Patch "drm/amd/display: Add NULL check for function pointer in dcn32_set_output_transfer_func" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    drm/amd/display: Add NULL check for function pointer in dcn32_set_output_transfer_func

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-amd-display-add-null-check-for-function-pointer-.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit c3e3bcec2083c9e45a676cfccbb36f0ac397565e
Author: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>
Date:   Tue Nov 26 18:10:51 2024 +0800

    drm/amd/display: Add NULL check for function pointer in dcn32_set_output_transfer_func
    
    [ Upstream commit 28574b08c70e56d34d6f6379326a860b96749051 ]
    
    This commit adds a null check for the set_output_gamma function pointer
    in the dcn32_set_output_transfer_func function. Previously,
    set_output_gamma was being checked for null, but then it was being
    dereferenced without any null check. This could lead to a null pointer
    dereference if set_output_gamma is null.
    
    To fix this, we now ensure that set_output_gamma is not null before
    dereferencing it. We do this by adding a null check for set_output_gamma
    before the call to set_output_gamma.
    
    Cc: Tom Chung <chiahsuan.chung@xxxxxxx>
    Cc: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
    Cc: Roman Li <roman.li@xxxxxxx>
    Cc: Alex Hung <alex.hung@xxxxxxx>
    Cc: Aurabindo Pillai <aurabindo.pillai@xxxxxxx>
    Cc: Harry Wentland <harry.wentland@xxxxxxx>
    Cc: Hamza Mahfooz <hamza.mahfooz@xxxxxxx>
    Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>
    Reviewed-by: Tom Chung <chiahsuan.chung@xxxxxxx>
    Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
    Signed-off-by: Xiangyu Chen <xiangyu.chen@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_hwseq.c
index 650e1598bddcb..2289c17f6ead5 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_hwseq.c
@@ -587,7 +587,9 @@ bool dcn32_set_output_transfer_func(struct dc *dc,
 		}
 	}
 
-	mpc->funcs->set_output_gamma(mpc, mpcc_id, params);
+	if (mpc->funcs->set_output_gamma)
+		mpc->funcs->set_output_gamma(mpc, mpcc_id, params);
+
 	return ret;
 }