diff mbox series

[v3] drm: Reject unknown legacy bpp and depth for drm_mode_addfb ioctl

Message ID 20180905153116.28924-1-chris@chris-wilson.co.uk (mailing list archive)
State New, archived
Headers show
Series [v3] drm: Reject unknown legacy bpp and depth for drm_mode_addfb ioctl | expand

Commit Message

Chris Wilson Sept. 5, 2018, 3:31 p.m. UTC
Since this is handling user provided bpp and depth, we need to sanity
check and propagate the EINVAL back rather than assume what the insane
client intended and fill the logs with DRM_ERROR.

v2: Check both bpp and depth match the builtin pixel format, and
introduce a canonical DRM_FORMAT_INVALID to reserve 0 against any future
fourcc.

v3: Mark up DRM_FORMAT_C8 as being {bpp:8, depth:8}

Testcase: igt/kms_addfb_basic/legacy-format
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
 drivers/gpu/drm/drm_fourcc.c      | 37 ++++++++++++++++++++++---------
 drivers/gpu/drm/drm_framebuffer.c |  7 +++++-
 include/uapi/drm/drm_fourcc.h     |  3 +++
 3 files changed, 36 insertions(+), 11 deletions(-)

Comments

Chris Wilson Sept. 6, 2018, 7:19 a.m. UTC | #1
Quoting Chris Wilson (2018-09-05 16:31:16)
> Since this is handling user provided bpp and depth, we need to sanity
> check and propagate the EINVAL back rather than assume what the insane
> client intended and fill the logs with DRM_ERROR.
> 
> v2: Check both bpp and depth match the builtin pixel format, and
> introduce a canonical DRM_FORMAT_INVALID to reserve 0 against any future
> fourcc.
> 
> v3: Mark up DRM_FORMAT_C8 as being {bpp:8, depth:8}
> 
> Testcase: igt/kms_addfb_basic/legacy-format
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Cc: Michel Dänzer <michel.daenzer@amd.com>
> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Pushed the sanity check. Hopefully we are all happy with
DRM_FORMAT_C8:          {bpp:8,  depth:8}
DRM_FORMAT_XRGB1555:    {bpp:16, depth:15}
DRM_FORMAT_RGB565:      {bpp:16, depth:16}
DRM_FORMAT_RGB888:      {bpp:24, depth:24}
DRM_FORMAT_XRGB8888:    {bpp:32, depth:24}
DRM_FORMAT_XRGB2101010: {bpp:32, depth:30}
DRM_FORMAT_ARGB8888:    {bpp:32, depth:32}

Thanks,
-Chris
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c
index 35c1e2742c27..be1d6aaef651 100644
--- a/drivers/gpu/drm/drm_fourcc.c
+++ b/drivers/gpu/drm/drm_fourcc.c
@@ -45,32 +45,49 @@  static char printable_char(int c)
  */
 uint32_t drm_mode_legacy_fb_format(uint32_t bpp, uint32_t depth)
 {
-	uint32_t fmt;
+	uint32_t fmt = DRM_FORMAT_INVALID;
 
 	switch (bpp) {
 	case 8:
-		fmt = DRM_FORMAT_C8;
+		if (depth == 8)
+			fmt = DRM_FORMAT_C8;
 		break;
+
 	case 16:
-		if (depth == 15)
+		switch (depth) {
+		case 15:
 			fmt = DRM_FORMAT_XRGB1555;
-		else
+			break;
+		case 16:
 			fmt = DRM_FORMAT_RGB565;
+			break;
+		default:
+			break;
+		}
 		break;
+
 	case 24:
-		fmt = DRM_FORMAT_RGB888;
+		if (depth == 24)
+			fmt = DRM_FORMAT_RGB888;
 		break;
+
 	case 32:
-		if (depth == 24)
+		switch (depth) {
+		case 24:
 			fmt = DRM_FORMAT_XRGB8888;
-		else if (depth == 30)
+			break;
+		case 30:
 			fmt = DRM_FORMAT_XRGB2101010;
-		else
+			break;
+		case 32:
 			fmt = DRM_FORMAT_ARGB8888;
+			break;
+		default:
+			break;
+		}
 		break;
+
 	default:
-		DRM_ERROR("bad bpp, assuming x8r8g8b8 pixel format\n");
-		fmt = DRM_FORMAT_XRGB8888;
 		break;
 	}
 
diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
index 781af1d42d76..636f626c5828 100644
--- a/drivers/gpu/drm/drm_framebuffer.c
+++ b/drivers/gpu/drm/drm_framebuffer.c
@@ -112,12 +112,17 @@  int drm_mode_addfb(struct drm_device *dev, struct drm_mode_fb_cmd *or,
 	struct drm_mode_fb_cmd2 r = {};
 	int ret;
 
+	r.pixel_format = drm_mode_legacy_fb_format(or->bpp, or->depth);
+	if (r.pixel_format == DRM_FORMAT_INVALID) {
+		DRM_DEBUG("bad (bpp:%d, depth:%d)\n", or->bpp, or->depth);
+		return -EINVAL;
+	}
+
 	/* convert to new format and call new ioctl */
 	r.fb_id = or->fb_id;
 	r.width = or->width;
 	r.height = or->height;
 	r.pitches[0] = or->pitch;
-	r.pixel_format = drm_mode_legacy_fb_format(or->bpp, or->depth);
 	r.handles[0] = or->handle;
 
 	if (r.pixel_format == DRM_FORMAT_XRGB2101010 &&
diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
index 2ed46e9ae16a..139632b87181 100644
--- a/include/uapi/drm/drm_fourcc.h
+++ b/include/uapi/drm/drm_fourcc.h
@@ -71,6 +71,9 @@  extern "C" {
 
 #define DRM_FORMAT_BIG_ENDIAN (1<<31) /* format is big endian instead of little endian */
 
+/* Reserve 0 for the invalid format specifier */
+#define DRM_FORMAT_INVALID	0
+
 /* color index */
 #define DRM_FORMAT_C8		fourcc_code('C', '8', ' ', ' ') /* [7:0] C */