[Varnish] #1762: VSL API: endless loop and out of memory in vtx_scan() on forced synthetic transactions

[Varnish]

#1762: VSL API: endless loop and out of memory in vtx_scan() on forced synthetic
transactions
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 Reporter:  geoff     |       Owner:
     Type:  defect    |      Status:  reopened
 Priority:  normal    |   Milestone:  Varnish 4.0 release
Component:  varnishd  |     Version:  4.0.3
 Severity:  critical  |  Resolution:
 Keywords:            |
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Changes (by geoff):

 * status:  closed => reopened
 * resolution:  fixed =>


Comment:

 This problem is not solved, since the endless loop and ENOMEM could happen
 again if a VXID mismatch occurs for any other reason.

 It's good to have the fix backported to 4.0, that would remove the
 specific cause of the problem that we experienced recently.

 But I assume that the check for VXID mismatch is there on the assumption
 that it might possibly happen, and if it does, I don't see how the same
 showstopper can be avoided.

 If we're certain that the VXID mismatch cannot happen under any
 circumstances now, then we should remove the check. But we certainly
 should not leave a ticking time bomb in the code.

-- 
Ticket URL: <https://www.varnish-cache.org/trac/ticket/1762#comment:3>
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