wayland: Seal SHM buffers before access

If wayland client lies about size of given buffer, compositor could touch bad
memory and get SIGBUS. Wayland provides simple API to fix it - so fix it!

[1] http://cgit.freedesktop.org/wayland/wayland/tree/src/wayland-server.h#n416
[2] http://lists.freedesktop.org/archives/wayland-devel/2013-November/012159.html

Signed-off-by: Marek Chalupa <mchqwerty@gmail.com>

https://bugzilla.gnome.org/show_bug.cgi?id=727893
This commit is contained in:
Marek Chalupa
2015-01-09 16:09:23 +01:00
committed by Jasper St. Pierre
parent 87eb5f8632
commit b6d070b06f
2 changed files with 18 additions and 0 deletions

View File

@ -317,6 +317,8 @@ meta_cursor_image_load_from_buffer (MetaCursorImage *image,
{
int rowstride = wl_shm_buffer_get_stride (shm_buffer);
wl_shm_buffer_begin_access (shm_buffer);
switch (wl_shm_buffer_get_format (shm_buffer))
{
#if G_BYTE_ORDER == G_BIG_ENDIAN
@ -344,6 +346,8 @@ meta_cursor_image_load_from_buffer (MetaCursorImage *image,
(uint8_t *) wl_shm_buffer_get_data (shm_buffer),
width, height, rowstride,
gbm_format);
wl_shm_buffer_end_access (shm_buffer);
}
else
{