Segfault for loopback resolver

[Maxim Dounin]

Hello!

On Sun, Mar 21, 2010 at 04:21:38AM +0200, Marcus Clyne wrote:

> Hi,
> 
> With a standard (i.e. no options) installation of 0.8.34 on my Linux
> machine I get a segfault if the resolver named in the conf file is a
> loopback address/IP, but the resolver does not exist.  Other
> non-existing resolvers don't cause a problem (they just hang, and
> probably will time out), only loopback ones.
> 
> The debug log is :
> 

[...]

> 2010/03/21 04:07:30 [debug] 4287#0: *3 http cleanup add: 0000000001A44E60
> 2010/03/21 04:07:30 [debug] 4287#0: *3 http finalize request: -4, "/?" a:1, c:2

Could you please provide full debug log (i.e. switched on at global level, not
http/server/location)?  E.g. between the above lines should be some valuable
resolving information which isn't logged in request context but in global one
instead.

It should look like this:

...
2010/03/25 04:53:49 [debug] 86639#0: *1 http cleanup add: 0811F8F4
2010/03/25 04:53:49 [debug] 86639#0: malloc: 08126580:68
2010/03/25 04:53:49 [debug] 86639#0: resolve: "google.com"
2010/03/25 04:53:49 [debug] 86639#0: malloc: 0810D580:60
2010/03/25 04:53:49 [debug] 86639#0: malloc: 08133460:10
2010/03/25 04:53:49 [debug] 86639#0: malloc: 0810AD00:28
2010/03/25 04:53:49 [debug] 86639#0: resolve: "google.com" 12007
2010/03/25 04:53:49 [debug] 86639#0: UDP socket 11
2010/03/25 04:53:49 [debug] 86639#0: connect to 127.0.0.1:53, fd:11 #2
2010/03/25 04:53:49 [debug] 86639#0: kevent set event: 11: ft:-1 fl:0025
2010/03/25 04:53:49 [debug] 86639#0: send: fd:11 28 of 28
2010/03/25 04:53:49 [debug] 86639#0: malloc: 0810D640:60
2010/03/25 04:53:49 [debug] 86639#0: event timer add: -1: 30000:2466707655
2010/03/25 04:53:49 [debug] 86639#0: event timer add: -1: 5000:2466682655
2010/03/25 04:53:49 [debug] 86639#0: *1 http finalize request: -4, "/?" a:1, c:2
...

> 2010/03/21 04:07:30 [debug] 4287#0: *3 http request count:2 blk:0
> 2010/03/21 04:07:30 [debug] 4287#0: *3 http run request: "/?"
> 2010/03/21 04:07:30 [debug] 4287#0: *3 http upstream check client,
> write event:1, "/"
> 2010/03/21 04:07:30 [debug] 4287#0: *3 http upstream recv(): -1 (11:
> Resource temporarily unavailable)
> 2010/03/21 04:07:30 [alert] 4275#0: worker process 4287 exited on signal 11
> 
> 
> I've not got time to look into and write a patch for it right now,
> but will do if no-one gets around to it at some point.

Config and backtrace should be helpfull too.  Unfortunately I'm not able to
reproduce the problem.

Maxim Dounin