[PATCH 2/2] drm/amdgpu: fix mc_data out-of-bounds read warning

[Alex Deucher]

On Mon, May 6, 2024 at 5:37 AM Tim Huang <Tim.Huang at amd.com> wrote:
>
> Clear warning that read mc_data[i-1] may out-of-bounds.
>
> Signed-off-by: Tim Huang <Tim.Huang at amd.com>

Reviewed-by: Alex Deucher <alexander.deucher at amd.com>

> ---
>  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 52b12c1718eb..7dc102f0bc1d 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c
> @@ -1484,6 +1484,8 @@ 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];
>                                                                 }
> --
> 2.39.2
>