[mirror_ubuntu-artful-kernel.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_trans_resv.h"
#include "xfs_acl.h"
#include "xfs_attr.h"
#include "xfs_bmap_btree.h"
#include "xfs_inode.h"
#include "xfs_ag.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"
7fd36c44	20	#include "xfs_trans_resv.h"
ef14f0c1 CH	21	#include "xfs_acl.h"
	22	#include "xfs_attr.h"
	23	#include "xfs_bmap_btree.h"
	24	#include "xfs_inode.h"
9356fe22	25	#include "xfs_ag.h"
0a8aa193 DC	26	#include "xfs_sb.h"
0a8aa193 DC	27	#include "xfs_mount.h"
0b1b213f	28	#include "xfs_trace.h"
5a0e3ad6	29	#include <linux/slab.h>
ef14f0c1 CH	30	#include <linux/xattr.h>
	31	#include <linux/posix_acl_xattr.h>
	32
	33
ef14f0c1 CH	34	/*
	35	* Locking scheme:
	36	* - all ACL updates are protected by inode->i_mutex, which is taken before
	37	* calling into this file.
ef14f0c1 CH	38	*/
	39
	40	STATIC struct posix_acl *
0a8aa193 DC	41	xfs_acl_from_disk(
	42	struct xfs_acl *aclp,
	43	int max_entries)
ef14f0c1 CH	44	{
	45	struct posix_acl_entry *acl_e;
	46	struct posix_acl *acl;
	47	struct xfs_acl_entry *ace;
093019cf	48	unsigned int count, i;
ef14f0c1 CH	49
ef14f0c1 CH	50	count = be32_to_cpu(aclp->acl_cnt);
0a8aa193	51	if (count > max_entries)
fa8b18ed	52	return ERR_PTR(-EFSCORRUPTED);
ef14f0c1 CH	53
	54	acl = posix_acl_alloc(count, GFP_KERNEL);
	55	if (!acl)
	56	return ERR_PTR(-ENOMEM);
	57
	58	for (i = 0; i < count; i++) {
	59	acl_e = &acl->a_entries[i];
	60	ace = &aclp->acl_entry[i];
	61
	62	/*
	63	* The tag is 32 bits on disk and 16 bits in core.
	64	*
	65	* Because every access to it goes through the core
	66	* format first this is not a problem.
	67	*/
	68	acl_e->e_tag = be32_to_cpu(ace->ae_tag);
	69	acl_e->e_perm = be16_to_cpu(ace->ae_perm);
	70
	71	switch (acl_e->e_tag) {
	72	case ACL_USER:
	73	case ACL_GROUP:
	74	acl_e->e_id = be32_to_cpu(ace->ae_id);
	75	break;
	76	case ACL_USER_OBJ:
	77	case ACL_GROUP_OBJ:
	78	case ACL_MASK:
	79	case ACL_OTHER:
	80	acl_e->e_id = ACL_UNDEFINED_ID;
	81	break;
	82	default:
	83	goto fail;
	84	}
	85	}
	86	return acl;
	87
	88	fail:
	89	posix_acl_release(acl);
	90	return ERR_PTR(-EINVAL);
	91	}
	92
	93	STATIC void
	94	xfs_acl_to_disk(struct xfs_acl aclp, const struct posix_acl acl)
	95	{
	96	const struct posix_acl_entry *acl_e;
	97	struct xfs_acl_entry *ace;
	98	int i;
	99
	100	aclp->acl_cnt = cpu_to_be32(acl->a_count);
	101	for (i = 0; i < acl->a_count; i++) {
	102	ace = &aclp->acl_entry[i];
	103	acl_e = &acl->a_entries[i];
	104
	105	ace->ae_tag = cpu_to_be32(acl_e->e_tag);
	106	ace->ae_id = cpu_to_be32(acl_e->e_id);
	107	ace->ae_perm = cpu_to_be16(acl_e->e_perm);
	108	}
	109	}
	110
ef14f0c1 CH	111	struct posix_acl *
	112	xfs_get_acl(struct inode *inode, int type)
	113	{
	114	struct xfs_inode *ip = XFS_I(inode);
1cbd20d8	115	struct posix_acl *acl;
ef14f0c1	116	struct xfs_acl *xfs_acl;
a9273ca5	117	unsigned char *ea_name;
ef14f0c1	118	int error;
0a8aa193	119	int len;
ef14f0c1	120
1cbd20d8 AV	121	acl = get_cached_acl(inode, type);
	122	if (acl != ACL_NOT_CACHED)
	123	return acl;
	124
4e34e719 CH	125	trace_xfs_get_acl(ip);
4e34e719 CH	126
ef14f0c1 CH	127	switch (type) {
	128	case ACL_TYPE_ACCESS:
	129	ea_name = SGI_ACL_FILE;
ef14f0c1 CH	130	break;
	131	case ACL_TYPE_DEFAULT:
	132	ea_name = SGI_ACL_DEFAULT;
ef14f0c1 CH	133	break;
ef14f0c1 CH	134	default:
1cbd20d8	135	BUG();
ef14f0c1 CH	136	}
ef14f0c1 CH	137
ef14f0c1 CH	138	/*
	139	* If we have a cached ACLs value just return it, not need to
	140	* go out to the disk.
	141	*/
0a8aa193 DC	142	len = XFS_ACL_MAX_SIZE(ip->i_mount);
0a8aa193 DC	143	xfs_acl = kzalloc(len, GFP_KERNEL);
ef14f0c1 CH	144	if (!xfs_acl)
	145	return ERR_PTR(-ENOMEM);
	146
a9273ca5 DC	147	error = -xfs_attr_get(ip, ea_name, (unsigned char *)xfs_acl,
a9273ca5 DC	148	&len, ATTR_ROOT);
ef14f0c1 CH	149	if (error) {
	150	/*
	151	* If the attribute doesn't exist make sure we have a negative
	152	* cache entry, for any other error assume it is transient and
1cbd20d8	153	* leave the cache entry as ACL_NOT_CACHED.
ef14f0c1 CH	154	*/
	155	if (error == -ENOATTR) {
	156	acl = NULL;
	157	goto out_update_cache;
	158	}
	159	goto out;
	160	}
	161
0a8aa193	162	acl = xfs_acl_from_disk(xfs_acl, XFS_ACL_MAX_ENTRIES(ip->i_mount));
ef14f0c1 CH	163	if (IS_ERR(acl))
	164	goto out;
	165
	166	out_update_cache:
1cbd20d8	167	set_cached_acl(inode, type, acl);
ef14f0c1 CH	168	out:
	169	kfree(xfs_acl);
	170	return acl;
	171	}
	172
	173	STATIC int
	174	xfs_set_acl(struct inode inode, int type, struct posix_acl acl)
	175	{
	176	struct xfs_inode *ip = XFS_I(inode);
a9273ca5	177	unsigned char *ea_name;
ef14f0c1 CH	178	int error;
	179
	180	if (S_ISLNK(inode->i_mode))
	181	return -EOPNOTSUPP;
	182
	183	switch (type) {
	184	case ACL_TYPE_ACCESS:
	185	ea_name = SGI_ACL_FILE;
ef14f0c1 CH	186	break;
	187	case ACL_TYPE_DEFAULT:
	188	if (!S_ISDIR(inode->i_mode))
	189	return acl ? -EACCES : 0;
	190	ea_name = SGI_ACL_DEFAULT;
ef14f0c1 CH	191	break;
	192	default:
	193	return -EINVAL;
	194	}
	195
	196	if (acl) {
	197	struct xfs_acl *xfs_acl;
0a8aa193	198	int len = XFS_ACL_MAX_SIZE(ip->i_mount);
ef14f0c1	199
0a8aa193	200	xfs_acl = kzalloc(len, GFP_KERNEL);
ef14f0c1 CH	201	if (!xfs_acl)
	202	return -ENOMEM;
	203
	204	xfs_acl_to_disk(xfs_acl, acl);
0a8aa193 DC	205
	206	/* subtract away the unused acl entries */
	207	len -= sizeof(struct xfs_acl_entry) *
	208	(XFS_ACL_MAX_ENTRIES(ip->i_mount) - acl->a_count);
ef14f0c1	209
a9273ca5	210	error = -xfs_attr_set(ip, ea_name, (unsigned char *)xfs_acl,
ef14f0c1 CH	211	len, ATTR_ROOT);
	212
	213	kfree(xfs_acl);
	214	} else {
	215	/*
	216	* A NULL ACL argument means we want to remove the ACL.
	217	*/
	218	error = -xfs_attr_remove(ip, ea_name, ATTR_ROOT);
	219
	220	/*
	221	* If the attribute didn't exist to start with that's fine.
	222	*/
	223	if (error == -ENOATTR)
	224	error = 0;
	225	}
	226
	227	if (!error)
1cbd20d8	228	set_cached_acl(inode, type, acl);
ef14f0c1 CH	229	return error;
	230	}
	231
ef14f0c1	232	static int
d3fb6120	233	xfs_set_mode(struct inode *inode, umode_t mode)
ef14f0c1 CH	234	{
	235	int error = 0;
	236
	237	if (mode != inode->i_mode) {
	238	struct iattr iattr;
	239
d6d59bad	240	iattr.ia_valid = ATTR_MODE \| ATTR_CTIME;
ef14f0c1	241	iattr.ia_mode = mode;
d6d59bad	242	iattr.ia_ctime = current_fs_time(inode->i_sb);
ef14f0c1	243
c4ed4243	244	error = -xfs_setattr_nonsize(XFS_I(inode), &iattr, XFS_ATTR_NOACL);
ef14f0c1 CH	245	}
	246
	247	return error;
	248	}
	249
	250	static int
a9273ca5	251	xfs_acl_exists(struct inode inode, unsigned char name)
ef14f0c1	252	{
0a8aa193	253	int len = XFS_ACL_MAX_SIZE(XFS_M(inode->i_sb));
ef14f0c1 CH	254
	255	return (xfs_attr_get(XFS_I(inode), name, NULL, &len,
	256	ATTR_ROOT\|ATTR_KERNOVAL) == 0);
	257	}
	258
	259	int
	260	posix_acl_access_exists(struct inode *inode)
	261	{
	262	return xfs_acl_exists(inode, SGI_ACL_FILE);
	263	}
	264
	265	int
	266	posix_acl_default_exists(struct inode *inode)
	267	{
	268	if (!S_ISDIR(inode->i_mode))
	269	return 0;
	270	return xfs_acl_exists(inode, SGI_ACL_DEFAULT);
	271	}
	272
	273	/*
	274	* No need for i_mutex because the inode is not yet exposed to the VFS.
	275	*/
	276	int
826cae2f	277	xfs_inherit_acl(struct inode inode, struct posix_acl acl)
ef14f0c1	278	{
d3fb6120	279	umode_t mode = inode->i_mode;
ef14f0c1 CH	280	int error = 0, inherit = 0;
	281
	282	if (S_ISDIR(inode->i_mode)) {
826cae2f	283	error = xfs_set_acl(inode, ACL_TYPE_DEFAULT, acl);
ef14f0c1	284	if (error)
826cae2f	285	goto out;
ef14f0c1 CH	286	}
ef14f0c1 CH	287
826cae2f	288	error = posix_acl_create(&acl, GFP_KERNEL, &mode);
ef14f0c1	289	if (error < 0)
826cae2f	290	return error;
ef14f0c1 CH	291
ef14f0c1 CH	292	/*
826cae2f	293	* If posix_acl_create returns a positive value we need to
ef14f0c1 CH	294	* inherit a permission that can't be represented using the Unix
	295	* mode bits and we actually need to set an ACL.
	296	*/
	297	if (error > 0)
	298	inherit = 1;
	299
	300	error = xfs_set_mode(inode, mode);
	301	if (error)
826cae2f	302	goto out;
ef14f0c1 CH	303
ef14f0c1 CH	304	if (inherit)
826cae2f	305	error = xfs_set_acl(inode, ACL_TYPE_ACCESS, acl);
ef14f0c1	306
826cae2f AV	307	out:
826cae2f AV	308	posix_acl_release(acl);
ef14f0c1 CH	309	return error;
	310	}
	311
	312	int
	313	xfs_acl_chmod(struct inode *inode)
	314	{
bc26ab5f	315	struct posix_acl *acl;
ef14f0c1 CH	316	int error;
	317
	318	if (S_ISLNK(inode->i_mode))
	319	return -EOPNOTSUPP;
	320
	321	acl = xfs_get_acl(inode, ACL_TYPE_ACCESS);
	322	if (IS_ERR(acl) \|\| !acl)
	323	return PTR_ERR(acl);
	324
bc26ab5f AV	325	error = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
	326	if (error)
	327	return error;
ef14f0c1	328
bc26ab5f AV	329	error = xfs_set_acl(inode, ACL_TYPE_ACCESS, acl);
bc26ab5f AV	330	posix_acl_release(acl);
ef14f0c1 CH	331	return error;
	332	}
	333
ef14f0c1	334	static int
431547b3 CH	335	xfs_xattr_acl_get(struct dentry dentry, const char name,
431547b3 CH	336	void *value, size_t size, int type)
ef14f0c1 CH	337	{
ef14f0c1 CH	338	struct posix_acl *acl;
431547b3	339	int error;
ef14f0c1	340
431547b3	341	acl = xfs_get_acl(dentry->d_inode, type);
ef14f0c1 CH	342	if (IS_ERR(acl))
	343	return PTR_ERR(acl);
	344	if (acl == NULL)
	345	return -ENODATA;
	346
5f3a4a28	347	error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
ef14f0c1 CH	348	posix_acl_release(acl);
	349
	350	return error;
	351	}
	352
	353	static int
431547b3 CH	354	xfs_xattr_acl_set(struct dentry dentry, const char name,
431547b3 CH	355	const void *value, size_t size, int flags, int type)
ef14f0c1	356	{
431547b3	357	struct inode *inode = dentry->d_inode;
ef14f0c1	358	struct posix_acl *acl = NULL;
431547b3	359	int error = 0;
ef14f0c1	360
ef14f0c1 CH	361	if (flags & XATTR_CREATE)
	362	return -EINVAL;
	363	if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
	364	return value ? -EACCES : 0;
	365	if ((current_fsuid() != inode->i_uid) && !capable(CAP_FOWNER))
	366	return -EPERM;
	367
	368	if (!value)
	369	goto set_acl;
	370
5f3a4a28	371	acl = posix_acl_from_xattr(&init_user_ns, value, size);
ef14f0c1 CH	372	if (!acl) {
	373	/*
	374	* acl_set_file(3) may request that we set default ACLs with
	375	* zero length -- defend (gracefully) against that here.
	376	*/
	377	goto out;
	378	}
	379	if (IS_ERR(acl)) {
	380	error = PTR_ERR(acl);
	381	goto out;
	382	}
	383
	384	error = posix_acl_valid(acl);
	385	if (error)
	386	goto out_release;
	387
	388	error = -EINVAL;
0a8aa193	389	if (acl->a_count > XFS_ACL_MAX_ENTRIES(XFS_M(inode->i_sb)))
ef14f0c1 CH	390	goto out_release;
	391
	392	if (type == ACL_TYPE_ACCESS) {
d6952123	393	umode_t mode = inode->i_mode;
ef14f0c1 CH	394	error = posix_acl_equiv_mode(acl, &mode);
	395
	396	if (error <= 0) {
	397	posix_acl_release(acl);
	398	acl = NULL;
	399
	400	if (error < 0)
	401	return error;
	402	}
	403
	404	error = xfs_set_mode(inode, mode);
	405	if (error)
	406	goto out_release;
	407	}
	408
	409	set_acl:
	410	error = xfs_set_acl(inode, type, acl);
	411	out_release:
	412	posix_acl_release(acl);
	413	out:
	414	return error;
	415	}
	416
46e58764	417	const struct xattr_handler xfs_xattr_acl_access_handler = {
431547b3 CH	418	.prefix = POSIX_ACL_XATTR_ACCESS,
	419	.flags = ACL_TYPE_ACCESS,
	420	.get = xfs_xattr_acl_get,
	421	.set = xfs_xattr_acl_set,
	422	};
	423
46e58764	424	const struct xattr_handler xfs_xattr_acl_default_handler = {
431547b3 CH	425	.prefix = POSIX_ACL_XATTR_DEFAULT,
	426	.flags = ACL_TYPE_DEFAULT,
	427	.get = xfs_xattr_acl_get,
	428	.set = xfs_xattr_acl_set,
ef14f0c1	429	};