[PATCH] drm/nouveau/dispnv04: fix null pointer dereference in nv17_tv_get_hd_modes

[Markus Elfring]

> In nv17_tv_get_hd_modes(), the return value of drm_mode_duplicate() is
> assigned to mode, which will lead to a possible NULL pointer dereference
> on failure of drm_mode_duplicate(). The same applies to drm_cvt_mode().
> Add a check to avoid null pointer dereference.

Can a wording approach (like the following) be a better change description?

  A null pointer is stored in the local variable “mode” after a call
  of the function “drm_cvt_mode” or “drm_mode_duplicate” failed.
  This pointer was used in subsequent statements where an undesirable
  dereference will be performed then.
  Thus add corresponding return value checks.


> Cc: stable at vger.kernel.org

Would you like to add the tag “Fixes” accordingly?


How do you think about to use a summary phrase like
“Prevent null pointer dereferences in nv17_tv_get_hd_modes()”?

Regards,
Markus