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Potential BLODA issue with commercial file encryption tool




Dear Cygwin folks,

there seems to be a BLODA issue between Cygwin and a commercial file encryption tool named "fideAS file enterprise". Since this tool was upgraded from version 6.4.0.12 to 7.1.0.8 on some computers, errors like the following started to occur. Some applications (like tmux) always reproducibly fail to start, others  (like bash) sometimes succeed and sometimes do not, depending on the circumstances that I have not figured out exactly yet.

--- cut ---
$ tmux
0 [main] tmux 8916 fork: child 9156 - died waiting for dll loading, errno 11
--- cut ---

In the DLL view of Sysinterals Process Explorer, I see a file named "asCryptoFilter64.dll" being loaded into bash.exe, mintty.exe and others. Note that there are two processes running related to fideAS, namely  "ffPrivateAgent.exe" and "loadFilter.exe" . Killing them does not prevent the aforementioned DLL from being loaded into newly created processes, even if the process creation takes place after killing the two processes (how does this work, by the way?). The error also remains after killing these two processes.

Note that when the Cygwin terminal is run as administrator, asCryptoFilter64.dll does not appear in the Process Explorer DLL list, and tmux works. I just figured that out right away when composing this mail.

What I have tried so far:
 * execute /usr/bin/rebase-trigger full, then re-run setup-x86_64.exe
   effect: tmux makes the terminal window hang when called.
   (I tried rebasing twice, both times led to the same result)

 * our IT department was in touch with the supplier of fideAS file enterprise. I was told that the Cygwin stack memory is too small (only approx. 1.8MB), and that usual applications have around 10MB. I did not have any context information, so I did - basically without knowing what is going on behind the scenes -:
--- cut ---
 1) create copy of cygwin directory to /cygdrive/d/cygwin64_copy in Windows Explorer
 2) find /cygdrive/d/cygwin64_copy \( -iname '*.exe' -o '*.dll' \) -exec peflags -X10485760 -x104857600 {} \;
 3) move original cygwin directory to /cygdrive/d/cygwin64_orig and /cygdrive/d/cygwin64_copy to original directory
 4) try running tmux: no effect
--- cut ---
This did not have any evident effect. I was told that re-compiling Cygwin with a compiler option to increase the stack size (I assume this would be -Wl,--stack,<size>) could solve the issue, but when the build process hung for several hours, I did not try this any further yet. Do you consider this an option worth trying?

 * I set the environment variable CYGWIN to detect_bloda, but did not learn anything from that (is this still active? https://cygwin.com/ml/cygwin-cvs/2016-q2/msg00135.html suggests it is not)

Note that the supplier has been working on this for more than a month now, but we neither have an ETA, nor feedback whether this can be fixed at all...
Does maybe someone here have an idea how to proceed any further?

Thank you very much in advance for your help!

Best regards,
Michael Weiner

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