CVE-2025-71138

In the Linux kernel, the following vulnerability has been resolved:

drm/msm/dpu: Add missing NULL pointer check for pingpong interface

It is checked almost always in dpu_encoder_phys_wb_setup_ctl(), but in a
single place the check is missing.
Also use convenient locals instead of phys_enc->* where available.

Patchwork: https://patchwork.freedesktop.org/patch/693860/

• https://git.kernel.org/stable/c/35ea3282136a630a3fd92b76f5a3a02651145ef1

  416baaa9-dc9f-4396-8d5f-8c081fb06d67
• https://git.kernel.org/stable/c/471baae774a30a04cf066907b60eaf3732928cb7

  416baaa9-dc9f-4396-8d5f-8c081fb06d67
• https://git.kernel.org/stable/c/678d1c86566dfbb247ba25482d37fddde6140cc9

  416baaa9-dc9f-4396-8d5f-8c081fb06d67
• https://git.kernel.org/stable/c/88733a0b64872357e5ecd82b7488121503cb9cc6

  416baaa9-dc9f-4396-8d5f-8c081fb06d67