dovecot - Mar 2016 - sis deduplication broken from 2.2.16 upwards

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Hi,

sis attachment deduplication is broken in 2.2.16 upwards.
It is caused by this commit.
https://github.com/dovecot/core/commit/664bf3e236c214aee86294483c379e4fa66c2e63

in src/lib-fs/fs-sis.c function fs_sis_try_link() is comparation of
inodes of hash files.
Because fs_stat() after that commit use fstat() on open fd of temporary
file instead of stat on filename. But that temporary file has differnt
inode.

It not cause any corruption but it will not save any space.
Because every duplicate attachment will be in separate file.

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Pavel Stano | Troubleshooter

http://WebSupport.sk
*** BERTE A VYCHUTNAVAJTE ***

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On 08 Mar 2016, at 01:50, Pavel Stano <stanojr at websupport.sk>
wrote:
> 
> 
> sis attachment deduplication is broken in 2.2.16 upwards.
> It is caused by this commit.
>
https://github.com/dovecot/core/commit/664bf3e236c214aee86294483c379e4fa66c2e63
> 
> in src/lib-fs/fs-sis.c function fs_sis_try_link() is comparation of
> inodes of hash files.
> Because fs_stat() after that commit use fstat() on open fd of temporary
> file instead of stat on filename. But that temporary file has differnt
> inode.
> 
> It not cause any corruption but it will not save any space.
> Because every duplicate attachment will be in separate file.
Thanks, fixed:
https://github.com/dovecot/core/commit/3b39022ea0513363241cf852b7d454c841584ea1

On 3/9/2016 9:02 PM, Timo Sirainen <tss at iki.fi>
wrote:
> On 08 Mar 2016, at 01:50, Pavel Stano <stanojr at websupport.sk>
wrote:
>>
>> sis attachment deduplication is broken in 2.2.16 upwards.
>> It is caused by this commit.
>>
https://github.com/dovecot/core/commit/664bf3e236c214aee86294483c379e4fa66c2e63
>>
>> in src/lib-fs/fs-sis.c function fs_sis_try_link() is comparation of
>> inodes of hash files.
>> Because fs_stat() after that commit use fstat() on open fd of temporary
>> file instead of stat on filename. But that temporary file has differnt
>> inode.
>>
>> It not cause any corruption but it will not save any space.
>> Because every duplicate attachment will be in separate file.
> Thanks, fixed:
https://github.com/dovecot/core/commit/3b39022ea0513363241cf852b7d454c841584ea1
So, after the fix is applied, does dovecot silently delete the
duplicated files, or is there a command that needs to be run manually?