Only handle color planes that exist in a framebuffer's color format. Ignore non-existing planes.
So far, several helpers assumed that all 4 planes are available and silently ignored non-existing planes. This lead to subtil bugs with uninitialized data in instances of struct iosys_map. [1]
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Link: https://lore.kernel.org/dri-devel/20210730183511.20080-1-tzimmermann@suse.de... # 1 --- drivers/gpu/drm/drm_gem_atomic_helper.c | 6 ++-- drivers/gpu/drm/drm_gem_framebuffer_helper.c | 37 +++++++++++--------- include/drm/drm_gem_framebuffer_helper.h | 10 ++---- 3 files changed, 27 insertions(+), 26 deletions(-)
diff --git a/drivers/gpu/drm/drm_gem_atomic_helper.c b/drivers/gpu/drm/drm_gem_atomic_helper.c index a5026f617739..f16d60217c6c 100644 --- a/drivers/gpu/drm/drm_gem_atomic_helper.c +++ b/drivers/gpu/drm/drm_gem_atomic_helper.c @@ -169,8 +169,10 @@ int drm_gem_plane_helper_prepare_fb(struct drm_plane *plane, struct drm_gem_object *obj = drm_gem_fb_get_obj(state->fb, i); struct dma_fence *new;
- if (WARN_ON_ONCE(!obj)) - continue; + if (!obj) { + ret = -EINVAL; + goto error; + }
ret = dma_resv_get_singleton(obj->resv, usage, &new); if (ret) diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c b/drivers/gpu/drm/drm_gem_framebuffer_helper.c index 2fcacab9f812..09e90e19cd93 100644 --- a/drivers/gpu/drm/drm_gem_framebuffer_helper.c +++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c @@ -92,9 +92,9 @@ drm_gem_fb_init(struct drm_device *dev, */ void drm_gem_fb_destroy(struct drm_framebuffer *fb) { - size_t i; + unsigned int i;
- for (i = 0; i < ARRAY_SIZE(fb->obj); i++) + for (i = 0; i < fb->format->num_planes; i++) drm_gem_object_put(fb->obj[i]);
drm_framebuffer_cleanup(fb); @@ -329,24 +329,26 @@ EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_dirty); * The argument returns the addresses of the data stored in each BO. This * is different from @map if the framebuffer's offsets field is non-zero. * + * Both, @map and @data, must each refer to arrays with at least + * fb->format->num_planes elements. + * * See drm_gem_fb_vunmap() for unmapping. * * Returns: * 0 on success, or a negative errno code otherwise. */ -int drm_gem_fb_vmap(struct drm_framebuffer *fb, - struct iosys_map map[static DRM_FORMAT_MAX_PLANES], - struct iosys_map data[DRM_FORMAT_MAX_PLANES]) +int drm_gem_fb_vmap(struct drm_framebuffer *fb, struct iosys_map *map, + struct iosys_map *data) { struct drm_gem_object *obj; unsigned int i; int ret;
- for (i = 0; i < DRM_FORMAT_MAX_PLANES; ++i) { + for (i = 0; i < fb->format->num_planes; ++i) { obj = drm_gem_fb_get_obj(fb, i); if (!obj) { - iosys_map_clear(&map[i]); - continue; + ret = -EINVAL; + goto err_drm_gem_vunmap; } ret = drm_gem_vmap(obj, &map[i]); if (ret) @@ -354,7 +356,7 @@ int drm_gem_fb_vmap(struct drm_framebuffer *fb, }
if (data) { - for (i = 0; i < DRM_FORMAT_MAX_PLANES; ++i) { + for (i = 0; i < fb->format->num_planes; ++i) { memcpy(&data[i], &map[i], sizeof(data[i])); if (iosys_map_is_null(&data[i])) continue; @@ -385,10 +387,9 @@ EXPORT_SYMBOL(drm_gem_fb_vmap); * * See drm_gem_fb_vmap() for more information. */ -void drm_gem_fb_vunmap(struct drm_framebuffer *fb, - struct iosys_map map[static DRM_FORMAT_MAX_PLANES]) +void drm_gem_fb_vunmap(struct drm_framebuffer *fb, struct iosys_map *map) { - unsigned int i = DRM_FORMAT_MAX_PLANES; + unsigned int i = fb->format->num_planes; struct drm_gem_object *obj;
while (i) { @@ -442,13 +443,15 @@ int drm_gem_fb_begin_cpu_access(struct drm_framebuffer *fb, enum dma_data_direct { struct dma_buf_attachment *import_attach; struct drm_gem_object *obj; - size_t i; + unsigned int i; int ret;
- for (i = 0; i < ARRAY_SIZE(fb->obj); ++i) { + for (i = 0; i < fb->format->num_planes; ++i) { obj = drm_gem_fb_get_obj(fb, i); - if (!obj) - continue; + if (!obj) { + ret = -EINVAL; + goto err___drm_gem_fb_end_cpu_access; + } import_attach = obj->import_attach; if (!import_attach) continue; @@ -478,7 +481,7 @@ EXPORT_SYMBOL(drm_gem_fb_begin_cpu_access); */ void drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir) { - __drm_gem_fb_end_cpu_access(fb, dir, ARRAY_SIZE(fb->obj)); + __drm_gem_fb_end_cpu_access(fb, dir, fb->format->num_planes); } EXPORT_SYMBOL(drm_gem_fb_end_cpu_access);
diff --git a/include/drm/drm_gem_framebuffer_helper.h b/include/drm/drm_gem_framebuffer_helper.h index 1091e4fa08cb..d302521f3dd4 100644 --- a/include/drm/drm_gem_framebuffer_helper.h +++ b/include/drm/drm_gem_framebuffer_helper.h @@ -4,8 +4,6 @@ #include <linux/dma-buf.h> #include <linux/iosys-map.h>
-#include <drm/drm_fourcc.h> - struct drm_afbc_framebuffer; struct drm_device; struct drm_fb_helper_surface_size; @@ -39,11 +37,9 @@ struct drm_framebuffer * drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file, const struct drm_mode_fb_cmd2 *mode_cmd);
-int drm_gem_fb_vmap(struct drm_framebuffer *fb, - struct iosys_map map[static DRM_FORMAT_MAX_PLANES], - struct iosys_map data[DRM_FORMAT_MAX_PLANES]); -void drm_gem_fb_vunmap(struct drm_framebuffer *fb, - struct iosys_map map[static DRM_FORMAT_MAX_PLANES]); +int drm_gem_fb_vmap(struct drm_framebuffer *fb, struct iosys_map *map, + struct iosys_map *data); +void drm_gem_fb_vunmap(struct drm_framebuffer *fb, struct iosys_map *map); int drm_gem_fb_begin_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir); void drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir);