Fixes out of array access
Fixes: b877a6b788a25c70e8b1d014f8628549/asan_heap-oob_1da2c3f_2324_5a1b329b0b3c4bb6b1d775660ac56717.r3d

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>