Fix segfault when using funpointer #511
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Modern CPUs restrict executing modifiable memory. Lib_ffi deals with this by mapping to copies of the closure object into memory. This change ensures that we use the executable copy for the function pointer.
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Many thanks for tracking down and fixing this problem, @tiash. The fix looks right to me, and I've confirmed that it addresses the issue on an SELinux system. |
This was referenced May 4, 2017
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This fixes the support for passing function pointers on platforms that use the no-exec bit in memory.
I believe this may be the underlying cause of issue ctypes #500, as we experienced the same issue when working on improvements for async_ssl.
The code was previously ignoring the function pointer provided by libffi and trying to executing the closure object directly (correct behavior for non no-exec platforms).