5.15-stable review patch. If anyone has any objections, please let me know.
------------------ From: Zack Rusin <[email protected]> commit a37ef7613c00f2d72c8fc08bd83fb6cc76926c8c upstream. Correctly set the length of the drm_event to the size of the structure that's actually used. The length of the drm_event was set to the parent structure instead of to the drm_vmw_event_fence which is supposed to be read. drm_read uses the length parameter to copy the event to the user space thus resuling in oob reads. Signed-off-by: Zack Rusin <[email protected]> Fixes: 8b7de6aa8468 ("vmwgfx: Rework fence event action") Reported-by: [email protected] # ZDI-CAN-23566 Cc: David Airlie <[email protected]> CC: Daniel Vetter <[email protected]> Cc: Zack Rusin <[email protected]> Cc: Broadcom internal kernel review list <[email protected]> Cc: [email protected] Cc: [email protected] Cc: <[email protected]> # v3.4+ Reviewed-by: Maaz Mombasawala <[email protected]> Reviewed-by: Martin Krastev <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/gpu/drm/vmwgfx/vmwgfx_fence.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/gpu/drm/vmwgfx/vmwgfx_fence.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_fence.c @@ -1068,7 +1068,7 @@ static int vmw_event_fence_action_create } event->event.base.type = DRM_VMW_EVENT_FENCE_SIGNALED; - event->event.base.length = sizeof(*event); + event->event.base.length = sizeof(event->event); event->event.user_data = user_data; ret = drm_event_reserve_init(dev, file_priv, &event->base, &event->event.base);
