From: Alex Hung alex.hung@amd.com

stable inclusion from stable-v5.10.227 commit 8d54001f8dccd56146973f23f3ab2ba037a21251 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAZVX4 CVE: CVE-2024-49907

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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[ Upstream commit 95d9e0803e51d5a24276b7643b244c7477daf463 ]

[WHY & HOW] dc->clk_mgr is null checked previously in the same function, indicating it might be null.

Passing "dc" to "dc->hwss.apply_idle_power_optimizations", which dereferences null "dc->clk_mgr". (The function pointer resolves to "dcn35_apply_idle_power_optimizations".)

This fixes 1 FORWARD_NULL issue reported by Coverity.

Reviewed-by: Rodrigo Siqueira rodrigo.siqueira@amd.com Signed-off-by: Alex Hung alex.hung@amd.com Signed-off-by: Tom Chung chiahsuan.chung@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Guo Mengqi guomengqi3@huawei.com --- drivers/gpu/drm/amd/display/dc/core/dc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c index f1d84092f057..1a183eb0568b 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c @@ -3075,7 +3075,8 @@ void dc_allow_idle_optimizations(struct dc *dc, bool allow) if (allow == dc->idle_optimizations_allowed) return;

- if (dc->hwss.apply_idle_power_optimizations && dc->hwss.apply_idle_power_optimizations(dc, allow)) + if (dc->hwss.apply_idle_power_optimizations && dc->clk_mgr != NULL && + dc->hwss.apply_idle_power_optimizations(dc, allow)) dc->idle_optimizations_allowed = allow; }