kasan_shadow_Nbyte_fill
kasan_shadow_Nbyte_fill(addr, size, KASAN_USE_AFTER_SCOPE);
kasan_shadow_Nbyte_fill(l, KASAN_ALLOCA_SCALE_SIZE, KASAN_STACK_LEFT);
kasan_shadow_Nbyte_fill(r, KASAN_ALLOCA_SCALE_SIZE, KASAN_STACK_RIGHT);
kasan_shadow_Nbyte_fill(stkbegin, size, 0);