userns: Convert EVM to deal with kuids and kgids in it's hmac computation

Cc: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

init/Kconfig

@@ -926,7 +926,6 @@ config UIDGID_CONVERTED
 	# List of kernel pieces that need user namespace work
 	# Features
 	depends on IMA = n
-	depends on EVM = n
 
 	# Networking
 	depends on NET_9P = n

security/integrity/evm/evm_crypto.c

@@ -106,8 +106,8 @@ static void hmac_add_misc(struct shash_desc *desc, struct inode *inode,
 	memset(&hmac_misc, 0, sizeof hmac_misc);
 	hmac_misc.ino = inode->i_ino;
 	hmac_misc.generation = inode->i_generation;
-	hmac_misc.uid = inode->i_uid;
-	hmac_misc.gid = inode->i_gid;
+	hmac_misc.uid = from_kuid(&init_user_ns, inode->i_uid);
+	hmac_misc.gid = from_kgid(&init_user_ns, inode->i_gid);
 	hmac_misc.mode = inode->i_mode;
 	crypto_shash_update(desc, (const u8 *)&hmac_misc, sizeof hmac_misc);
 	crypto_shash_final(desc, digest);