possible memory leak / missing free

[Pavol Rusnak]

We've received the following report from a reporter:
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For source code file sK1-0.9.1pre/src/extentions/skmod/curveobject.c
around line 1450, function curve_parse_string_append is the following code

   old_locale = strdup(setlocale(LC_NUMERIC, NULL));

but for the success return, I fail to notice a matching call to free.
There is a call to free for the fail return. This looks like
a memory leak to me. Suggest add call to free on the success return.