diff --git a/Documentation/ABI/testing/evm b/Documentation/ABI/testing/evm
index d12cb2eae9ee..bfe529eb26b2 100644
--- a/Documentation/ABI/testing/evm
+++ b/Documentation/ABI/testing/evm
@@ -57,3 +57,16 @@ Description:
 		dracut (via 97masterkey and 98integrity) and systemd (via
 		core/ima-setup) have support for loading keys at boot
 		time.
+
+What:		security/evm_xattrs
+Date:		April 2018
+Contact:	Matthew Garrett <mjg59@google.com>
+Description:
+		Shows the set of extended attributes used to calculate or
+		validate the EVM signature, and allows additional attributes
+		to be added at runtime. Adding additional extended attributes
+		will result in any existing signatures generated without the
+		additional attributes becoming invalid, and any signatures
+		generated after additional attributes are added will only be
+		valid if the same additional attributes are configured on
+		system boot.
diff --git a/security/integrity/evm/evm.h b/security/integrity/evm/evm.h
index 45c4a89c02ff..1257c3c24723 100644
--- a/security/integrity/evm/evm.h
+++ b/security/integrity/evm/evm.h
@@ -30,6 +30,11 @@
 #define EVM_INIT_MASK (EVM_INIT_HMAC | EVM_INIT_X509 | EVM_SETUP_COMPLETE | \
 		       EVM_ALLOW_METADATA_WRITES)
 
+struct xattr_list {
+	struct list_head list;
+	char *name;
+};
+
 extern int evm_initialized;
 
 #define EVM_ATTR_FSUUID		0x0001
@@ -40,7 +45,7 @@ extern struct crypto_shash *hmac_tfm;
 extern struct crypto_shash *hash_tfm;
 
 /* List of EVM protected security xattrs */
-extern char *evm_config_xattrnames[];
+extern struct list_head evm_config_xattrnames;
 
 int evm_init_key(void);
 int evm_update_evmxattr(struct dentry *dentry,
diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
index a46fba322340..caeea20670cc 100644
--- a/security/integrity/evm/evm_crypto.c
+++ b/security/integrity/evm/evm_crypto.c
@@ -192,8 +192,8 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry,
 				char type, char *digest)
 {
 	struct inode *inode = d_backing_inode(dentry);
+	struct xattr_list *xattr;
 	struct shash_desc *desc;
-	char **xattrname;
 	size_t xattr_size = 0;
 	char *xattr_value = NULL;
 	int error;
@@ -208,14 +208,14 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry,
 		return PTR_ERR(desc);
 
 	error = -ENODATA;
-	for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++) {
+	list_for_each_entry(xattr, &evm_config_xattrnames, list) {
 		bool is_ima = false;
 
-		if (strcmp(*xattrname, XATTR_NAME_IMA) == 0)
+		if (strcmp(xattr->name, XATTR_NAME_IMA) == 0)
 			is_ima = true;
 
 		if ((req_xattr_name && req_xattr_value)
-		    && !strcmp(*xattrname, req_xattr_name)) {
+		    && !strcmp(xattr->name, req_xattr_name)) {
 			error = 0;
 			crypto_shash_update(desc, (const u8 *)req_xattr_value,
 					     req_xattr_value_len);
@@ -223,7 +223,7 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry,
 				ima_present = true;
 			continue;
 		}
-		size = vfs_getxattr_alloc(dentry, *xattrname,
+		size = vfs_getxattr_alloc(dentry, xattr->name,
 					  &xattr_value, xattr_size, GFP_NOFS);
 		if (size == -ENOMEM) {
 			error = -ENOMEM;
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 9ea9c19a545c..86b1632d6b5b 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -35,7 +35,7 @@ static const char * const integrity_status_msg[] = {
 };
 int evm_hmac_attrs;
 
-char *evm_config_xattrnames[] = {
+char *evm_config_default_xattrnames[] = {
 #ifdef CONFIG_SECURITY_SELINUX
 	XATTR_NAME_SELINUX,
 #endif
@@ -57,6 +57,8 @@ char *evm_config_xattrnames[] = {
 	NULL
 };
 
+LIST_HEAD(evm_config_xattrnames);
+
 static int evm_fixmode;
 static int __init evm_set_fixmode(char *str)
 {
@@ -66,12 +68,30 @@ static int __init evm_set_fixmode(char *str)
 }
 __setup("evm=", evm_set_fixmode);
 
-static void __init evm_init_config(void)
+static int __init evm_init_config(void)
 {
+	struct xattr_list *tmp;
+	char **xattrname;
+
+	for (xattrname = evm_config_default_xattrnames; *xattrname != NULL;
+	     xattrname++) {
+		tmp = kmalloc(sizeof(struct xattr_list), GFP_KERNEL);
+		if (!tmp)
+			return -ENOMEM;
+		tmp->name = kstrdup(*xattrname, GFP_KERNEL);
+		if (!tmp->name) {
+			kfree(tmp);
+			return -ENOMEM;
+		}
+		list_add_tail(&tmp->list, &evm_config_xattrnames);
+	}
+
 #ifdef CONFIG_EVM_ATTR_FSUUID
 	evm_hmac_attrs |= EVM_ATTR_FSUUID;
 #endif
 	pr_info("HMAC attrs: 0x%x\n", evm_hmac_attrs);
+
+	return 0;
 }
 
 static bool evm_key_loaded(void)
@@ -82,15 +102,15 @@ static bool evm_key_loaded(void)
 static int evm_find_protected_xattrs(struct dentry *dentry)
 {
 	struct inode *inode = d_backing_inode(dentry);
-	char **xattr;
+	struct xattr_list *xattr;
 	int error;
 	int count = 0;
 
 	if (!(inode->i_opflags & IOP_XATTR))
 		return -EOPNOTSUPP;
 
-	for (xattr = evm_config_xattrnames; *xattr != NULL; xattr++) {
-		error = __vfs_getxattr(dentry, inode, *xattr, NULL, 0);
+	list_for_each_entry(xattr, &evm_config_xattrnames, list) {
+		error = __vfs_getxattr(dentry, inode, xattr->name, NULL, 0);
 		if (error < 0) {
 			if (error == -ENODATA)
 				continue;
@@ -211,24 +231,25 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry,
 
 static int evm_protected_xattr(const char *req_xattr_name)
 {
-	char **xattrname;
 	int namelen;
 	int found = 0;
+	struct xattr_list *xattr;
 
 	namelen = strlen(req_xattr_name);
-	for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++) {
-		if ((strlen(*xattrname) == namelen)
-		    && (strncmp(req_xattr_name, *xattrname, namelen) == 0)) {
+	list_for_each_entry(xattr, &evm_config_xattrnames, list) {
+		if ((strlen(xattr->name) == namelen)
+		    && (strncmp(req_xattr_name, xattr->name, namelen) == 0)) {
 			found = 1;
 			break;
 		}
 		if (strncmp(req_xattr_name,
-			    *xattrname + XATTR_SECURITY_PREFIX_LEN,
+			    xattr->name + XATTR_SECURITY_PREFIX_LEN,
 			    strlen(req_xattr_name)) == 0) {
 			found = 1;
 			break;
 		}
 	}
+
 	return found;
 }
 
@@ -544,20 +565,37 @@ void __init evm_load_x509(void)
 static int __init init_evm(void)
 {
 	int error;
+	struct list_head *pos, *q;
+	struct xattr_list *xattr;
 
-	evm_init_config();
+	error = evm_init_config();
+	if (error)
+		goto error;
 
 	error = integrity_init_keyring(INTEGRITY_KEYRING_EVM);
 	if (error)
-		return error;
+		goto error;
 
 	error = evm_init_secfs();
 	if (error < 0) {
 		pr_info("Error registering secfs\n");
-		return error;
+		goto error;
 	}
 
-	return 0;
+error:
+	if (error != 0) {
+		if (!list_empty(&evm_config_xattrnames)) {
+			list_for_each_safe(pos, q, &evm_config_xattrnames) {
+				xattr = list_entry(pos, struct xattr_list,
+						   list);
+				list_del(pos);
+				kfree(xattr->name);
+				kfree(xattr);
+			}
+		}
+	}
+
+	return error;
 }
 
 /*
@@ -565,10 +603,11 @@ static int __init init_evm(void)
  */
 static int __init evm_display_config(void)
 {
-	char **xattrname;
+	struct xattr_list *xattr;
+
+	list_for_each_entry(xattr, &evm_config_xattrnames, list)
+		pr_info("%s\n", xattr->name);
 
-	for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++)
-		pr_info("%s\n", *xattrname);
 	return 0;
 }
 
diff --git a/security/integrity/evm/evm_secfs.c b/security/integrity/evm/evm_secfs.c
index feba03bbedae..3b371125d439 100644
--- a/security/integrity/evm/evm_secfs.c
+++ b/security/integrity/evm/evm_secfs.c
@@ -20,6 +20,7 @@
 #include "evm.h"
 
 static struct dentry *evm_init_tpm;
+static struct dentry *evm_xattrs;
 
 /**
  * evm_read_key - read() for <securityfs>/evm
@@ -107,13 +108,102 @@ static const struct file_operations evm_key_ops = {
 	.write		= evm_write_key,
 };
 
-int __init evm_init_secfs(void)
+/**
+ * evm_read_xattrs - read() for <securityfs>/evm_xattrs
+ *
+ * @filp: file pointer, not actually used
+ * @buf: where to put the result
+ * @count: maximum to send along
+ * @ppos: where to start
+ *
+ * Returns number of bytes read or error code, as appropriate
+ */
+static ssize_t evm_read_xattrs(struct file *filp, char __user *buf,
+			       size_t count, loff_t *ppos)
 {
-	int error = 0;
+	char *temp;
+	int offset = 0;
+	ssize_t rc, size = 0;
+	struct xattr_list *xattr;
+
+	if (*ppos != 0)
+		return 0;
 
-	evm_init_tpm = securityfs_create_file("evm", S_IRUSR | S_IRGRP,
-					      NULL, NULL, &evm_key_ops);
+	list_for_each_entry(xattr, &evm_config_xattrnames, list)
+		size += strlen(xattr->name) + 1;
+
+	temp = kmalloc(size + 1, GFP_KERNEL);
+	if (!temp)
+		return -ENOMEM;
+
+	list_for_each_entry(xattr, &evm_config_xattrnames, list) {
+		sprintf(temp + offset, "%s\n", xattr->name);
+		offset += strlen(xattr->name) + 1;
+	}
+
+	rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
+
+	return rc;
+}
+
+/**
+ * evm_write_xattrs - write() for <securityfs>/evm_xattrs
+ * @file: file pointer, not actually used
+ * @buf: where to get the data from
+ * @count: bytes sent
+ * @ppos: where to start
+ *
+ * Returns number of bytes written or error code, as appropriate
+ */
+static ssize_t evm_write_xattrs(struct file *file, const char __user *buf,
+				size_t count, loff_t *ppos)
+{
+	int len;
+	struct xattr_list *xattr;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (*ppos != 0)
+		return -EINVAL;
+
+	xattr = kmalloc(sizeof(struct xattr_list), GFP_KERNEL);
+	if (!xattr)
+		return -ENOMEM;
+
+	xattr->name = memdup_user_nul(buf, count);
+	if (!xattr->name) {
+		kfree(xattr);
+		return -ENOMEM;
+	}
+
+	/* Remove any trailing newline */
+	len = strlen(xattr->name);
+	if (xattr->name[len-1] == '\n')
+		xattr->name[len-1] = '\0';
+
+	list_add_tail(&xattr->list, &evm_config_xattrnames);
+	return count;
+}
+
+static const struct file_operations evm_xattr_ops = {
+	.read		= evm_read_xattrs,
+	.write		= evm_write_xattrs,
+};
+
+int __init evm_init_secfs(void)
+{
+	evm_init_tpm = securityfs_create_file("evm", 0440, NULL, NULL,
+					      &evm_key_ops);
 	if (!evm_init_tpm || IS_ERR(evm_init_tpm))
-		error = -EFAULT;
-	return error;
+		return -EFAULT;
+
+	evm_xattrs = securityfs_create_file("evm_xattrs", 0440, NULL, NULL,
+					    &evm_xattr_ops);
+	if (!evm_xattrs || IS_ERR(evm_xattrs)) {
+		securityfs_remove(evm_init_tpm);
+		return -EFAULT;
+	}
+
+	return 0;
 }
