On Wed, Nov 26, 2025 at 03:11:53PM +0300, Dan Carpenter wrote:
> The "cmd->in_offset" variable comes from the user via the __nd_ioctl()
> function. The problem is that the "cmd->in_offset + cmd->in_length"
> addition could have an integer wrapping issue if cmd->in_offset is close
> to UINT_MAX . Both "cmd->in_offset" and "cmd->in_length" are u32
> variables.
>
> Fixes: 43bc0aa19a21 ("nvdimm: allow exposing RAM carveouts as NVDIMM DIMM
> devices")
> Signed-off-by: Dan Carpenter <[email protected]>
Acked-by: Mike Rapoport (Microsoft) <[email protected]>
> ---
> v2: Ira Weiny pointed out that ramdax_set_config_data() needs to be
> fixed as well.
>
> drivers/nvdimm/ramdax.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/nvdimm/ramdax.c b/drivers/nvdimm/ramdax.c
> index 63cf05791829..954cb7919807 100644
> --- a/drivers/nvdimm/ramdax.c
> +++ b/drivers/nvdimm/ramdax.c
> @@ -143,7 +143,7 @@ static int ramdax_get_config_data(struct nvdimm *nvdimm,
> int buf_len,
> return -EINVAL;
> if (struct_size(cmd, out_buf, cmd->in_length) > buf_len)
> return -EINVAL;
> - if (cmd->in_offset + cmd->in_length > LABEL_AREA_SIZE)
> + if (size_add(cmd->in_offset, cmd->in_length) > LABEL_AREA_SIZE)
> return -EINVAL;
>
> memcpy(cmd->out_buf, dimm->label_area + cmd->in_offset, cmd->in_length);
> @@ -160,7 +160,7 @@ static int ramdax_set_config_data(struct nvdimm *nvdimm,
> int buf_len,
> return -EINVAL;
> if (struct_size(cmd, in_buf, cmd->in_length) > buf_len)
> return -EINVAL;
> - if (cmd->in_offset + cmd->in_length > LABEL_AREA_SIZE)
> + if (size_add(cmd->in_offset, cmd->in_length) > LABEL_AREA_SIZE)
> return -EINVAL;
>
> memcpy(dimm->label_area + cmd->in_offset, cmd->in_buf, cmd->in_length);
> --
> 2.51.0
>
--
Sincerely yours,
Mike.
