Merge branch 'fs.acl.rework' into for-next

110 files changed, 1828 insertions, 1117 deletions

diff --git a/Documentation/filesystems/locking.rst b/Documentation/filesystems/locking.rst
index 8f737e76935c..36fa2a83d714 100644
--- a/Documentation/filesystems/locking.rst
+++ b/Documentation/filesystems/locking.rst
@@ -70,7 +70,7 @@ prototypes::
 	const char *(*get_link) (struct dentry *, struct inode *, struct delayed_call *);
 	void (*truncate) (struct inode *);
 	int (*permission) (struct inode *, int, unsigned int);
-	struct posix_acl * (*get_acl)(struct inode *, int, bool);
+	struct posix_acl * (*get_inode_acl)(struct inode *, int, bool);
 	int (*setattr) (struct dentry *, struct iattr *);
 	int (*getattr) (const struct path *, struct kstat *, u32, unsigned int);
 	ssize_t (*listxattr) (struct dentry *, char *, size_t);
@@ -84,13 +84,14 @@ prototypes::
 	int (*fileattr_set)(struct user_namespace *mnt_userns,
 			    struct dentry *dentry, struct fileattr *fa);
 	int (*fileattr_get)(struct dentry *dentry, struct fileattr *fa);
+	struct posix_acl * (*get_acl)(struct user_namespace *, struct dentry *, int);
 
 locking rules:
 	all may block
 
-=============	=============================================
+==============	=============================================
 ops		i_rwsem(inode)
-=============	=============================================
+==============	=============================================
 lookup:		shared
 create:		exclusive
 link:		exclusive (both)
@@ -104,6 +105,7 @@ readlink:	no
 get_link:	no
 setattr:	exclusive
 permission:	no (may not block if called in rcu-walk mode)
+get_inode_acl:	no
 get_acl:	no
 getattr:	no
 listxattr:	no
@@ -113,7 +115,7 @@ atomic_open:	shared (exclusive if O_CREAT is set in open flags)
 tmpfile:	no
 fileattr_get:	no or exclusive
 fileattr_set:	exclusive
-=============	=============================================
+==============	=============================================
 
 
 	Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_rwsem
diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesystems/porting.rst
index df0dc37e6f58..d2d684ae7798 100644
--- a/Documentation/filesystems/porting.rst
+++ b/Documentation/filesystems/porting.rst
@@ -462,8 +462,8 @@ ERR_PTR(...).
 argument; instead of passing IPERM_FLAG_RCU we add MAY_NOT_BLOCK into mask.
 
 generic_permission() has also lost the check_acl argument; ACL checking
-has been taken to VFS and filesystems need to provide a non-NULL ->i_op->get_acl
-to read an ACL from disk.
+has been taken to VFS and filesystems need to provide a non-NULL
+->i_op->get_inode_acl to read an ACL from disk.
 
 ---
 
diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst
index 2b55f71e2ae1..2c15e7053113 100644
--- a/Documentation/filesystems/vfs.rst
+++ b/Documentation/filesystems/vfs.rst
@@ -435,7 +435,7 @@ As of kernel 2.6.22, the following members are defined:
 		const char *(*get_link) (struct dentry *, struct inode *,
 					 struct delayed_call *);
 		int (*permission) (struct user_namespace *, struct inode *, int);
-		struct posix_acl * (*get_acl)(struct inode *, int, bool);
+		struct posix_acl * (*get_inode_acl)(struct inode *, int, bool);
 		int (*setattr) (struct user_namespace *, struct dentry *, struct iattr *);
 		int (*getattr) (struct user_namespace *, const struct path *, struct kstat *, u32, unsigned int);
 		ssize_t (*listxattr) (struct dentry *, char *, size_t);
@@ -443,7 +443,8 @@ As of kernel 2.6.22, the following members are defined:
 		int (*atomic_open)(struct inode *, struct dentry *, struct file *,
 				   unsigned open_flag, umode_t create_mode);
 		int (*tmpfile) (struct user_namespace *, struct inode *, struct file *, umode_t);
-	        int (*set_acl)(struct user_namespace *, struct inode *, struct posix_acl *, int);
+		struct posix_acl * (*get_acl)(struct user_namespace *, struct dentry *, int);
+	        int (*set_acl)(struct user_namespace *, struct dentry *, struct posix_acl *, int);
 		int (*fileattr_set)(struct user_namespace *mnt_userns,
 				    struct dentry *dentry, struct fileattr *fa);
 		int (*fileattr_get)(struct dentry *dentry, struct fileattr *fa);
diff --git a/fs/9p/acl.c b/fs/9p/acl.c
index 4dac4a0dc5f4..c397c51f80d9 100644
--- a/fs/9p/acl.c
+++ b/fs/9p/acl.c
@@ -17,34 +17,64 @@
 #include "v9fs_vfs.h"
 #include "fid.h"
 
-static struct posix_acl *__v9fs_get_acl(struct p9_fid *fid, char *name)
+static struct posix_acl *v9fs_fid_get_acl(struct p9_fid *fid, const char *name)
 {
 	ssize_t size;
 	void *value = NULL;
 	struct posix_acl *acl = NULL;
 
 	size = v9fs_fid_xattr_get(fid, name, NULL, 0);
-	if (size > 0) {
-		value = kzalloc(size, GFP_NOFS);
-		if (!value)
-			return ERR_PTR(-ENOMEM);
-		size = v9fs_fid_xattr_get(fid, name, value, size);
-		if (size > 0) {
-			acl = posix_acl_from_xattr(&init_user_ns, value, size);
-			if (IS_ERR(acl))
-				goto err_out;
-		}
-	} else if (size == -ENODATA || size == 0 ||
-		   size == -ENOSYS || size == -EOPNOTSUPP) {
-		acl = NULL;
-	} else
-		acl = ERR_PTR(-EIO);
-
-err_out:
+	if (size < 0)
+		return ERR_PTR(size);
+	if (size == 0)
+		return ERR_PTR(-ENODATA);
+
+	value = kzalloc(size, GFP_NOFS);
+	if (!value)
+		return ERR_PTR(-ENOMEM);
+
+	size = v9fs_fid_xattr_get(fid, name, value, size);
+	if (size < 0)
+		acl = ERR_PTR(size);
+	else if (size == 0)
+		acl = ERR_PTR(-ENODATA);
+	else
+		acl = posix_acl_from_xattr(&init_user_ns, value, size);
 	kfree(value);
 	return acl;
 }
 
+static struct posix_acl *v9fs_acl_get(struct dentry *dentry, const char *name)
+{
+	struct p9_fid *fid;
+	struct posix_acl *acl = NULL;
+
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return ERR_CAST(fid);
+
+	acl = v9fs_fid_get_acl(fid, name);
+	p9_fid_put(fid);
+	return acl;
+}
+
+static struct posix_acl *__v9fs_get_acl(struct p9_fid *fid, const char *name)
+{
+	int retval;
+	struct posix_acl *acl = NULL;
+
+	acl = v9fs_fid_get_acl(fid, name);
+	if (!IS_ERR(acl))
+		return acl;
+
+	retval = PTR_ERR(acl);
+	if (retval == -ENODATA || retval == -ENOSYS || retval == -EOPNOTSUPP)
+		return NULL;
+
+	/* map everything else to -EIO */
+	return ERR_PTR(-EIO);
+}
+
 int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
 {
 	int retval = 0;
@@ -89,7 +119,7 @@ static struct posix_acl *v9fs_get_cached_acl(struct inode *inode, int type)
 	return acl;
 }
 
-struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type, bool rcu)
+struct posix_acl *v9fs_iop_get_inode_acl(struct inode *inode, int type, bool rcu)
 {
 	struct v9fs_session_info *v9ses;
 
@@ -109,6 +139,112 @@ struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type, bool rcu)
 
 }
 
+struct posix_acl *v9fs_iop_get_acl(struct user_namespace *mnt_userns,
+				   struct dentry *dentry, int type)
+{
+	struct v9fs_session_info *v9ses;
+
+	v9ses = v9fs_dentry2v9ses(dentry);
+	/* We allow set/get/list of acl when access=client is not specified. */
+	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
+		return v9fs_acl_get(dentry, posix_acl_xattr_name(type));
+	return v9fs_get_cached_acl(d_inode(dentry), type);
+}
+
+int v9fs_iop_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry,
+		     struct posix_acl *acl, int type)
+{
+	int retval;
+	size_t size = 0;
+	void *value = NULL;
+	const char *acl_name;
+	struct v9fs_session_info *v9ses;
+	struct inode *inode = d_inode(dentry);
+
+	if (acl) {
+		retval = posix_acl_valid(inode->i_sb->s_user_ns, acl);
+		if (retval)
+			goto err_out;
+
+		size = posix_acl_xattr_size(acl->a_count);
+
+		value = kzalloc(size, GFP_NOFS);
+		if (!value) {
+			retval = -ENOMEM;
+			goto err_out;
+		}
+
+		retval = posix_acl_to_xattr(&init_user_ns, acl, value, size);
+		if (retval < 0)
+			goto err_out;
+	}
+
+	/*
+	 * set the attribute on the remote. Without even looking at the
+	 * xattr value. We leave it to the server to validate
+	 */
+	acl_name = posix_acl_xattr_name(type);
+	v9ses = v9fs_dentry2v9ses(dentry);
+	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) {
+		retval = v9fs_xattr_set(dentry, acl_name, value, size, 0);
+		goto err_out;
+	}
+
+	if (S_ISLNK(inode->i_mode)) {
+		retval = -EOPNOTSUPP;
+		goto err_out;
+	}
+
+	if (!inode_owner_or_capable(&init_user_ns, inode)) {
+		retval = -EPERM;
+		goto err_out