[PATCH AUTOSEL 6.1 19/61] drm/amdgpu: fix mc_data out-of-bounds read warning

From: Sasha Levin
Date: Wed Jul 31 2024 - 21:17:28 EST


From: Tim Huang <Tim.Huang@xxxxxxx>

[ Upstream commit 51dfc0a4d609fe700750a62f41447f01b8c9ea50 ]

Clear warning that read mc_data[i-1] may out-of-bounds.

Signed-off-by: Tim Huang <Tim.Huang@xxxxxxx>
Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c
index 9ba4817a91484..816014ea53817 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c
@@ -1476,6 +1476,8 @@ int amdgpu_atombios_init_mc_reg_table(struct amdgpu_device *adev,
(u32)le32_to_cpu(*((u32 *)reg_data + j));
j++;
} else if ((reg_table->mc_reg_address[i].pre_reg_data & LOW_NIBBLE_MASK) == DATA_EQU_PREV) {
+ if (i == 0)
+ continue;
reg_table->mc_reg_table_entry[num_ranges].mc_data[i] =
reg_table->mc_reg_table_entry[num_ranges].mc_data[i - 1];
}
--
2.43.0