[Varnish] #1630: Varnish crashes with long regex condition

[Varnish]

#1630: Varnish crashes with long regex condition
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 Reporter:  huguesalary  |       Owner:  Tollef Fog Heen <tfheen@…>
     Type:  defect       |      Status:  closed
 Priority:  normal       |   Milestone:
Component:  varnishd     |     Version:  4.0.2
 Severity:  normal       |  Resolution:  fixed
 Keywords:               |
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Comment (by paluna):

 Thanks for the suggestions.

 I will submit a new (full) crash dump and config files as soon as a new
 crash happens again. Note that it only crashes about once a month which
 makes it difficult. At that point I will share my main VCL as well.

 0. I have now changed the core file size to unlimited for the varnish
 processes.

 1. I cannot reproduce it either (not in production, not in the dev
 environment). The server handles on avg 125K requests/day and I cannot
 figure out which http request/response causes the crash; maybe it is not
 related to a specific http req/rsp at all, who knows. The varnish daemon
 is also restarted once every night at 4am in the production environment.
 The varnishlog is empty after the crash because the varnishd has been
 restarted.

 2. There is nothing else in syslog. I did not run varnishadm panic.show at
 the time of the crash.

 3. Yes, it is installed from "deb https://repo.varnish-cache.org/ubuntu/
 trusty varnish-4.1".

 4. The server only imports 1 VMODs, being std.

 5. The server config includes a computer generated vcl script with lots of
 regexp's to detect mobile devices
 https://gist.github.com/pantaluna/029741e2f299415eceec



 Replying to [comment:8 fgsch]:
 > Can you enable coredumps (e.g. ulimit -c unlimited)?
 > When it crashes is there anything else under syslog or varnishadm
 panic.show?
 > Are you using any VMODs besides std? Is varnish installed from repo
 .varnish-cache.org?
 >
 > Sharing your VCL might also help.
 >
 > There is no much info in the crashdump and I cannot reproduce it using
 your pcre limits.

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Ticket URL: <https://www.varnish-cache.org/trac/ticket/1630#comment:9>
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