From: Srinivasan Shanmugam srinivasan.shanmugam@amd.com

mainline inclusion from mainline-v6.12-rc1 commit 62ed6f0f198da04e884062264df308277628004f category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYR96 CVE: CVE-2024-49911

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

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This commit adds a null check for the set_output_gamma function pointer in the dcn20_set_output_transfer_func function. Previously, set_output_gamma was being checked for null at line 1030, but then it was being dereferenced without any null check at line 1048. This could potentially lead to a null pointer dereference error 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 at line 1048.

Cc: Tom Chung chiahsuan.chung@amd.com Cc: Rodrigo Siqueira Rodrigo.Siqueira@amd.com Cc: Roman Li roman.li@amd.com Cc: Alex Hung alex.hung@amd.com Cc: Aurabindo Pillai aurabindo.pillai@amd.com Cc: Harry Wentland harry.wentland@amd.com Cc: Hamza Mahfooz hamza.mahfooz@amd.com Signed-off-by: Srinivasan Shanmugam srinivasan.shanmugam@amd.com Reviewed-by: Tom Chung chiahsuan.chung@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Conflicts: drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c [commit e53524cdcc02 ("drm/amd/display: Refactor HWSS into component folder") is not backported, which moved dcn20_hwseq.c] Signed-off-by: Yu Kuai yukuai3@huawei.com --- drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c index c6c4888c6665..2248473a6a76 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c @@ -830,7 +830,8 @@ bool dcn20_set_output_transfer_func(struct dc *dc, struct pipe_ctx *pipe_ctx, /* * if above if is not executed then 'params' equal to 0 and set in bypass */ - 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 true; }