Bug#900821: linux-image-4.9.0-6-amd64: apache reads wrong data over cifs filesystems served by samba

["Troxler, Ciril" <ciril.troxler@komaxgroup.com>]

Package: src:linux
Version: 4.9.82-1+deb9u3

Dear Maintainer,

while we were investigating a problem, we found that we are affected by this bug.
We found some information you might find useful:

Another workaround than using an older kernel is to set the EnableSendFile directive to on.
http://httpd.apache.org/docs/2.4/mod/core.html#EnableSendfile

Without this setting, about 1/3 of the results are correct.
Mostly there are a few wrong results that are served more than once.

$ for i in {1..100} ; do wget -O- http://localhost/file | md5sum ; done | sort | uniq -c | sort -r
     27 ca1014c32a2074b10b94461c1aa121d0  -
      4 01e4b0e9bc0666697f6494e93ea03c67  -
      2 77a39ffc2021e92e43d7b0320aa24d31  -
      2 3ea2b0369a4357b7343304760c9a604b  -
      1 fe2918ea421b449f66c70472b4becfb5  -
      1 fc5a29070cb70371ecb235e56d372d9d  -
      ...

Regards.

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