linux/drivers/gpu/drm/tilcdc
Ville Syrjälä 6185587b66 drm/tilcdc: Use drm_mode_copy()
struct drm_display_mode embeds a list head, so overwriting
the full struct with another one will corrupt the list
(if the destination mode is on a list). Use drm_mode_copy()
instead which explicitly preserves the list head of
the destination mode.

Even if we know the destination mode is not on any list
using drm_mode_copy() seems decent as it sets a good
example. Bad examples of not using it might eventually
get copied into code where preserving the list head
actually matters.

Obviously one case not covered here is when the mode
itself is embedded in a larger structure and the whole
structure is copied. But if we are careful when copying
into modes embedded in structures I think we can be a
little more reassured that bogus list heads haven't been
propagated in.

@is_mode_copy@
@@
drm_mode_copy(...)
{
...
}

@depends on !is_mode_copy@
struct drm_display_mode *mode;
expression E, S;
@@
(
- *mode = E
+ drm_mode_copy(mode, &E)
|
- memcpy(mode, E, S)
+ drm_mode_copy(mode, E)
)

@depends on !is_mode_copy@
struct drm_display_mode mode;
expression E;
@@
(
- mode = E
+ drm_mode_copy(&mode, &E)
|
- memcpy(&mode, E, S)
+ drm_mode_copy(&mode, E)
)

@@
struct drm_display_mode *mode;
@@
- &*mode
+ mode

Cc: Jyri Sarha <jyri.sarha@iki.fi>
Cc: Tomi Valkeinen <tomba@kernel.org>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220218100403.7028-17-ville.syrjala@linux.intel.com
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
2022-03-21 20:29:16 +02:00
..
Kconfig drm: Remove CONFIG_DRM_KMS_CMA_HELPER option 2021-11-30 11:10:03 +01:00
Makefile doc: use KCFLAGS instead of EXTRA_CFLAGS to pass flags from command line 2021-02-22 13:59:10 -07:00
tilcdc_crtc.c drm/tilcdc: Use drm_mode_copy() 2022-03-21 20:29:16 +02:00
tilcdc_drv.c drm/tilcdc: Add support for the nomodeset kernel parameter 2022-01-27 19:15:50 +01:00
tilcdc_drv.h drm/tilcdc: Convert to Linux IRQ interfaces 2021-08-10 20:13:53 +02:00
tilcdc_external.c drm/bridge: Centralize error message when bridge attach fails 2021-07-28 16:33:12 +03:00
tilcdc_external.h
tilcdc_panel.c drm/tilcdc: panel: fix platform_no_drv_owner.cocci warnings 2021-03-24 12:05:28 +02:00
tilcdc_panel.h
tilcdc_plane.c drm: Use state helper instead of the plane state pointer 2021-02-25 08:05:28 +01:00
tilcdc_regs.h