@linuxmaniac - that is not solving it, setting ptr to NULL is effective only inside the curl_shm_free().
To me it looks like some pointers that are given to a CURL function, which is going to free them at some point, are also freed inside http_async_client module. Not that familiar with the code, but I think some of the `shm_free(`) inside `set_query_params()` should not be done. I guess that the fix is in the direction of: when a field from `struct query_params` is given to a CURL function, it should be set to `NULL` so `set_query_params()` doesn't free it again. Now, identifying when the field is given to a CURL function requires to look deeper a the code of the module, not being familiar with, I couldn't do it quickly and no much spare time here at this moment.