git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From 62ed6f0f198da04e884062264df308277628004f Mon Sep 17 00:00:00 2001
   2 From: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
   3 Date: Wed, 31 Jul 2024 13:09:28 +0530
   4 Subject: drm/amd/display: Add NULL check for function pointer in dcn20_set_output_transfer_func
   5
   6 From: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
   7
   8 commit 62ed6f0f198da04e884062264df308277628004f upstream.
   9
  10 This commit adds a null check for the set_output_gamma function pointer
  11 in the dcn20_set_output_transfer_func function. Previously,
  12 set_output_gamma was being checked for null at line 1030, but then it
  13 was being dereferenced without any null check at line 1048. This could
  14 potentially lead to a null pointer dereference error if set_output_gamma
  15 is null.
  16
  17 To fix this, we now ensure that set_output_gamma is not null before
  18 dereferencing it. We do this by adding a null check for set_output_gamma
  19 before the call to set_output_gamma at line 1048.
  20
  21 Cc: Tom Chung <chiahsuan.chung@amd.com>
  22 Cc: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
  23 Cc: Roman Li <roman.li@amd.com>
  24 Cc: Alex Hung <alex.hung@amd.com>
  25 Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
  26 Cc: Harry Wentland <harry.wentland@amd.com>
  27 Cc: Hamza Mahfooz <hamza.mahfooz@amd.com>
  28 Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
  29 Reviewed-by: Tom Chung <chiahsuan.chung@amd.com>
  30 Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
  31 Signed-off-by: Sasha Levin <sashal@kernel.org>
  32 Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
  33 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  34 ---
  35  drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c |    3 ++-
  36  1 file changed, 2 insertions(+), 1 deletion(-)
  37
  38 --- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
  39 +++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
  40 @@ -856,7 +856,8 @@ bool dcn20_set_output_transfer_func(stru
  41         /*
  42          * if above if is not executed then 'params' equal to 0 and set in bypass
  43          */
  44 -       mpc->funcs->set_output_gamma(mpc, mpcc_id, params);
  45 +       if (mpc->funcs->set_output_gamma)
  46 +               mpc->funcs->set_output_gamma(mpc, mpcc_id, params);
  47
  48         return true;
  49  }