[Mlterm-dev-en] Can't Load im-uim: Dangling Pointer Dereference in im_uim.c

[Jun I. <jun...@gm...>]

I had problems using uim with mlterm, and I tracked the problem down
to an incorrect usage of uim_get_default_im_name() in
inputmethod/uim/im_uim.c.

The return value of uim_get_default_im_name(), assigned to a variable
named "engine", is being used as being indefinitely valid.  But every
call to a uim API can potentially free the buffer that
uim_get_default_im_name() returned, overwriting it with garbage.

The attached patch solves this problem by duplicating the string.
Since the duplication uses alloca(), I moved the invocation of
uim_get_default_im_name() back to im_uim_new(), where the copied
string is also needed.  Subseqent usage in uim_create_context() should
be fine, since this API copies (rather, interns) this argument.

2008-11-22  Jun Inoue  <jun...@gm...>

	* inputmethod/uim/im_uim.c: fix dangling pointer dereference that
	  can cause initialization to fail.