In the minimal pixman API stub that is used when the real pixman
dependency is missing a NULL dereference happens when
virtio-gpu-rutabaga allocates a pixman image with bits = NULL and
rowstride_bytes = zero. A buffer of rowstride_bytes * height is
allocated which is NULL. However, in that scenario pixman calculates a
new stride value based on given width, height and format size.
This commit adds a helper function that performs the same logic as
pixman.
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20231121093840.2121195-1-manos.pitsidianakis@linaro.org>
e0c58720bf