1 files changed, 54 insertions, 4 deletions

diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c
index 647a99dd3182..df7f070e96fb 100644
--- a/drivers/nvdimm/security.c
+++ b/drivers/nvdimm/security.c
@@ -15,6 +15,9 @@
 #include "nd-core.h"
 #include "nd.h"
 
+#define NVDIMM_BASE_KEY         0
+#define NVDIMM_NEW_KEY          1
+
 static bool key_revalidate = true;
 module_param(key_revalidate, bool, 0444);
 MODULE_PARM_DESC(key_revalidate, "Require key validation at init.");
@@ -70,7 +73,7 @@ static struct key *nvdimm_request_key(struct nvdimm *nvdimm)
 }
 
 static struct key *nvdimm_lookup_user_key(struct nvdimm *nvdimm,
-                key_serial_t id)
+                key_serial_t id, int subclass)
 {
         key_ref_t keyref;
         struct key *key;
@@ -86,10 +89,10 @@ static struct key *nvdimm_lookup_user_key(struct nvdimm *nvdimm,
                 key_put(key);
                 return NULL;
         }
-        dev_dbg(dev, "%s: key found: %#x\n", __func__, key_serial(key));
 
+        dev_dbg(dev, "%s: key found: %#x\n", __func__, key_serial(key));
 
-        down_read(&key->sem);
+        down_read_nested(&key->sem, subclass);
         epayload = dereference_key_locked(key);
         if (epayload->decrypted_datalen != NVDIMM_PASSPHRASE_LEN) {
                 up_read(&key->sem);
@@ -197,7 +200,7 @@ int nvdimm_security_disable(struct nvdimm *nvdimm, unsigned int keyid)
                 return -EIO;
         }
 
-        key = nvdimm_lookup_user_key(nvdimm, keyid);
+        key = nvdimm_lookup_user_key(nvdimm, keyid, NVDIMM_BASE_KEY);
         if (!key)
                 return -ENOKEY;
 
@@ -209,3 +212,50 @@ int nvdimm_security_disable(struct nvdimm *nvdimm, unsigned int keyid)
         nvdimm->sec.state = nvdimm_security_state(nvdimm);
         return rc;
 }
+
+int nvdimm_security_update(struct nvdimm *nvdimm, unsigned int keyid,
+                unsigned int new_keyid)
+{
+        struct device *dev = &nvdimm->dev;
+        struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+        struct key *key, *newkey;
+        int rc;
+
+        /* The bus lock should be held at the top level of the call stack */
+        lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
+
+        if (!nvdimm->sec.ops || !nvdimm->sec.ops->change_key
+                        || nvdimm->sec.state < 0)
+                return -EOPNOTSUPP;
+
+        if (nvdimm->sec.state >= NVDIMM_SECURITY_FROZEN) {
+                dev_warn(dev, "Incorrect security state: %d\n",
+                                nvdimm->sec.state);
+                return -EIO;
+        }
+
+        if (keyid == 0)
+                key = NULL;
+        else {
+                key = nvdimm_lookup_user_key(nvdimm, keyid, NVDIMM_BASE_KEY);
+                if (!key)
+                        return -ENOKEY;
+        }
+
+        newkey = nvdimm_lookup_user_key(nvdimm, new_keyid, NVDIMM_NEW_KEY);
+        if (!newkey) {
+                nvdimm_put_key(key);
+                return -ENOKEY;
+        }
+
+        rc = nvdimm->sec.ops->change_key(nvdimm, key ? key_data(key) : NULL,
+                        key_data(newkey));
+        dev_dbg(dev, "key: %d %d update: %s\n",
+                        key_serial(key), key_serial(newkey),
+                        rc == 0 ? "success" : "fail");
+
+        nvdimm_put_key(newkey);
+        nvdimm_put_key(key);
+        nvdimm->sec.state = nvdimm_security_state(nvdimm);
+        return rc;
+}