On 10/29/2024 3:29 AM, Li Huafei wrote:
> Fix the potential NULL pointer dereference on mem_ranges in
> amdgpu_discovery_get_nps_info(). Additionally, assign the output
> parameters nps_type and range_cnt after the kvzalloc() call to prevent
> modifying the output parameters in case of an error return.
>
> Fixes: b194d21b9bcc ("drm/amdgpu: Use NPS ranges from discovery table")
> Signed-off-by: Li Huafei <lihuaf...@huawei.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> index 4bd61c169ca8..1b1aedebb3c2 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> @@ -1757,11 +1757,13 @@ int amdgpu_discovery_get_nps_info(struct
> amdgpu_device *adev,
>
> switch (le16_to_cpu(nps_info->v1.header.version_major)) {
> case 1:
> - *nps_type = nps_info->v1.nps_type;
> - *range_cnt = nps_info->v1.count;
This one is used in the allocation call below. If you prefer to not
assign any of the out params before memory allocation is successful,
then use nps_info->v1.count in the alloc call.
Thanks for adding the alloc fail check.
Thanks,
Lijo
> mem_ranges = kvzalloc(
> *range_cnt * sizeof(struct amdgpu_gmc_memrange),
> GFP_KERNEL);
> + if (!mem_ranges)
> + return -ENOMEM;
> + *nps_type = nps_info->v1.nps_type;
> + *range_cnt = nps_info->v1.count;
> for (i = 0; i < *range_cnt; i++) {
> mem_ranges[i].base_address =
> nps_info->v1.instance_info[i].base_address;
