userns: Convert loop to use kuid_t instead of uid_t

Cc: Jens Axboe <jaxboe@fusionio.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

drivers/block/loop.c

@@ -1038,10 +1038,10 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info)
 {
 	int err;
 	struct loop_func_table *xfer;
-	uid_t uid = current_uid();
+	kuid_t uid = current_uid();
 
 	if (lo->lo_encrypt_key_size &&
-	    lo->lo_key_owner != uid &&
+	    !uid_eq(lo->lo_key_owner, uid) &&
 	    !capable(CAP_SYS_ADMIN))
 		return -EPERM;
 	if (lo->lo_state != Lo_bound)

include/linux/loop.h

@@ -44,7 +44,7 @@ struct loop_device {
 	int		lo_encrypt_key_size;
 	struct loop_func_table *lo_encryption;
 	__u32           lo_init[2];
-	uid_t		lo_key_owner;	/* Who set the key */
+	kuid_t		lo_key_owner;	/* Who set the key */
 	int		(*ioctl)(struct loop_device *, int cmd, 
 				 unsigned long arg); 
 

init/Kconfig

@@ -960,7 +960,6 @@ config UIDGID_CONVERTED
 	depends on !UML || HOSTFS = n
 
 	# The rare drivers that won't build
-	depends on BLK_DEV_LOOP = n
 	depends on ANDROID_BINDER_IPC = n
 
 	# Security modules