On 1/8/19 6:24 PM, Dan Williams wrote:
> Kees reports a crash with the following signature...
>
> RIP: 0010:nvdimm_visible+0x79/0x80
> [..]
> Call Trace:
> internal_create_group+0xf4/0x380
> sysfs_create_groups+0x46/0xb0
> device_add+0x331/0x680
> nd_async_device_register+0x15/0x60
> async_run_entry_fn+0x38/0x100
>
> ...when starting a QEMU environment with "label-less" DIMM. Without
> labels QEMU does not publish any DSM methods. Without defined methods
> the NVDIMM_FAMILY type is not established and the nfit driver will skip
> registering security operations.
>
> In that case the security state should be initialized to a negative
> value in __nvdimm_create() and nvdimm_visible() should skip
> interrogating the specific ops. However, since 'enum
> nvdimm_security_state' was only defined to contain positive values the
> "if (nvdimm->sec.state < 0)" check always fails.
>
> Define a negative error state to allow negative state values to be
> handled as expected.
>
> Fixes: f2989396553a ("acpi/nfit, libnvdimm: Introduce nvdimm_security_ops")
> Cc: Dave Jiang <[email protected]>
> Reported-by: Kees Cook <[email protected]>
> Tested-by: Kees Cook <[email protected]>
> Signed-off-by: Dan Williams <[email protected]>
Reviewed-by: Dave Jiang <[email protected]>
> ---
> include/linux/libnvdimm.h | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
> index 5440f11b0907..7315977b64da 100644
> --- a/include/linux/libnvdimm.h
> +++ b/include/linux/libnvdimm.h
> @@ -160,6 +160,7 @@ static inline struct nd_blk_region_desc
> *to_blk_region_desc(
> }
>
> enum nvdimm_security_state {
> + NVDIMM_SECURITY_ERROR = -1,
> NVDIMM_SECURITY_DISABLED,
> NVDIMM_SECURITY_UNLOCKED,
> NVDIMM_SECURITY_LOCKED,
>
