto:resiprocate-devel-bounces at resiprocate.org] On Behalf Of Aron
Rosenberg
Sent: Monday, July 14, 2008 2:17 PM
To: resiprocate-devel
Subject: Re: [reSIProcate] NULL Pointer crash with resip 1.3.3

Here is a little bit more information gleaned from a pcap trace.

The stack seems to be crashing when dealing with a 400 error where the
"From:" header looks like this

"From: <sip:>;tag=5b461e50"

I was able to find the outbound SUBSCRIBE request and it also has an empty
>From address so something strange is going on in the stack. Still working on
getting the resip logs.

-Aron

From: resiprocate-devel-bounces at resiprocate.org
[mailto:resiprocate-devel-bounces at resiprocate.org] On Behalf Of Aron
Rosenberg
Sent: Monday, July 14, 2008 11:50 AM
To: resiprocate-devel
Subject: [reSIProcate] NULL Pointer crash with resip 1.3.3

Resip ver: SVN rev 8128 on 1.3 branch

Call Stack: 

resip::AppDialogSet::getHandle() Line 22 + 0x3 bytes C++
resip::DialogUsage::getAppDialogSet() Line 38 + 0x18 bytes C++
resip::ClientSubscription::processResponse(const resip::SipMessage &
msg={...}) Line 198 + 0x12 bytes C++
resip::ClientSubscription::dispatch(const resip::SipMessage & msg={...})
Line 117 C++
resip::Dialog::dispatch(const resip::SipMessage & msg={...}) Line 651 + 0x1a
bytes C++
resip::DialogSet::dispatchToAllDialogs(const resip::SipMessage & msg={...})
Line 1028 C++
resip::DialogSet::dispatch(const resip::SipMessage & msg={...}) Line 608 C++
resip::DialogUsageManager::processResponse(const resip::SipMessage &
response={...}) Line 1810 C++
resip::DialogUsageManager::incomingProcess(std::auto_ptr<resip::Message>
msg=auto_ptr {tu=??? }) Line 1363 C++
resip::DialogUsageManager::internalProcess(std::auto_ptr<resip::Message>
msg=auto_ptr {tu=??? }) Line 1190 C++
resip::DialogUsageManager::process(resip::RWMutex * mutex=0x00000000) Line
1390 + 0x49 bytes C++
SipEP::run() Line 3408 + 0xa bytes C++

The crash is because the appDialogSet returned in
DialogUsage::getAppDialogSet() is NULL.

It came from our production client and is reasonable repeatable, so I am
working on getting the resip logs that would go with it.

-Aron

---------------------------------------------

Aron Rosenberg

Founder and CTO

SightSpeed - http://www.sightspeed.com/

918 Parker St, Suite A14

Berkeley, CA 94710

Email: arosenberg at sightspeed.com

Phone: 510-665-2920

Cell: 510-847-7389

Fax: 510-649-9569

SightSpeed Video Link: http://aron.sightspeed.com
<http://aron.sightspeed.com/> 

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