1 files changed, 36 insertions, 4 deletions

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index b441d82c338..138200bf5e0 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -700,7 +700,7 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size)
 	int r;
 	char *new_name = (char *) param + param->data_start;
 
-	if (new_name < (char *) (param + 1) ||
+	if (new_name < (char *) param->data ||
 	    invalid_str(new_name, (void *) param + param_size)) {
 		DMWARN("Invalid new logical volume name supplied.");
 		return -EINVAL;
@@ -726,7 +726,7 @@ static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
 	if (!md)
 		return -ENXIO;
 
-	if (geostr < (char *) (param + 1) ||
+	if (geostr < (char *) param->data ||
 	    invalid_str(geostr, (void *) param + param_size)) {
 		DMWARN("Invalid geometry supplied.");
 		goto out;
@@ -1233,7 +1233,7 @@ static int target_message(struct dm_ioctl *param, size_t param_size)
 	if (r)
 		goto out;
 
-	if (tmsg < (struct dm_target_msg *) (param + 1) ||
+	if (tmsg < (struct dm_target_msg *) param->data ||
 	    invalid_str(tmsg->message, (void *) param + param_size)) {
 		DMWARN("Invalid target message parameters.");
 		r = -EINVAL;
@@ -1358,7 +1358,7 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param)
 	if (tmp.data_size < sizeof(tmp))
 		return -EINVAL;
 
-	dmi = (struct dm_ioctl *) vmalloc(tmp.data_size);
+	dmi = vmalloc(tmp.data_size);
 	if (!dmi)
 		return -ENOMEM;
 
@@ -1515,3 +1515,35 @@ void dm_interface_exit(void)
 
 	dm_hash_exit();
 }
+
+/**
+ * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
+ * @md: Pointer to mapped_device
+ * @name: Buffer (size DM_NAME_LEN) for name
+ * @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
+ */
+int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
+{
+	int r = 0;
+	struct hash_cell *hc;
+
+	if (!md)
+		return -ENXIO;
+
+	dm_get(md);
+	down_read(&_hash_lock);
+	hc = dm_get_mdptr(md);
+	if (!hc || hc->md != md) {
+		r = -ENXIO;
+		goto out;
+	}
+
+	strcpy(name, hc->name);
+	strcpy(uuid, hc->uuid ? : "");
+
+out:
+	up_read(&_hash_lock);
+	dm_put(md);
+
+	return r;
+}