[PATCH v2 0/6] drm/rockchip: Fix error handling and resource leaks in Rockchip DRM drivers

[Jiaqi]

This is v2 of the patch series that was previously withdrawn due to
a critical bug in Patch 3/6.

Changes in v2:
  - Patch 3/6: Removed incorrect devm_free_irq() call in error path.
    The IRQ registered via devm_request_irq() is managed by devres and
    must NOT be manually freed. The corrected patch simply jumps to
    err_crtcs label for proper cleanup via vop2_destroy_crtcs().
  - Patch 5/6: Fixed trailing format issue that caused checkpatch ERROR.

This patch series fixes 6 bugs in the Rockchip DRM driver subsystem,
identified through static code analysis and confirmed by technical review.

The bugs range from Critical (of_node reference leaks, use-after-free)
to Medium (unchecked return values), and span 5 different source files.
Each patch addresses exactly one bug to facilitate review and bisection.

Summary of fixes:

  Patch 1/6 (Critical): Fix of_node reference leak in
    rockchip_drm_encoder_set_crtc_endpoint_id(). Both success and error
    paths leaked references acquired via of_graph helpers.

  Patch 2/6 (Critical): Fix dangling crtc->state in vop2_crtc_reset().
    kzalloc() failure left crtc->state as a use-after-free pointer.

  Patch 3/6 (High): Fix vop2_create_crtcs() error path cleanup in
    vop2_bind(). Failures returned directly without calling
    vop2_destroy_crtcs(), leaking of_node references. (v2: fixed
    double-free by removing manual devm_free_irq())

  Patch 4/6 (High): Fix vmap address caching in
    rockchip_gem_prime_vmap(). New vmap() results were not saved to
    rk_obj->kvaddr, causing repeated mappings and potential leaks.

  Patch 5/6 (High): Fix leaked vblank event in
    vop_crtc_atomic_disable(). Pending vop->event was warned but never
    sent, causing userspace hangs and vblank reference leaks. (v2:
    fixed checkpatch format error)

  Patch 6/6 (Medium): Check return value of cdn_dp_grf_write() in
    cdn_dp_enable_phy() error path. Ignored return value could leave
    GRF registers in an inconsistent state.

All patches have been verified against checkpatch.pl --strict.

Signed-off-by: Jiaqi <shijiaqi_develop at 163.com>
---
 drivers/gpu/drm/rockchip/cdn-dp-core.c       |  5 +++--
 drivers/gpu/drm/rockchip/rockchip_drm_drv.c  | 14 +++++++++----
 drivers/gpu/drm/rockchip/rockchip_drm_gem.c  |  1 +
 drivers/gpu/drm/rockchip/rockchip_drm_vop.c  | 11 ++++++++++-
 drivers/gpu/drm/rockchip/rockchip_drm_vop2.c |  2 +-
 5 files changed, 35 insertions(+), 9 deletions(-)