tree 29b3c6a55851b2036f9f2529b61fead86002dc26
parent 47b1a541cb1943d85da3976b93f9a5ed490288e2
author Anuj Verma <anujv@iitbhilai.ac.in> 1627873843 +0530
committer Werner Lemberg <wl@gnu.org> 1627876275 +0200

Fix invalid memory access in `bsdf` rasterizer.

Do not generate SDF from bitmap if the `FT_GLYPH_OWN_BITMAP` flag is not
set.  In some cases the bitmap buffer is freed but still points to a valid
address; to handle those cases check the flag before accessing the memory.

* src/sdf/ftsdfrend.c (ft_bsdf_render): Handle the above case.
Also, return an error message if the bitmap's rows/pitch is invalid,
otherwise `slot->buffer` might be assigned to some invalid memory location.
(ft_sdf_render): Same as above.
Plus, move the outline back to original state after rasterization and not if
any error occurs.

Signed-off-by: Anuj Verma <anujv@iitbhilai.ac.in>