Coming back to the original patch.
Am 08.04.25 um 11:17 schrieb Denis Arefev:
> The user can set any value to the variable ‘bo_number’, via the ioctl
> command DRM_IOCTL_AMDGPU_BO_LIST. This will affect the arithmetic
> expression ‘in->bo_number * in->bo_info_size’, which is prone to
> overflow. Add a valid value check.
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Fixes: 964d0fbf6301 ("drm/amdgpu: Allow to create BO lists in CS ioctl v3")
> Cc: sta...@vger.kernel.org
> Signed-off-by: Denis Arefev <are...@swemel.ru>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
> index 702f6610d024..dd30d2426ff7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
> @@ -189,6 +189,9 @@ int amdgpu_bo_create_list_entry_array(struct
> drm_amdgpu_bo_list_in *in,
> struct drm_amdgpu_bo_list_entry *info;
> int r;
>
> + if (!in->bo_number || in->bo_number > UINT_MAX / info_size)
> + return -EINVAL;
> +
As discussed with Linus the goal here is not to avoid the warning, but rather
to apply a reasonable limit.
Since we already use an u16 for the number of BOs in other cases it is probably
reasonable to assume that we will never have more than USHRT_MAX number of BOs
here as well.
So please change the patch accordingly and hopefully nobody will complain.
Regards,
Christian.
> info = kvmalloc_array(in->bo_number, info_size, GFP_KERNEL);
> if (!info)
> return -ENOMEM;
