mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-03 18:20:25 +02:00 
			
		
		
		
	drm/fence: fix memory overwrite when setting out_fence fd
Currently if the userspace declares a int variable to store the out_fence
fd and pass it to OUT_FENCE_PTR the kernel will overwrite the 32 bits
above the int variable on 64 bits systems.
Fix this by making the internal storage of out_fence in the kernel a s32
pointer.
Reported-by: Chad Versace <chadversary@chromium.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Fixes: beaf5af480 ("drm/fence: add out-fences support")
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Rafael Antognolli <rafael.antognolli@intel.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-and-Tested-by: Chad Versace <chadversary@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1484317329-9293-1-git-send-email-gustavo@padovan.org
			
			
This commit is contained in:
		
							parent
							
								
									3846fd9b86
								
							
						
					
					
						commit
						7e9081c5aa
					
				
					 3 changed files with 8 additions and 8 deletions
				
			
		| 
						 | 
				
			
			@ -291,15 +291,15 @@ drm_atomic_get_crtc_state(struct drm_atomic_state *state,
 | 
			
		|||
EXPORT_SYMBOL(drm_atomic_get_crtc_state);
 | 
			
		||||
 | 
			
		||||
static void set_out_fence_for_crtc(struct drm_atomic_state *state,
 | 
			
		||||
				   struct drm_crtc *crtc, s64 __user *fence_ptr)
 | 
			
		||||
				   struct drm_crtc *crtc, s32 __user *fence_ptr)
 | 
			
		||||
{
 | 
			
		||||
	state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = fence_ptr;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static s64 __user *get_out_fence_for_crtc(struct drm_atomic_state *state,
 | 
			
		||||
static s32 __user *get_out_fence_for_crtc(struct drm_atomic_state *state,
 | 
			
		||||
					  struct drm_crtc *crtc)
 | 
			
		||||
{
 | 
			
		||||
	s64 __user *fence_ptr;
 | 
			
		||||
	s32 __user *fence_ptr;
 | 
			
		||||
 | 
			
		||||
	fence_ptr = state->crtcs[drm_crtc_index(crtc)].out_fence_ptr;
 | 
			
		||||
	state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = NULL;
 | 
			
		||||
| 
						 | 
				
			
			@ -512,7 +512,7 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
 | 
			
		|||
		state->color_mgmt_changed |= replaced;
 | 
			
		||||
		return ret;
 | 
			
		||||
	} else if (property == config->prop_out_fence_ptr) {
 | 
			
		||||
		s64 __user *fence_ptr = u64_to_user_ptr(val);
 | 
			
		||||
		s32 __user *fence_ptr = u64_to_user_ptr(val);
 | 
			
		||||
 | 
			
		||||
		if (!fence_ptr)
 | 
			
		||||
			return 0;
 | 
			
		||||
| 
						 | 
				
			
			@ -1915,7 +1915,7 @@ EXPORT_SYMBOL(drm_atomic_clean_old_fb);
 | 
			
		|||
 */
 | 
			
		||||
 | 
			
		||||
struct drm_out_fence_state {
 | 
			
		||||
	s64 __user *out_fence_ptr;
 | 
			
		||||
	s32 __user *out_fence_ptr;
 | 
			
		||||
	struct sync_file *sync_file;
 | 
			
		||||
	int fd;
 | 
			
		||||
};
 | 
			
		||||
| 
						 | 
				
			
			@ -1952,7 +1952,7 @@ static int prepare_crtc_signaling(struct drm_device *dev,
 | 
			
		|||
		return 0;
 | 
			
		||||
 | 
			
		||||
	for_each_crtc_in_state(state, crtc, crtc_state, i) {
 | 
			
		||||
		u64 __user *fence_ptr;
 | 
			
		||||
		s32 __user *fence_ptr;
 | 
			
		||||
 | 
			
		||||
		fence_ptr = get_out_fence_for_crtc(crtc_state->state, crtc);
 | 
			
		||||
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
| 
						 | 
				
			
			@ -144,7 +144,7 @@ struct __drm_crtcs_state {
 | 
			
		|||
	struct drm_crtc *ptr;
 | 
			
		||||
	struct drm_crtc_state *state;
 | 
			
		||||
	struct drm_crtc_commit *commit;
 | 
			
		||||
	s64 __user *out_fence_ptr;
 | 
			
		||||
	s32 __user *out_fence_ptr;
 | 
			
		||||
};
 | 
			
		||||
 | 
			
		||||
struct __drm_connnectors_state {
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
| 
						 | 
				
			
			@ -488,7 +488,7 @@ struct drm_mode_config {
 | 
			
		|||
	/**
 | 
			
		||||
	 * @prop_out_fence_ptr: Sync File fd pointer representing the
 | 
			
		||||
	 * outgoing fences for a CRTC. Userspace should provide a pointer to a
 | 
			
		||||
	 * value of type s64, and then cast that pointer to u64.
 | 
			
		||||
	 * value of type s32, and then cast that pointer to u64.
 | 
			
		||||
	 */
 | 
			
		||||
	struct drm_property *prop_out_fence_ptr;
 | 
			
		||||
	/**
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
		Loading…
	
		Reference in a new issue