[BUG] 2.2.21 Panic: file imap-client.c: line 841 (client_check_command_hangs): assertion failed: (!have_wait_unfinished || unfinished_count > 0)

[Timo Sirainen]

On 04 Jan 2016, at 12:54, Timo Sirainen <tss at iki.fi> wrote:
> 
>> 
>> On 04 Jan 2016, at 09:58, Florian Pritz <bluewind at xinu.at> wrote:
>> 
>> On 04.01.2016 15:49, Timo Sirainen wrote:
>>> What about:
>>> 
>>>>> #5  0x000000000041dde6 in client_check_command_hangs (client=0x2363450) at imap-client.c:841
>>>>>      cmd = 0x0
>>>>>      unfinished_count = 0
>>>>>      have_wait_unfinished = true
>>>>>      __FUNCTION__ = "client_check_command_hangs"
>>> 
>>> Either the new code that's detecting hanging-bugs is somehow broken or it's actually preventing a hang by crashing instead, in which case the bug is elsewhere..
>> 
>> Output below.
>> 
>> Sending a private mail because I don't know what that session ID in the
>> output can be used for.
> 
> The session ID is harmless. Anyway, I'm having trouble figuring out how the crash could happen or how to reproduce it. According to the backtrace it seems like the client is running IDLE and then it sends "DONE\r\nNOOP\r\n" in same IP packet. But when doing that, I don't see a crash. Although during testing I did find several other bugs. Could you try patching and seeing if you still get the same crash after them? Or have you seen the crash after the initial few times?
> 
> https://github.com/dovecot/core/commit/1ddf959a750f3860feff4ab3f0e908f32740978f.diff
> https://github.com/dovecot/core/commit/c8e9fa2ffa2566e75f0500808b1bc9bf5d9db024.diff
> https://github.com/dovecot/core/commit/15307c2c91854e766bd9fb095d611a29b3f7572e.diff
> https://github.com/dovecot/core/commit/c7801f830c7d2e7d340065cdd5a5c795b1726223.diff

Actually, maybe this is enough:

https://github.com/dovecot/core/commit/f136b0050b3125b466af73984177250b7ed1a3be.diff

I still wasn't able to reproduce it though.