1. 12 Apr, 2022 2 commits
    • Ville Syrjälä's avatar
      drm: Use drm_mode_copy() · a3342f4d
      Ville Syrjälä authored
      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
      Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
      Link: https://patchwork.freedesktop.org/patch/msgid/20220218100403.7028-23-ville.syrjala@linux.intel.comReviewed-by: default avatarAndrzej Hajda <andrzej.hajda@intel.com>
      a3342f4d
    • Ville Syrjälä's avatar
      drm: Use drm_mode_init() for on-stack modes · 563c4a75
      Ville Syrjälä authored
      Initialize on-stack modes with drm_mode_init() to guarantee
      no stack garbage in the list head, or that we aren't copying
      over another mode's list head.
      
      Based on the following cocci script, with manual fixups:
      @decl@
      identifier M;
      expression E;
      @@
      - struct drm_display_mode M = E;
      + struct drm_display_mode M;
      
      @@
      identifier decl.M;
      expression decl.E;
      statement S, S1;
      @@
      struct drm_display_mode M;
      ... when != S
      + drm_mode_init(&M, &E);
      +
      S1
      
      @@
      expression decl.E;
      @@
      - &*E
      + E
      Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
      Link: https://patchwork.freedesktop.org/patch/msgid/20220218100403.7028-22-ville.syrjala@linux.intel.comReviewed-by: default avatarAndrzej Hajda <andrzej.hajda@intel.com>
      563c4a75
  2. 11 Apr, 2022 9 commits
  3. 08 Apr, 2022 9 commits
  4. 07 Apr, 2022 20 commits