nginx dso coredump

[Maxim Dounin]

Hello!

On Tue, Aug 30, 2016 at 06:33:36PM +0800, 洪志道 wrote:


[...]

> I found a coredump file generated on production.

[...]

> nginx.conf
> 
> load_module  modules/....;
> load_module  modules/ngx_http_abc_module_3.so;  # This module is in the
> last postion, the other modules seems right.
> 
> And there is tiny detail. I generate so file named
> 'ngx_http_abc_module.so', then I copy as ngx_http_abc_module_3.so

Note that when writing module *.so files care should be taken to 
not modify contents of files currently loaded.  E.g., "make 
install" in nginx will first move an old file (if any) to 
*.so.old, and then copy the new file.

If you happened to modify an *.so file currently loaded, 
segmentation fault is expected.  Just using "cp" without moving an 
old file first is known to cause segmentation faults as it 
modifies contents of existing *.so files.

-- 
Maxim Dounin
http://nginx.org/