libnvdimm: Validate command family indices

The ND_CMD_CALL format allows for a general passthrough of passlisted
commands targeting a given command set. However there is no validation
of the family index relative to what the bus supports.

- Update the NFIT bus implementation (the only one that supports
  ND_CMD_CALL passthrough) to also passlist the valid set of command
  family indices.

- Update the generic __nd_ioctl() path to validate that field on behalf
  of all implementations.

Fixes: 31eca76ba2 ("nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism")
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>

drivers/acpi/nfit/core.c

@@ -1823,6 +1823,7 @@ static void populate_shutdown_status(struct nfit_mem *nfit_mem)
 static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
 		struct nfit_mem *nfit_mem, u32 device_handle)
 {
+	struct nvdimm_bus_descriptor *nd_desc = &acpi_desc->nd_desc;
 	struct acpi_device *adev, *adev_dimm;
 	struct device *dev = acpi_desc->dev;
 	unsigned long dsm_mask, label_mask;
@@ -1834,6 +1835,7 @@ static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
 	/* nfit test assumes 1:1 relationship between commands and dsms */
 	nfit_mem->dsm_mask = acpi_desc->dimm_cmd_force_en;
 	nfit_mem->family = NVDIMM_FAMILY_INTEL;
+	set_bit(NVDIMM_FAMILY_INTEL, &nd_desc->dimm_family_mask);
 
 	if (dcr->valid_fields & ACPI_NFIT_CONTROL_MFG_INFO_VALID)
 		sprintf(nfit_mem->id, "%04x-%02x-%04x-%08x",
@@ -1886,10 +1888,13 @@ static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
 	 * Note, that checking for function0 (bit0) tells us if any commands
 	 * are reachable through this GUID.
 	 */
+	clear_bit(NVDIMM_FAMILY_INTEL, &nd_desc->dimm_family_mask);
 	for (i = 0; i <= NVDIMM_FAMILY_MAX; i++)
-		if (acpi_check_dsm(adev_dimm->handle, to_nfit_uuid(i), 1, 1))
+		if (acpi_check_dsm(adev_dimm->handle, to_nfit_uuid(i), 1, 1)) {
+			set_bit(i, &nd_desc->dimm_family_mask);
 			if (family < 0 || i == default_dsm_family)
 				family = i;
+		}
 
 	/* limit the supported commands to those that are publicly documented */
 	nfit_mem->family = family;
@@ -2153,6 +2158,9 @@ static void acpi_nfit_init_dsms(struct acpi_nfit_desc *acpi_desc)
 
 	nd_desc->cmd_mask = acpi_desc->bus_cmd_force_en;
 	nd_desc->bus_dsm_mask = acpi_desc->bus_nfit_cmd_force_en;
+	set_bit(ND_CMD_CALL, &nd_desc->cmd_mask);
+	set_bit(NVDIMM_BUS_FAMILY_NFIT, &nd_desc->bus_family_mask);
+
 	adev = to_acpi_dev(acpi_desc);
 	if (!adev)
 		return;
@@ -2160,7 +2168,6 @@ static void acpi_nfit_init_dsms(struct acpi_nfit_desc *acpi_desc)
 	for (i = ND_CMD_ARS_CAP; i <= ND_CMD_CLEAR_ERROR; i++)
 		if (acpi_check_dsm(adev->handle, guid, 1, 1ULL << i))
 			set_bit(i, &nd_desc->cmd_mask);
-	set_bit(ND_CMD_CALL, &nd_desc->cmd_mask);
 
 	dsm_mask =
 		(1 << ND_CMD_ARS_CAP) |

drivers/acpi/nfit/nfit.h

@@ -33,7 +33,6 @@
 		| ACPI_NFIT_MEM_RESTORE_FAILED | ACPI_NFIT_MEM_FLUSH_FAILED \
 		| ACPI_NFIT_MEM_NOT_ARMED | ACPI_NFIT_MEM_MAP_FAILED)
 
-#define NVDIMM_FAMILY_MAX NVDIMM_FAMILY_HYPERV
 #define NVDIMM_CMD_MAX 31
 
 #define NVDIMM_STANDARD_CMDMASK \

drivers/nvdimm/bus.c

@@ -1037,9 +1037,25 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
 		dimm_name = "bus";
 	}
 
+	/* Validate command family support against bus declared support */
 	if (cmd == ND_CMD_CALL) {
+		unsigned long *mask;
+
 		if (copy_from_user(&pkg, p, sizeof(pkg)))
 			return -EFAULT;
+
+		if (nvdimm) {
+			if (pkg.nd_family > NVDIMM_FAMILY_MAX)
+				return -EINVAL;
+			mask = &nd_desc->dimm_family_mask;
+		} else {
+			if (pkg.nd_family > NVDIMM_BUS_FAMILY_MAX)
+				return -EINVAL;
+			mask = &nd_desc->bus_family_mask;
+		}
+
+		if (!test_bit(pkg.nd_family, mask))
+			return -EINVAL;
 	}
 
 	if (!desc ||

include/linux/libnvdimm.h

@@ -78,6 +78,8 @@ struct nvdimm_bus_descriptor {
 	const struct attribute_group **attr_groups;
 	unsigned long bus_dsm_mask;
 	unsigned long cmd_mask;
+	unsigned long dimm_family_mask;
+	unsigned long bus_family_mask;
 	struct module *module;
 	char *provider_name;
 	struct device_node *of_node;

include/uapi/linux/ndctl.h

@@ -245,6 +245,10 @@ struct nd_cmd_pkg {
 #define NVDIMM_FAMILY_MSFT 3
 #define NVDIMM_FAMILY_HYPERV 4
 #define NVDIMM_FAMILY_PAPR 5
+#define NVDIMM_FAMILY_MAX NVDIMM_FAMILY_PAPR
+
+#define NVDIMM_BUS_FAMILY_NFIT 0
+#define NVDIMM_BUS_FAMILY_MAX NVDIMM_BUS_FAMILY_NFIT
 
 #define ND_IOCTL_CALL			_IOWR(ND_IOCTL, ND_CMD_CALL,\
 					struct nd_cmd_pkg)