Error on security-hardened systems

[mardy]

Hi!
I'm running isso (which depends on misaka) in dreamhost. Since a couple of months my isso CGI stopped working:

$ ~/mardy.it/cgi-bin/isso.fcgi 
Traceback (most recent call last):
  File "/home/mardy/mardy.it/cgi-bin/isso.fcgi", line 7, in <module>
    from isso import make_app
  File "/home/mardy/isso/lib/python3.6/site-packages/isso/__init__.py", line 72, in <module>
    from isso.utils import http, JSONRequest, html, hash
  File "/home/mardy/isso/lib/python3.6/site-packages/isso/utils/html.py", line 6, in <module>
    import misaka
  File "/home/mardy/isso/lib/python3.6/site-packages/misaka/__init__.py", line 3, in <module>
    from .api import *
  File "/home/mardy/isso/lib/python3.6/site-packages/misaka/api.py", line 10, in <module>
    from .callbacks import python_callbacks, to_string
  File "/home/mardy/isso/lib/python3.6/site-packages/misaka/callbacks.py", line 8, in <module>
    @ffi.callback('void(hoedown_buffer *ob, const hoedown_buffer *text, '
MemoryError: Cannot allocate write+execute memory for ffi.callback(). You might be running on a system that prevents this. For more information, see https://cffi.readthedocs.io/en/latest/using.html#callbacks

I understand that this will be eventually solved by #69, but I wonder if you are aware of a quicker workaround to get things working?

[FSX]

Hi, thanks for the report! Do you have more details about the system you're running? Then I can reproduce the issue and see what I can do.

…

----- Original message ----- From: Alberto Mardegan <[email protected]> To: FSX/misaka <[email protected]> Cc: Subscribed <[email protected]> Subject: [FSX/misaka] Error on security-hardened systems (#72) Date: Friday, September 06, 2019 16:51 Hi! I'm running isso (which depends on misaka) in dreamhost. Since a couple of months my isso CGI stopped working: `$ ~/mardy.it/cgi-bin/isso.fcgi Traceback (most recent call last): File "/home/mardy/mardy.it/cgi-bin/isso.fcgi", line 7, in <module> from isso import make_app File "/home/mardy/isso/lib/python3.6/site-packages/isso/__init__.py", line 72, in <module> from isso.utils import http, JSONRequest, html, hash File "/home/mardy/isso/lib/python3.6/site-packages/isso/utils/html.py", line 6, in <module> import misaka File "/home/mardy/isso/lib/python3.6/site-packages/misaka/__init__.py", line 3, in <module> from .api import * File "/home/mardy/isso/lib/python3.6/site-packages/misaka/api.py", line 10, in <module> from .callbacks import python_callbacks, to_string File "/home/mardy/isso/lib/python3.6/site-packages/misaka/callbacks.py", line 8, in <module> @ffi.callback('void(hoedown_buffer *ob, const hoedown_buffer *text, ' MemoryError: Cannot allocate write+execute memory for ffi.callback(). You might be running on a system that prevents this. For more information, see https://cffi.readthedocs.io/en/latest/using.html#callbacks ` I understand that this will be eventually solved by #69 <#69>, but I wonder if you are aware of a quicker workaround to get things working? — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#72?email_source=notifications&email_token=AAAPWEPYX4YMDEOSGLAMP5LQIJU7HA5CNFSM4IUJ4ML2YY3PNVWWK3TUL52HS4DFUVEXG43VMWVGG33NNVSW45C7NFSM4HJ2OVUQ>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAAPWEPN3V2TQH6BTIF2VMLQIJU7HANCNFSM4IUJ4MLQ>.

[mardy]

Hi, thanks for the report! Do you have more details about the system you're running? Then I can reproduce the issue and see what I can do.

Not really, but the page linked in the error message has some informative recommendation:

To fix the issue once and for all on the affected platforms, you need to refactor the involved code so that it no longer uses ffi.callback().

For the time being, I've "fixed" the issue by making isso use mark3 instead of misaka, just on my own hosting.

[FSX]

Alright. I'll take a look at it once I get home. 👍

----- Original message ----- From: Alberto Mardegan <[email protected]> To: FSX/misaka <[email protected]> Cc: Frank <[email protected]>, Comment <[email protected]> Subject: Re: [FSX/misaka] Error on security-hardened systems (#72) Date: Friday, September 06, 2019 17:13

Hi, thanks for the report! Do you have more details about the system you're running? Then I can reproduce the issue and see what I can do.

Not really, but the page <https://cffi.readthedocs.io/en/latest/using.html#callbacks> linked in the error message has some informative recommendation:

To fix the issue once and for all on the affected platforms, you need to refactor the involved code so that it no longer uses ffi.callback().

For the time being, I've "fixed" the issue by making isso use mark3 instead of misaka, just on my own hosting. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#72?email_source=notifications&email_token=AAAPWEMTEHPWOQXXGJNWNNLQIJXQHA5CNFSM4IUJ4ML2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD6DEWLQ#issuecomment-528894766>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAAPWEOB4EJLP4BEJVLXJU3QIJXQHANCNFSM4IUJ4MLQ>.

[FSX]

@mardy Can you give this branch https://github.com/FSX/misaka/tree/cffi-new-style-callbacks a try?

[mardy]

Wow, that was fast! Works like a charm :-)

[FSX]

Good. I'll make a release shortly (and then close this issue).