Unverified Commit 03fd1402 authored by Christian Brauner's avatar Christian Brauner Committed by Christian Brauner (Microsoft)
Browse files

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

parents b4dd412d 0a26bde2

Documentation/filesystems/locking.rst

+6 −4
Original line number Diff line number Diff line
@@ -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

Documentation/filesystems/porting.rst

+2 −2
Original line number Diff line number Diff line
@@ -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.



---

Documentation/filesystems/vfs.rst

+3 −2
Original line number Diff line number Diff line
@@ -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);

fs/9p/acl.c

+155 −140
Original line number Diff line number Diff line
@@ -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) {

	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) {

	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);

			if (IS_ERR(acl))

				goto err_out;

	kfree(value);

	return acl;

}

	} else if (size == -ENODATA || size == 0 ||

		   size == -ENOSYS || size == -EOPNOTSUPP) {

		acl = NULL;

	} else

		acl = ERR_PTR(-EIO);



err_out:

	kfree(value);

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;

	}



	switch (type) {

	case ACL_TYPE_ACCESS:

		if (acl) {

			struct iattr iattr = {};

			struct posix_acl *acl_mode = acl;



			retval = posix_acl_update_mode(&init_user_ns, inode,

						       &iattr.ia_mode,

						       &acl_mode);

			if (retval)

				goto err_out;

			if (!acl_mode) {

				/*

				 * ACL can be represented by the mode bits.

				 * So don't update ACL below.

				 */

				kfree(value);

				value = NULL;

				size = 0;

			}

			iattr.ia_valid = ATTR_MODE;

			/*

			 * FIXME should we update ctime ?

			 * What is the following setxattr update the mode ?

			 */

			v9fs_vfs_setattr_dotl(&init_user_ns, dentry, &iattr);

		}

		break;

	case ACL_TYPE_DEFAULT:

		if (!S_ISDIR(inode->i_mode)) {

			retval = acl ? -EINVAL : 0;

			goto err_out;

		}

		break;

	}



	retval = v9fs_xattr_set(dentry, acl_name, value, size, 0);

	if (!retval)

		set_cached_acl(inode, type, acl);



err_out:

	kfree(value);

	return retval;

}



static int v9fs_set_acl(struct p9_fid *fid, int type, struct posix_acl *acl)

{

	int retval;
@@ -207,124 +343,3 @@ int v9fs_acl_mode(struct inode *dir, umode_t *modep, 
	*modep  = mode;

	return 0;

}
 


static int v9fs_xattr_get_acl(const struct xattr_handler *handler,

			      struct dentry *dentry, struct inode *inode,

			      const char *name, void *buffer, size_t size)

{

	struct v9fs_session_info *v9ses;

	struct posix_acl *acl;

	int error;



	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_xattr_get(dentry, handler->name, buffer, size);



	acl = v9fs_get_cached_acl(inode, handler->flags);

	if (IS_ERR(acl))

		return PTR_ERR(acl);

	if (acl == NULL)

		return -ENODATA;

	error = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);

	posix_acl_release(acl);



	return error;

}



static int v9fs_xattr_set_acl(const struct xattr_handler *handler,

			      struct user_namespace *mnt_userns,

			      struct dentry *dentry, struct inode *inode,

			      const char *name, const void *value,

			      size_t size, int flags)

{

	int retval;

	struct posix_acl *acl;

	struct v9fs_session_info *v9ses;



	v9ses = v9fs_dentry2v9ses(dentry);

	/*

	 * set the attribute on the remote. Without even looking at the

	 * xattr value. We leave it to the server to validate

	 */

	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)

		return v9fs_xattr_set(dentry, handler->name, value, size,

				      flags);



	if (S_ISLNK(inode->i_mode))

		return -EOPNOTSUPP;

	if (!inode_owner_or_capable(&init_user_ns, inode))

		return -EPERM;

	if (value) {

		/* update the cached acl value */

		acl = posix_acl_from_xattr(&init_user_ns, value, size);

		if (IS_ERR(acl))

			return PTR_ERR(acl);

		else if (acl) {

			retval = posix_acl_valid(inode->i_sb->s_user_ns, acl);

			if (retval)

				goto err_out;

		}

	} else

		acl = NULL;



	switch (handler->flags) {

	case ACL_TYPE_ACCESS:

		if (acl) {

			struct iattr iattr = { 0 };

			struct posix_acl *old_acl = acl;



			retval = posix_acl_update_mode(&init_user_ns, inode,

						       &iattr.ia_mode, &acl);

			if (retval)

				goto err_out;

			if (!acl) {

				/*

				 * ACL can be represented

				 * by the mode bits. So don't

				 * update ACL.

				 */

				posix_acl_release(old_acl);

				value = NULL;

				size = 0;

			}

			iattr.ia_valid = ATTR_MODE;

			/* FIXME should we update ctime ?

			 * What is the following setxattr update the

			 * mode ?

			 */

			v9fs_vfs_setattr_dotl(&init_user_ns, dentry, &iattr);

		}

		break;

	case ACL_TYPE_DEFAULT:

		if (!S_ISDIR(inode->i_mode)) {

			retval = acl ? -EINVAL : 0;

			goto err_out;

		}

		break;

	default:

		BUG();

	}

	retval = v9fs_xattr_set(dentry, handler->name, value, size, flags);

	if (!retval)

		set_cached_acl(inode, handler->flags, acl);

err_out:

	posix_acl_release(acl);

	return retval;

}



const struct xattr_handler v9fs_xattr_acl_access_handler = {

	.name	= XATTR_NAME_POSIX_ACL_ACCESS,

	.flags	= ACL_TYPE_ACCESS,

	.get	= v9fs_xattr_get_acl,

	.set	= v9fs_xattr_set_acl,

};



const struct xattr_handler v9fs_xattr_acl_default_handler = {

	.name	= XATTR_NAME_POSIX_ACL_DEFAULT,

	.flags	= ACL_TYPE_DEFAULT,

	.get	= v9fs_xattr_get_acl,

	.set	= v9fs_xattr_set_acl,

};

fs/9p/acl.h

+7 −1
Original line number Diff line number Diff line
@@ -8,8 +8,12 @@ 


#ifdef CONFIG_9P_FS_POSIX_ACL

int v9fs_get_acl(struct inode *inode, struct p9_fid *fid);

struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type,

struct posix_acl *v9fs_iop_get_inode_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);

int v9fs_iop_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry,

		     struct posix_acl *acl, int type);

int v9fs_acl_chmod(struct inode *inode, struct p9_fid *fid);

int v9fs_set_create_acl(struct inode *inode, struct p9_fid *fid,

			struct posix_acl *dacl, struct posix_acl *acl);
@@ -17,7 +21,9 @@ int v9fs_acl_mode(struct inode *dir, umode_t *modep, 
		  struct posix_acl **dpacl, struct posix_acl **pacl);

void v9fs_put_acl(struct posix_acl *dacl, struct posix_acl *acl);

#else

#define v9fs_iop_get_inode_acl	NULL

#define v9fs_iop_get_acl NULL

#define v9fs_iop_set_acl NULL

static inline int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)

{

	return 0;