The png_destroy_write_struct() function frees all memory used by
libpng. Don't use the glib auto cleanup mechanism to free the
memory allocated by libpng again. For the pixman image, use only the
auto cleanup mechanism and remove the qemu_pixman_image_unref()
function call to prevent another double free.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1210
Fixes: 9a0a119a38 ("Added parameter to take screenshot with screendump as PNG")
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20220919061956.30929-1-vr_qemu@t-online.de>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
17b55372b5