diff --git a/fs/ubifs/acl.c b/fs/ubifs/acl.c
new file mode 100644
index 0000000..5120712
--- /dev/null
+++ b/fs/ubifs/acl.c
@@ -0,0 +1,312 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+#include <linux/fs.h>
+#include <linux/xattr.h>
+#include <linux/posix_acl_xattr.h>
+
+#include "ubifs.h"
+
+#define UBIFS_ACL_VERSION	0x0001
+
+struct ubifs_acl_entry {
+	__le16 e_tag;
+	__le16 e_perm;
+	__le32 e_id;
+};
+
+struct ubifs_acl_entry_short {
+	__le16 e_tag;
+	__le16 e_perm;
+};
+
+struct ubifs_acl_header {
+	__le32 a_version;
+};
+
+#define UBIFS_ACL_HEADER_SZ		sizeof(struct ubifs_acl_header)
+#define UBIFS_ACL_ENTRY_SZ		sizeof(struct ubifs_acl_entry)
+#define UBIFS_ACL_ENTRY_SHORT_SZ	sizeof(struct ubifs_acl_entry_short)
+
+static inline size_t acl_size(int count)
+{
+	if (count <= 4) {
+		return UBIFS_ACL_HEADER_SZ +
+			count * UBIFS_ACL_ENTRY_SHORT_SZ;
+	} else {
+		return UBIFS_ACL_HEADER_SZ +
+			4 * UBIFS_ACL_ENTRY_SHORT_SZ +
+			(count - 4) * UBIFS_ACL_ENTRY_SZ;
+	}
+}
+
+static inline int acl_count(size_t size)
+{
+	ssize_t s;
+
+	size -= UBIFS_ACL_HEADER_SZ;
+	s = size - 4 * UBIFS_ACL_ENTRY_SHORT_SZ;
+	if (s < 0) {
+		if (size % UBIFS_ACL_ENTRY_SHORT_SZ)
+			return -1;
+		return size / UBIFS_ACL_ENTRY_SHORT_SZ;
+	} else {
+		if (s % UBIFS_ACL_ENTRY_SZ)
+			return -1;
+		return s / UBIFS_ACL_ENTRY_SZ + 4;
+	}
+}
+
+/* convert from in-memory ACL to on-flash ACL */
+static void *acl_to_flash(const struct posix_acl *acl, size_t *size, int type)
+{
+	struct ubifs_acl_header *hdr;
+	struct ubifs_acl_entry *uae;
+	int i;
+
+	*size = acl_size(acl->a_count);
+	hdr = kmalloc(*size, GFP_KERNEL);
+	if (!hdr)
+		return ERR_PTR(-ENOMEM);
+
+	hdr->a_version = cpu_to_le32(UBIFS_ACL_VERSION);
+	uae = (struct ubifs_acl_entry *) (hdr + 1);
+
+	for (i = 0; i < acl->a_count; i++) {
+		const struct posix_acl_entry *ae = &acl->a_entries[i];
+		uae->e_tag = cpu_to_le16(ae->e_tag);
+		uae->e_perm = cpu_to_le16(ae->e_perm);
+		switch (ae->e_tag) {
+		case ACL_USER_OBJ:
+		case ACL_GROUP_OBJ:
+		case ACL_MASK:
+		case ACL_OTHER:
+			/* for the 4 options, id is not used */
+			uae = (struct ubifs_acl_entry *) ((char *) uae +
+						UBIFS_ACL_ENTRY_SHORT_SZ);
+			break;
+		case ACL_USER:
+		{
+			uid_t u = from_kuid(&init_user_ns, ae->e_uid);
+			uae->e_id = cpu_to_le32(u);
+			uae = (struct ubifs_acl_entry *) ((char *) uae +
+						UBIFS_ACL_ENTRY_SZ);
+			break;
+		}
+		case ACL_GROUP:
+		{
+			gid_t g = from_kgid(&init_user_ns, ae->e_gid);
+			uae->e_id = cpu_to_le32(g);
+			uae = (struct ubifs_acl_entry *) ((char *) uae +
+						UBIFS_ACL_ENTRY_SZ);
+			break;
+		}
+		default:
+			goto fail;
+		}
+	}
+
+	return (void *) hdr;
+
+fail:
+	kfree(hdr);
+	return ERR_PTR(-EINVAL);
+}
+
+/* convert from on-flash ACL to in-memory ACL */
+static struct posix_acl *acl_from_flash(const void *value, size_t size)
+{
+	struct posix_acl *acl;
+	struct ubifs_acl_header *hdr = (struct ubifs_acl_header *) value;
+	struct ubifs_acl_entry *uae = (struct ubifs_acl_entry *) (hdr + 1);
+	const char *end = value + size;
+	int count, i;
+
+	if (!value)
+		return NULL;
+	if (size < UBIFS_ACL_HEADER_SZ)
+		return ERR_PTR(-EINVAL);
+	if (hdr->a_version != cpu_to_le32(UBIFS_ACL_VERSION))
+		return ERR_PTR(-EINVAL);
+
+	count = acl_count(size);
+	if (count < 0)
+		return ERR_PTR(-EINVAL);
+	if (count == 0)
+		return NULL;
+
+	acl = posix_acl_alloc(count, GFP_KERNEL);
+	if (!acl)
+		return ERR_PTR(-ENOMEM);
+
+	for (i = 0; i < count; i++) {
+		if ((char *) uae > end)
+			goto fail;
+
+		acl->a_entries[i].e_tag = le16_to_cpu(uae->e_tag);
+		acl->a_entries[i].e_perm = le16_to_cpu(uae->e_perm);
+		switch (acl->a_entries[i].e_tag) {
+		case ACL_USER_OBJ:
+		case ACL_GROUP_OBJ:
+		case ACL_MASK:
+		case ACL_OTHER:
+			/* for the 4 options, no id */
+			uae = (struct ubifs_acl_entry *) ((char *) uae +
+						UBIFS_ACL_ENTRY_SHORT_SZ);
+			break;
+		case ACL_USER:
+		{
+			uid_t u = le32_to_cpu(uae->e_id);
+			acl->a_entries[i].e_uid = make_kuid(&init_user_ns, u);
+			uae = (struct ubifs_acl_entry *) ((char *) uae +
+						UBIFS_ACL_ENTRY_SZ);
+			break;
+		}
+		case ACL_GROUP:
+		{
+			gid_t g = le32_to_cpu(uae->e_id);
+			acl->a_entries[i].e_gid = make_kgid(&init_user_ns, g);
+			uae = (struct ubifs_acl_entry *) ((char *) uae +
+						UBIFS_ACL_ENTRY_SZ);
+			break;
+		}
+		default:
+			goto fail;
+		}
+	}
+
+	if ((char *) uae != end)
+		goto fail;
+
+	return acl;
+
+fail:
+	posix_acl_release(acl);
+	return ERR_PTR(-EINVAL);
+}
+
+struct posix_acl *ubifs_get_acl(struct inode *inode, int type)
+{
+	struct posix_acl *acl;
+	char *name, *value = NULL;
+	int size = 0;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		name = XATTR_NAME_POSIX_ACL_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		name = XATTR_NAME_POSIX_ACL_DEFAULT;
+		break;
+	default:
+		BUG();
+	}
+
+	size = ubifs_do_getxattr(inode, name, NULL, 0);
+	if (size > 0) {
+		value = kmalloc(size, GFP_KERNEL);
+		if (!value)
+			return ERR_PTR(-ENOMEM);
+		size = ubifs_do_getxattr(inode, name, value, size);
+	}
+	if (size > 0)
+		acl = acl_from_flash(value, size);
+	else if (size == -ENODATA)
+		acl = NULL;
+	else if (size < 0)
+		return ERR_PTR(size);
+
+	kfree(value);
+	if (!IS_ERR(acl))
+		set_cached_acl(inode, type, acl);
+
+	return acl;
+}
+
+int ubifs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+{
+	char *name;
+	void *value = NULL;
+	size_t size = 0;
+	int err;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		name = XATTR_NAME_POSIX_ACL_ACCESS;
+		if (acl) {
+			err = posix_acl_equiv_mode(acl, &inode->i_mode);
+			if (err < 0)
+				return err;
+			if (err == 0)
+				acl = NULL;
+		}
+		break;
+
+	case ACL_TYPE_DEFAULT:
+		name = XATTR_NAME_POSIX_ACL_DEFAULT;
+		if (!S_ISDIR(inode->i_mode))
+			return acl ? -EACCES : 0;
+		break;
+
+	default:
+		BUG();
+	}
+
+	if (acl) {
+		value = acl_to_flash(acl, &size, type);
+		if (IS_ERR(value))
+			return (int) PTR_ERR(value);
+	}
+
+	err = ubifs_do_setxattr(inode, name, value, size, 0);
+	kfree(value);
+	if (!err)
+		set_cached_acl(inode, type, acl);
+	return err;
+}
+
+/*
+ * Initialize the ACLs of a new inode.
+ */
+int ubifs_init_acl(struct inode *dir, struct inode *inode)
+{
+	struct posix_acl *default_acl, *acl;
+	int err;
+
+	err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
+	if (err)
+		return err;
+
+	if (default_acl) {
+		mutex_lock(&inode->i_mutex);
+		err = ubifs_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
+		mutex_unlock(&inode->i_mutex);
+		posix_acl_release(default_acl);
+	}
+
+	if (acl) {
+		if (!err) {
+			mutex_lock(&inode->i_mutex);
+			err = ubifs_set_acl(inode, acl, ACL_TYPE_ACCESS);
+			mutex_unlock(&inode->i_mutex);
+		}
+		posix_acl_release(acl);
+	}
+
+	return err;
+}
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index 5c27c66..db5dd45 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -270,6 +270,10 @@ static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 		goto out_budg;
 	}
 
+	err = ubifs_init_acl(dir, inode);
+	if (err)
+		goto out_inode;
+
 	err = ubifs_init_security(dir, inode, &dentry->d_name);
 	if (err)
 		goto out_inode;
@@ -731,6 +735,10 @@ static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 		goto out_budg;
 	}
 
+	err = ubifs_init_acl(dir, inode);
+	if (err)
+		goto out_inode;
+
 	err = ubifs_init_security(dir, inode, &dentry->d_name);
 	if (err)
 		goto out_inode;
@@ -810,6 +818,10 @@ static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
 		goto out_budg;
 	}
 
+	err = ubifs_init_acl(dir, inode);
+	if (err)
+		goto out_inode;
+
 	init_special_inode(inode, inode->i_mode, rdev);
 	inode->i_size = ubifs_inode(inode)->ui_size = devlen;
 	ui = ubifs_inode(inode);
@@ -898,6 +910,10 @@ static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
 	ui->data_len = len;
 	inode->i_size = ubifs_inode(inode)->ui_size = len;
 
+	err = ubifs_init_acl(dir, inode);
+	if (err)
+		goto out_inode;
+
 	err = ubifs_init_security(dir, inode, &dentry->d_name);
 	if (err)
 		goto out_inode;
@@ -1188,6 +1204,10 @@ const struct inode_operations ubifs_dir_inode_operations = {
 	.getxattr    = ubifs_getxattr,
 	.listxattr   = ubifs_listxattr,
 	.removexattr = ubifs_removexattr,
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	.get_acl     = ubifs_get_acl,
+	.set_acl     = ubifs_set_acl,
+#endif
 };
 
 const struct file_operations ubifs_dir_operations = {
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index a3dfe2a..74f4c63 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -52,6 +52,7 @@
 #include "ubifs.h"
 #include <linux/mount.h>
 #include <linux/slab.h>
+#include <linux/posix_acl.h>
 
 static int read_block(struct inode *inode, void *addr, unsigned int block,
 		      struct ubifs_data_node *dn)
@@ -1246,6 +1247,11 @@ static int do_setattr(struct ubifs_info *c, struct inode *inode,
 		mark_inode_dirty_sync(inode);
 	mutex_unlock(&ui->ui_mutex);
 
+	if (attr->ia_valid & ATTR_MODE)
+		err = posix_acl_chmod(inode, inode->i_mode);
+	if (err)
+		return err;
+
 	if (release)
 		ubifs_release_budget(c, &req);
 	if (IS_SYNC(inode))
@@ -1557,6 +1563,10 @@ const struct inode_operations ubifs_file_inode_operations = {
 	.getxattr    = ubifs_getxattr,
 	.listxattr   = ubifs_listxattr,
 	.removexattr = ubifs_removexattr,
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	.get_acl     = ubifs_get_acl,
+	.set_acl     = ubifs_set_acl,
+#endif
 };
 
 const struct inode_operations ubifs_symlink_inode_operations = {
@@ -1568,6 +1578,10 @@ const struct inode_operations ubifs_symlink_inode_operations = {
 	.getxattr    = ubifs_getxattr,
 	.listxattr   = ubifs_listxattr,
 	.removexattr = ubifs_removexattr,
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	.get_acl     = ubifs_get_acl,
+	.set_acl     = ubifs_set_acl,
+#endif
 };
 
 const struct file_operations ubifs_file_operations = {
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 9547a278..52baad1 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -441,6 +441,9 @@ static int ubifs_show_options(struct seq_file *s, struct dentry *root)
 			   ubifs_compr_name(c->mount_opts.compr_type));
 	}
 
+	if (c->vfs_sb->s_flags & MS_POSIXACL)
+		seq_printf(s, ",acl");
+
 	return 0;
 }
 
@@ -926,6 +929,8 @@ enum {
 	Opt_chk_data_crc,
 	Opt_no_chk_data_crc,
 	Opt_override_compr,
+	Opt_acl,
+	Opt_noacl,
 	Opt_err,
 };
 
@@ -937,6 +942,8 @@ static const match_table_t tokens = {
 	{Opt_chk_data_crc, "chk_data_crc"},
 	{Opt_no_chk_data_crc, "no_chk_data_crc"},
 	{Opt_override_compr, "compr=%s"},
+	{Opt_acl, "acl"},
+	{Opt_noacl, "noacl"},
 	{Opt_err, NULL},
 };
 
@@ -1037,6 +1044,14 @@ static int ubifs_parse_options(struct ubifs_info *c, char *options,
 			c->default_compr = c->mount_opts.compr_type;
 			break;
 		}
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+		case Opt_acl:
+			c->vfs_sb->s_flags |= MS_POSIXACL;
+			break;
+		case Opt_noacl:
+			c->vfs_sb->s_flags &= ~MS_POSIXACL;
+			break;
+#endif
 		default:
 		{
 			unsigned long flag;
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 62aa1a5..b9ddc8d 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1767,6 +1767,20 @@ int ubifs_removexattr(struct dentry *dentry, const char *name);
 int ubifs_init_security(struct inode *dentry, struct inode *inode,
 			const struct qstr *qstr);
 
+/* acl.c */
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+int ubifs_init_acl(struct inode *dir, struct inode *inode);
+int ubifs_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+struct posix_acl *ubifs_get_acl(struct inode *inode, int type);
+#else
+static inline int ubifs_init_acl(struct inode *inode, struct inode *dir)
+{
+	return 0;
+}
+#define ubifs_get_acl NULL
+#define ubifs_set_acl NULL
+#endif
+
 /* super.c */
 struct inode *ubifs_iget(struct super_block *sb, unsigned long inum);
 
diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
index 6534b98..f2556d2 100644
--- a/fs/ubifs/xattr.c
+++ b/fs/ubifs/xattr.c
@@ -52,7 +52,6 @@
  * in the VFS inode cache. The xentries are cached in the LNC cache (see
  * tnc.c).
  *
- * ACL support is not implemented.
  */
 
 #include "ubifs.h"
@@ -78,6 +77,10 @@ enum {
 	USER_XATTR,
 	TRUSTED_XATTR,
 	SECURITY_XATTR,
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	POSIX_ACL_DEFAULT,
+	POSIX_ACL_ACCESS,
+#endif
 };
 
 static const struct inode_operations empty_iops;
@@ -276,6 +279,18 @@ static int check_namespace(const struct qstr *nm)
 		if (nm->name[sizeof(XATTR_SECURITY_PREFIX) - 1] == '\0')
 			return -EINVAL;
 		type = SECURITY_XATTR;
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	} else if (!strncmp(nm->name, XATTR_NAME_POSIX_ACL_DEFAULT,
+			    sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1)) {
+		if (nm->name[sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1] != '\0')
+			return -EINVAL;
+		type = POSIX_ACL_DEFAULT;
+	} else if (!strncmp(nm->name, XATTR_NAME_POSIX_ACL_ACCESS,
+			    sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1)) {
+		if (nm->name[sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1] != '\0')
+			return -EINVAL;
+		type = POSIX_ACL_ACCESS;
+#endif
 	} else
 		return -EOPNOTSUPP;
 
@@ -359,6 +374,9 @@ out_free:
 int ubifs_setxattr(struct dentry *dentry, const char *name,
 		   const void *value, size_t size, int flags)
 {
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	const struct xattr_handler *handler;
+#endif
 	struct qstr nm = QSTR_INIT(name, strlen(name));
 	int type;
 
@@ -369,6 +387,16 @@ int ubifs_setxattr(struct dentry *dentry, const char *name,
 	if (type < 0)
 		return type;
 
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	if (type == POSIX_ACL_DEFAULT || type == POSIX_ACL_ACCESS) {
+		if (type == POSIX_ACL_DEFAULT)
+			handler = &posix_acl_default_xattr_handler;
+		if (type == POSIX_ACL_ACCESS)
+			handler = &posix_acl_access_xattr_handler;
+		return handler->set(dentry, name, value, size, flags,
+				    handler->flags);
+	}
+#endif
 	return ubifs_do_setxattr(d_inode(dentry), name, value, size, flags);
 }
 
@@ -428,6 +456,9 @@ out_unlock:
 ssize_t ubifs_getxattr(struct dentry *dentry, const char *name,
 		       void *value, size_t size)
 {
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	const struct xattr_handler *handler;
+#endif
 	struct qstr nm = QSTR_INIT(name, strlen(name));
 	int type;
 
@@ -438,6 +469,16 @@ ssize_t ubifs_getxattr(struct dentry *dentry, const char *name,
 	if (type < 0)
 		return type;
 
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	if (type == POSIX_ACL_DEFAULT || type == POSIX_ACL_ACCESS) {
+		if (type == POSIX_ACL_DEFAULT)
+			handler = &posix_acl_default_xattr_handler;
+		if (type == POSIX_ACL_ACCESS)
+			handler = &posix_acl_access_xattr_handler;
+		return handler->get(dentry, name, value, size,
+				    handler->flags);
+	}
+#endif
 	return ubifs_do_getxattr(d_inode(dentry), name, value, size);
 }
 
@@ -547,20 +588,33 @@ out_cancel:
 
 int ubifs_removexattr(struct dentry *dentry, const char *name)
 {
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	const struct xattr_handler *handler;
+#endif
 	struct inode *inode, *host = d_inode(dentry);
 	struct ubifs_info *c = host->i_sb->s_fs_info;
 	struct qstr nm = QSTR_INIT(name, strlen(name));
 	struct ubifs_dent_node *xent;
 	union ubifs_key key;
-	int err;
+	int type, err;
 
 	dbg_gen("xattr '%s', ino %lu ('%pd')", name,
 		host->i_ino, dentry);
 	ubifs_assert(mutex_is_locked(&host->i_mutex));
 
-	err = check_namespace(&nm);
-	if (err < 0)
-		return err;
+	type = check_namespace(&nm);
+	if (type < 0)
+		return type;
+
+#ifdef CONFIG_UBIFS_FS_POSIX_ACL
+	if (type == POSIX_ACL_DEFAULT || type == POSIX_ACL_ACCESS) {
+		if (type == POSIX_ACL_DEFAULT)
+			handler = &posix_acl_default_xattr_handler;
+		if (type == POSIX_ACL_ACCESS)
+			handler = &posix_acl_access_xattr_handler;
+		return handler->set(dentry, name, NULL, 0, 0, handler->flags);
+	}
+#endif
 
 	xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
 	if (!xent)
