[deliverable/linux.git] / fs / xfs / xfs_acl.c

/*
 * Copyright (c) 2008, Christoph Hellwig
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would 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 the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_log_format.h"
#include "xfs_acl.h"
#include "xfs_attr.h"
#include "xfs_bmap_btree.h"
#include "xfs_inode.h"
#include "xfs_vnodeops.h"
#include "xfs_sb.h"
#include "xfs_mount.h"
#include "xfs_trace.h"
#include <linux/slab.h>
#include <linux/xattr.h>
#include <linux/posix_acl_xattr.h>


/*
 * Locking scheme:
 *  - all ACL updates are protected by inode->i_mutex, which is taken before
 *    calling into this file.
 */

STATIC struct posix_acl *
xfs_acl_from_disk(
	struct xfs_acl	*aclp,
	int		max_entries)
{
	struct posix_acl_entry *acl_e;
	struct posix_acl *acl;
	struct xfs_acl_entry *ace;
	unsigned int count, i;

	count = be32_to_cpu(aclp->acl_cnt);
	if (count > max_entries)
		return ERR_PTR(-EFSCORRUPTED);

	acl = posix_acl_alloc(count, GFP_KERNEL);
	if (!acl)
		return ERR_PTR(-ENOMEM);

	for (i = 0; i < count; i++) {
		acl_e = &acl->a_entries[i];
		ace = &aclp->acl_entry[i];

		/*
		 * The tag is 32 bits on disk and 16 bits in core.
		 *
		 * Because every access to it goes through the core
		 * format first this is not a problem.
		 */
		acl_e->e_tag = be32_to_cpu(ace->ae_tag);
		acl_e->e_perm = be16_to_cpu(ace->ae_perm);

		switch (acl_e->e_tag) {
		case ACL_USER:
		case ACL_GROUP:
			acl_e->e_id = be32_to_cpu(ace->ae_id);
			break;
		case ACL_USER_OBJ:
		case ACL_GROUP_OBJ:
		case ACL_MASK:
		case ACL_OTHER:
			acl_e->e_id = ACL_UNDEFINED_ID;
			break;
		default:
			goto fail;
		}
	}
	return acl;

fail:
	posix_acl_release(acl);
	return ERR_PTR(-EINVAL);
}

STATIC void
xfs_acl_to_disk(struct xfs_acl *aclp, const struct posix_acl *acl)
{
	const struct posix_acl_entry *acl_e;
	struct xfs_acl_entry *ace;
	int i;

	aclp->acl_cnt = cpu_to_be32(acl->a_count);
	for (i = 0; i < acl->a_count; i++) {
		ace = &aclp->acl_entry[i];
		acl_e = &acl->a_entries[i];

		ace->ae_tag = cpu_to_be32(acl_e->e_tag);
		ace->ae_id = cpu_to_be32(acl_e->e_id);
		ace->ae_perm = cpu_to_be16(acl_e->e_perm);
	}
}

struct posix_acl *
xfs_get_acl(struct inode *inode, int type)
{
	struct xfs_inode *ip = XFS_I(inode);
	struct posix_acl *acl;
	struct xfs_acl *xfs_acl;
	unsigned char *ea_name;
	int error;
	int len;

	acl = get_cached_acl(inode, type);
	if (acl != ACL_NOT_CACHED)
		return acl;

	trace_xfs_get_acl(ip);

	switch (type) {
	case ACL_TYPE_ACCESS:
		ea_name = SGI_ACL_FILE;
		break;
	case ACL_TYPE_DEFAULT:
		ea_name = SGI_ACL_DEFAULT;
		break;
	default:
		BUG();
	}

	/*
	 * If we have a cached ACLs value just return it, not need to
	 * go out to the disk.
	 */
	len = XFS_ACL_MAX_SIZE(ip->i_mount);
	xfs_acl = kzalloc(len, GFP_KERNEL);
	if (!xfs_acl)
		return ERR_PTR(-ENOMEM);

	error = -xfs_attr_get(ip, ea_name, (unsigned char *)xfs_acl,
							&len, ATTR_ROOT);
	if (error) {
		/*
		 * If the attribute doesn't exist make sure we have a negative
		 * cache entry, for any other error assume it is transient and
		 * leave the cache entry as ACL_NOT_CACHED.
		 */
		if (error == -ENOATTR) {
			acl = NULL;
			goto out_update_cache;
		}
		goto out;
	}

	acl = xfs_acl_from_disk(xfs_acl, XFS_ACL_MAX_ENTRIES(ip->i_mount));
	if (IS_ERR(acl))
		goto out;

 out_update_cache:
	set_cached_acl(inode, type, acl);
 out:
	kfree(xfs_acl);
	return acl;
}

STATIC int
xfs_set_acl(struct inode *inode, int type, struct posix_acl *acl)
{
	struct xfs_inode *ip = XFS_I(inode);
	unsigned char *ea_name;
	int error;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	switch (type) {
	case ACL_TYPE_ACCESS:
		ea_name = SGI_ACL_FILE;
		break;
	case ACL_TYPE_DEFAULT:
		if (!S_ISDIR(inode->i_mode))
			return acl ? -EACCES : 0;
		ea_name = SGI_ACL_DEFAULT;
		break;
	default:
		return -EINVAL;
	}

	if (acl) {
		struct xfs_acl *xfs_acl;
		int len = XFS_ACL_MAX_SIZE(ip->i_mount);

		xfs_acl = kzalloc(len, GFP_KERNEL);
		if (!xfs_acl)
			return -ENOMEM;

		xfs_acl_to_disk(xfs_acl, acl);

		/* subtract away the unused acl entries */
		len -= sizeof(struct xfs_acl_entry) *
			 (XFS_ACL_MAX_ENTRIES(ip->i_mount) - acl->a_count);

		error = -xfs_attr_set(ip, ea_name, (unsigned char *)xfs_acl,
				len, ATTR_ROOT);

		kfree(xfs_acl);
	} else {
		/*
		 * A NULL ACL argument means we want to remove the ACL.
		 */
		error = -xfs_attr_remove(ip, ea_name, ATTR_ROOT);

		/*
		 * If the attribute didn't exist to start with that's fine.
		 */
		if (error == -ENOATTR)
			error = 0;
	}

	if (!error)
		set_cached_acl(inode, type, acl);
	return error;
}

static int
xfs_set_mode(struct inode *inode, umode_t mode)
{
	int error = 0;

	if (mode != inode->i_mode) {
		struct iattr iattr;

		iattr.ia_valid = ATTR_MODE | ATTR_CTIME;
		iattr.ia_mode = mode;
		iattr.ia_ctime = current_fs_time(inode->i_sb);

		error = -xfs_setattr_nonsize(XFS_I(inode), &iattr, XFS_ATTR_NOACL);
	}

	return error;
}

static int
xfs_acl_exists(struct inode *inode, unsigned char *name)
{
	int len = XFS_ACL_MAX_SIZE(XFS_M(inode->i_sb));

	return (xfs_attr_get(XFS_I(inode), name, NULL, &len,
			    ATTR_ROOT|ATTR_KERNOVAL) == 0);
}

int
posix_acl_access_exists(struct inode *inode)
{
	return xfs_acl_exists(inode, SGI_ACL_FILE);
}

int
posix_acl_default_exists(struct inode *inode)
{
	if (!S_ISDIR(inode->i_mode))
		return 0;
	return xfs_acl_exists(inode, SGI_ACL_DEFAULT);
}

/*
 * No need for i_mutex because the inode is not yet exposed to the VFS.
 */
int
xfs_inherit_acl(struct inode *inode, struct posix_acl *acl)
{
	umode_t mode = inode->i_mode;
	int error = 0, inherit = 0;

	if (S_ISDIR(inode->i_mode)) {
		error = xfs_set_acl(inode, ACL_TYPE_DEFAULT, acl);
		if (error)
			goto out;
	}

	error = posix_acl_create(&acl, GFP_KERNEL, &mode);
	if (error < 0)
		return error;

	/*
	 * If posix_acl_create returns a positive value we need to
	 * inherit a permission that can't be represented using the Unix
	 * mode bits and we actually need to set an ACL.
	 */
	if (error > 0)
		inherit = 1;

	error = xfs_set_mode(inode, mode);
	if (error)
		goto out;

	if (inherit)
		error = xfs_set_acl(inode, ACL_TYPE_ACCESS, acl);

out:
	posix_acl_release(acl);
	return error;
}

int
xfs_acl_chmod(struct inode *inode)
{
	struct posix_acl *acl;
	int error;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	acl = xfs_get_acl(inode, ACL_TYPE_ACCESS);
	if (IS_ERR(acl) || !acl)
		return PTR_ERR(acl);

	error = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
	if (error)
		return error;

	error = xfs_set_acl(inode, ACL_TYPE_ACCESS, acl);
	posix_acl_release(acl);
	return error;
}

static int
xfs_xattr_acl_get(struct dentry *dentry, const char *name,
		void *value, size_t size, int type)
{
	struct posix_acl *acl;
	int error;

	acl = xfs_get_acl(dentry->d_inode, type);
	if (IS_ERR(acl))
		return PTR_ERR(acl);
	if (acl == NULL)
		return -ENODATA;

	error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
	posix_acl_release(acl);

	return error;
}

static int
xfs_xattr_acl_set(struct dentry *dentry, const char *name,
		const void *value, size_t size, int flags, int type)
{
	struct inode *inode = dentry->d_inode;
	struct posix_acl *acl = NULL;
	int error = 0;

	if (flags & XATTR_CREATE)
		return -EINVAL;
	if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
		return value ? -EACCES : 0;
	if ((current_fsuid() != inode->i_uid) && !capable(CAP_FOWNER))
		return -EPERM;

	if (!value)
		goto set_acl;

	acl = posix_acl_from_xattr(&init_user_ns, value, size);
	if (!acl) {
		/*
		 * acl_set_file(3) may request that we set default ACLs with
		 * zero length -- defend (gracefully) against that here.
		 */
		goto out;
	}
	if (IS_ERR(acl)) {
		error = PTR_ERR(acl);
		goto out;
	}

	error = posix_acl_valid(acl);
	if (error)
		goto out_release;

	error = -EINVAL;
	if (acl->a_count > XFS_ACL_MAX_ENTRIES(XFS_M(inode->i_sb)))
		goto out_release;

	if (type == ACL_TYPE_ACCESS) {
		umode_t mode = inode->i_mode;
		error = posix_acl_equiv_mode(acl, &mode);

		if (error <= 0) {
			posix_acl_release(acl);
			acl = NULL;

			if (error < 0)
				return error;
		}

		error = xfs_set_mode(inode, mode);
		if (error)
			goto out_release;
	}

 set_acl:
	error = xfs_set_acl(inode, type, acl);
 out_release:
	posix_acl_release(acl);
 out:
	return error;
}

const struct xattr_handler xfs_xattr_acl_access_handler = {
	.prefix	= POSIX_ACL_XATTR_ACCESS,
	.flags	= ACL_TYPE_ACCESS,
	.get	= xfs_xattr_acl_get,
	.set	= xfs_xattr_acl_set,
};

const struct xattr_handler xfs_xattr_acl_default_handler = {
	.prefix	= POSIX_ACL_XATTR_DEFAULT,
	.flags	= ACL_TYPE_DEFAULT,
	.get	= xfs_xattr_acl_get,
	.set	= xfs_xattr_acl_set,
};
Commit	Line	Data
ef14f0c1 CH	1	/*
	2	* Copyright (c) 2008, Christoph Hellwig
	3	* All Rights Reserved.
	4	*
	5	* This program is free software; you can redistribute it and/or
	6	* modify it under the terms of the GNU General Public License as
	7	* published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope that it would be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write the Free Software Foundation,
	16	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	17	*/
	18	#include "xfs.h"
69432832	19	#include "xfs_log_format.h"
ef14f0c1 CH	20	#include "xfs_acl.h"
	21	#include "xfs_attr.h"
	22	#include "xfs_bmap_btree.h"
	23	#include "xfs_inode.h"
	24	#include "xfs_vnodeops.h"
0a8aa193 DC	25	#include "xfs_sb.h"
0a8aa193 DC	26	#include "xfs_mount.h"
0b1b213f	27	#include "xfs_trace.h"
5a0e3ad6	28	#include <linux/slab.h>
ef14f0c1 CH	29	#include <linux/xattr.h>
	30	#include <linux/posix_acl_xattr.h>
	31
	32
ef14f0c1 CH	33	/*
	34	* Locking scheme:
	35	* - all ACL updates are protected by inode->i_mutex, which is taken before
	36	* calling into this file.
ef14f0c1 CH	37	*/
	38
	39	STATIC struct posix_acl *
0a8aa193 DC	40	xfs_acl_from_disk(
	41	struct xfs_acl *aclp,
	42	int max_entries)
ef14f0c1 CH	43	{
	44	struct posix_acl_entry *acl_e;
	45	struct posix_acl *acl;
	46	struct xfs_acl_entry *ace;
093019cf	47	unsigned int count, i;
ef14f0c1 CH	48
ef14f0c1 CH	49	count = be32_to_cpu(aclp->acl_cnt);
0a8aa193	50	if (count > max_entries)
fa8b18ed	51	return ERR_PTR(-EFSCORRUPTED);
ef14f0c1 CH	52
	53	acl = posix_acl_alloc(count, GFP_KERNEL);
	54	if (!acl)
	55	return ERR_PTR(-ENOMEM);
	56
	57	for (i = 0; i < count; i++) {
	58	acl_e = &acl->a_entries[i];
	59	ace = &aclp->acl_entry[i];
	60
	61	/*
	62	* The tag is 32 bits on disk and 16 bits in core.
	63	*
	64	* Because every access to it goes through the core
	65	* format first this is not a problem.
	66	*/
	67	acl_e->e_tag = be32_to_cpu(ace->ae_tag);
	68	acl_e->e_perm = be16_to_cpu(ace->ae_perm);
	69
	70	switch (acl_e->e_tag) {
	71	case ACL_USER:
	72	case ACL_GROUP:
	73	acl_e->e_id = be32_to_cpu(ace->ae_id);
	74	break;
	75	case ACL_USER_OBJ:
	76	case ACL_GROUP_OBJ:
	77	case ACL_MASK:
	78	case ACL_OTHER:
	79	acl_e->e_id = ACL_UNDEFINED_ID;
	80	break;
	81	default:
	82	goto fail;
	83	}
	84	}
	85	return acl;
	86
	87	fail:
	88	posix_acl_release(acl);
	89	return ERR_PTR(-EINVAL);
	90	}
	91
	92	STATIC void
	93	xfs_acl_to_disk(struct xfs_acl aclp, const struct posix_acl acl)
	94	{
	95	const struct posix_acl_entry *acl_e;
	96	struct xfs_acl_entry *ace;
	97	int i;
	98
	99	aclp->acl_cnt = cpu_to_be32(acl->a_count);
	100	for (i = 0; i < acl->a_count; i++) {
	101	ace = &aclp->acl_entry[i];
	102	acl_e = &acl->a_entries[i];
	103
	104	ace->ae_tag = cpu_to_be32(acl_e->e_tag);
	105	ace->ae_id = cpu_to_be32(acl_e->e_id);
	106	ace->ae_perm = cpu_to_be16(acl_e->e_perm);
	107	}
	108	}
	109
ef14f0c1 CH	110	struct posix_acl *
	111	xfs_get_acl(struct inode *inode, int type)
	112	{
	113	struct xfs_inode *ip = XFS_I(inode);
1cbd20d8	114	struct posix_acl *acl;
ef14f0c1	115	struct xfs_acl *xfs_acl;
a9273ca5	116	unsigned char *ea_name;
ef14f0c1	117	int error;
0a8aa193	118	int len;
ef14f0c1	119
1cbd20d8 AV	120	acl = get_cached_acl(inode, type);
	121	if (acl != ACL_NOT_CACHED)
	122	return acl;
	123
4e34e719 CH	124	trace_xfs_get_acl(ip);
4e34e719 CH	125
ef14f0c1 CH	126	switch (type) {
	127	case ACL_TYPE_ACCESS:
	128	ea_name = SGI_ACL_FILE;
ef14f0c1 CH	129	break;
	130	case ACL_TYPE_DEFAULT:
	131	ea_name = SGI_ACL_DEFAULT;
ef14f0c1 CH	132	break;
ef14f0c1 CH	133	default:
1cbd20d8	134	BUG();
ef14f0c1 CH	135	}
ef14f0c1 CH	136
ef14f0c1 CH	137	/*
	138	* If we have a cached ACLs value just return it, not need to
	139	* go out to the disk.
	140	*/
0a8aa193 DC	141	len = XFS_ACL_MAX_SIZE(ip->i_mount);
0a8aa193 DC	142	xfs_acl = kzalloc(len, GFP_KERNEL);
ef14f0c1 CH	143	if (!xfs_acl)
	144	return ERR_PTR(-ENOMEM);
	145
a9273ca5 DC	146	error = -xfs_attr_get(ip, ea_name, (unsigned char *)xfs_acl,
a9273ca5 DC	147	&len, ATTR_ROOT);
ef14f0c1 CH	148	if (error) {
	149	/*
	150	* If the attribute doesn't exist make sure we have a negative
	151	* cache entry, for any other error assume it is transient and
1cbd20d8	152	* leave the cache entry as ACL_NOT_CACHED.
ef14f0c1 CH	153	*/
	154	if (error == -ENOATTR) {
	155	acl = NULL;
	156	goto out_update_cache;
	157	}
	158	goto out;
	159	}
	160
0a8aa193	161	acl = xfs_acl_from_disk(xfs_acl, XFS_ACL_MAX_ENTRIES(ip->i_mount));
ef14f0c1 CH	162	if (IS_ERR(acl))
	163	goto out;
	164
	165	out_update_cache:
1cbd20d8	166	set_cached_acl(inode, type, acl);
ef14f0c1 CH	167	out:
	168	kfree(xfs_acl);
	169	return acl;
	170	}
	171
	172	STATIC int
	173	xfs_set_acl(struct inode inode, int type, struct posix_acl acl)
	174	{
	175	struct xfs_inode *ip = XFS_I(inode);
a9273ca5	176	unsigned char *ea_name;
ef14f0c1 CH	177	int error;
	178
	179	if (S_ISLNK(inode->i_mode))
	180	return -EOPNOTSUPP;
	181
	182	switch (type) {
	183	case ACL_TYPE_ACCESS:
	184	ea_name = SGI_ACL_FILE;
ef14f0c1 CH	185	break;
	186	case ACL_TYPE_DEFAULT:
	187	if (!S_ISDIR(inode->i_mode))
	188	return acl ? -EACCES : 0;
	189	ea_name = SGI_ACL_DEFAULT;
ef14f0c1 CH	190	break;
	191	default:
	192	return -EINVAL;
	193	}
	194
	195	if (acl) {
	196	struct xfs_acl *xfs_acl;
0a8aa193	197	int len = XFS_ACL_MAX_SIZE(ip->i_mount);
ef14f0c1	198
0a8aa193	199	xfs_acl = kzalloc(len, GFP_KERNEL);
ef14f0c1 CH	200	if (!xfs_acl)
	201	return -ENOMEM;
	202
	203	xfs_acl_to_disk(xfs_acl, acl);
0a8aa193 DC	204
	205	/* subtract away the unused acl entries */
	206	len -= sizeof(struct xfs_acl_entry) *
	207	(XFS_ACL_MAX_ENTRIES(ip->i_mount) - acl->a_count);
ef14f0c1	208
a9273ca5	209	error = -xfs_attr_set(ip, ea_name, (unsigned char *)xfs_acl,
ef14f0c1 CH	210	len, ATTR_ROOT);
	211
	212	kfree(xfs_acl);
	213	} else {
	214	/*
	215	* A NULL ACL argument means we want to remove the ACL.
	216	*/
	217	error = -xfs_attr_remove(ip, ea_name, ATTR_ROOT);
	218
	219	/*
	220	* If the attribute didn't exist to start with that's fine.
	221	*/
	222	if (error == -ENOATTR)
	223	error = 0;
	224	}
	225
	226	if (!error)
1cbd20d8	227	set_cached_acl(inode, type, acl);
ef14f0c1 CH	228	return error;
	229	}
	230
ef14f0c1	231	static int
d3fb6120	232	xfs_set_mode(struct inode *inode, umode_t mode)
ef14f0c1 CH	233	{
	234	int error = 0;
	235
	236	if (mode != inode->i_mode) {
	237	struct iattr iattr;
	238
d6d59bad	239	iattr.ia_valid = ATTR_MODE \| ATTR_CTIME;
ef14f0c1	240	iattr.ia_mode = mode;
d6d59bad	241	iattr.ia_ctime = current_fs_time(inode->i_sb);
ef14f0c1	242
c4ed4243	243	error = -xfs_setattr_nonsize(XFS_I(inode), &iattr, XFS_ATTR_NOACL);
ef14f0c1 CH	244	}
	245
	246	return error;
	247	}
	248
	249	static int
a9273ca5	250	xfs_acl_exists(struct inode inode, unsigned char name)
ef14f0c1	251	{
0a8aa193	252	int len = XFS_ACL_MAX_SIZE(XFS_M(inode->i_sb));
ef14f0c1 CH	253
	254	return (xfs_attr_get(XFS_I(inode), name, NULL, &len,
	255	ATTR_ROOT\|ATTR_KERNOVAL) == 0);
	256	}
	257
	258	int
	259	posix_acl_access_exists(struct inode *inode)
	260	{
	261	return xfs_acl_exists(inode, SGI_ACL_FILE);
	262	}
	263
	264	int
	265	posix_acl_default_exists(struct inode *inode)
	266	{
	267	if (!S_ISDIR(inode->i_mode))
	268	return 0;
	269	return xfs_acl_exists(inode, SGI_ACL_DEFAULT);
	270	}
	271
	272	/*
	273	* No need for i_mutex because the inode is not yet exposed to the VFS.
	274	*/
	275	int
826cae2f	276	xfs_inherit_acl(struct inode inode, struct posix_acl acl)
ef14f0c1	277	{
d3fb6120	278	umode_t mode = inode->i_mode;
ef14f0c1 CH	279	int error = 0, inherit = 0;
	280
	281	if (S_ISDIR(inode->i_mode)) {
826cae2f	282	error = xfs_set_acl(inode, ACL_TYPE_DEFAULT, acl);
ef14f0c1	283	if (error)
826cae2f	284	goto out;
ef14f0c1 CH	285	}
ef14f0c1 CH	286
826cae2f	287	error = posix_acl_create(&acl, GFP_KERNEL, &mode);
ef14f0c1	288	if (error < 0)
826cae2f	289	return error;
ef14f0c1 CH	290
ef14f0c1 CH	291	/*
826cae2f	292	* If posix_acl_create returns a positive value we need to
ef14f0c1 CH	293	* inherit a permission that can't be represented using the Unix
	294	* mode bits and we actually need to set an ACL.
	295	*/
	296	if (error > 0)
	297	inherit = 1;
	298
	299	error = xfs_set_mode(inode, mode);
	300	if (error)
826cae2f	301	goto out;
ef14f0c1 CH	302
ef14f0c1 CH	303	if (inherit)
826cae2f	304	error = xfs_set_acl(inode, ACL_TYPE_ACCESS, acl);
ef14f0c1	305
826cae2f AV	306	out:
826cae2f AV	307	posix_acl_release(acl);
ef14f0c1 CH	308	return error;
	309	}
	310
	311	int
	312	xfs_acl_chmod(struct inode *inode)
	313	{
bc26ab5f	314	struct posix_acl *acl;
ef14f0c1 CH	315	int error;
	316
	317	if (S_ISLNK(inode->i_mode))
	318	return -EOPNOTSUPP;
	319
	320	acl = xfs_get_acl(inode, ACL_TYPE_ACCESS);
	321	if (IS_ERR(acl) \|\| !acl)
	322	return PTR_ERR(acl);
	323
bc26ab5f AV	324	error = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
	325	if (error)
	326	return error;
ef14f0c1	327
bc26ab5f AV	328	error = xfs_set_acl(inode, ACL_TYPE_ACCESS, acl);
bc26ab5f AV	329	posix_acl_release(acl);
ef14f0c1 CH	330	return error;
	331	}
	332
ef14f0c1	333	static int
431547b3 CH	334	xfs_xattr_acl_get(struct dentry dentry, const char name,
431547b3 CH	335	void *value, size_t size, int type)
ef14f0c1 CH	336	{
ef14f0c1 CH	337	struct posix_acl *acl;
431547b3	338	int error;
ef14f0c1	339
431547b3	340	acl = xfs_get_acl(dentry->d_inode, type);
ef14f0c1 CH	341	if (IS_ERR(acl))
	342	return PTR_ERR(acl);
	343	if (acl == NULL)
	344	return -ENODATA;
	345
5f3a4a28	346	error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
ef14f0c1 CH	347	posix_acl_release(acl);
	348
	349	return error;
	350	}
	351
	352	static int
431547b3 CH	353	xfs_xattr_acl_set(struct dentry dentry, const char name,
431547b3 CH	354	const void *value, size_t size, int flags, int type)
ef14f0c1	355	{
431547b3	356	struct inode *inode = dentry->d_inode;
ef14f0c1	357	struct posix_acl *acl = NULL;
431547b3	358	int error = 0;
ef14f0c1	359
ef14f0c1 CH	360	if (flags & XATTR_CREATE)
	361	return -EINVAL;
	362	if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
	363	return value ? -EACCES : 0;
	364	if ((current_fsuid() != inode->i_uid) && !capable(CAP_FOWNER))
	365	return -EPERM;
	366
	367	if (!value)
	368	goto set_acl;
	369
5f3a4a28	370	acl = posix_acl_from_xattr(&init_user_ns, value, size);
ef14f0c1 CH	371	if (!acl) {
	372	/*
	373	* acl_set_file(3) may request that we set default ACLs with
	374	* zero length -- defend (gracefully) against that here.
	375	*/
	376	goto out;
	377	}
	378	if (IS_ERR(acl)) {
	379	error = PTR_ERR(acl);
	380	goto out;
	381	}
	382
	383	error = posix_acl_valid(acl);
	384	if (error)
	385	goto out_release;
	386
	387	error = -EINVAL;
0a8aa193	388	if (acl->a_count > XFS_ACL_MAX_ENTRIES(XFS_M(inode->i_sb)))
ef14f0c1 CH	389	goto out_release;
	390
	391	if (type == ACL_TYPE_ACCESS) {
d6952123	392	umode_t mode = inode->i_mode;
ef14f0c1 CH	393	error = posix_acl_equiv_mode(acl, &mode);
	394
	395	if (error <= 0) {
	396	posix_acl_release(acl);
	397	acl = NULL;
	398
	399	if (error < 0)
	400	return error;
	401	}
	402
	403	error = xfs_set_mode(inode, mode);
	404	if (error)
	405	goto out_release;
	406	}
	407
	408	set_acl:
	409	error = xfs_set_acl(inode, type, acl);
	410	out_release:
	411	posix_acl_release(acl);
	412	out:
	413	return error;
	414	}
	415
46e58764	416	const struct xattr_handler xfs_xattr_acl_access_handler = {
431547b3 CH	417	.prefix = POSIX_ACL_XATTR_ACCESS,
	418	.flags = ACL_TYPE_ACCESS,
	419	.get = xfs_xattr_acl_get,
	420	.set = xfs_xattr_acl_set,
	421	};
	422
46e58764	423	const struct xattr_handler xfs_xattr_acl_default_handler = {
431547b3 CH	424	.prefix = POSIX_ACL_XATTR_DEFAULT,
	425	.flags = ACL_TYPE_DEFAULT,
	426	.get = xfs_xattr_acl_get,
	427	.set = xfs_xattr_acl_set,
ef14f0c1	428	};