#12 Using dkim_options can leak memory

[Heath Morrison]

The function dkim_options, when used with DKIM_OPTS_SKIPHDRS or DKIM_OPTS_SIGNHDRS, can produce a memory leak. For example:

dkim_options(dkim_lib, DKIM_OP_SETOPT, DKIM_OPTS_SKIPHDRS, dkim_skip_headers, sizeof(char **));

Later, after calling dkim_close(), memory is not freed. The problem appears to be that dkim_options compiles regex's using regcomp() without later freeing them. If you call the following before dkim_close(), the memory is freed:

dkim_options(dkim_lib, DKIM_OP_SETOPT, DKIM_OPTS_SKIPHDRS, NULL, sizeof(char **));

This is because dkim_options with a NULL ptr value calls regfree(). The attached patch calls regfree() during dkim_close() on any regexes that were compiled for DKIM_OPTS_SKIPHDRS or DKIM_OPTS_SIGNHDRS.

[Heath Morrison]

Calls regfree() on regular expressions allocated by dkim_options()

[Anonymous]

Thanks for the patch!

This had already been discovered during an internal code audit, but the patched code has not yet been released.

I note you've upped the priority from the default. Are you in need of a patched release soon?

[Heath Morrison]

Thanks for your prompt response!

No, I don't need an immediate patched release. Thank you for caring, though :) I've patched my own release and can continue quite fine without an official release.

[Anonymous]

v2.8.3 released, containing this fix.