[linux.git] / fs / ceph / acl.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * linux/fs/ceph/acl.c
 *
 * Copyright (C) 2013 Guangliang Zhao, <[email protected]>
 */

#include <linux/ceph/ceph_debug.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/xattr.h>
#include <linux/posix_acl_xattr.h>
#include <linux/posix_acl.h>
#include <linux/sched.h>
#include <linux/slab.h>

#include "super.h"

static inline void ceph_set_cached_acl(struct inode *inode,
					int type, struct posix_acl *acl)
{
	struct ceph_inode_info *ci = ceph_inode(inode);

	spin_lock(&ci->i_ceph_lock);
	if (__ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 0))
		set_cached_acl(inode, type, acl);
	else
		forget_cached_acl(inode, type);
	spin_unlock(&ci->i_ceph_lock);
}

struct posix_acl *ceph_get_acl(struct inode *inode, int type, bool rcu)
{
	int size;
	unsigned int retry_cnt = 0;
	const char *name;
	char *value = NULL;
	struct posix_acl *acl;

	if (rcu)
		return ERR_PTR(-ECHILD);

	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();
	}

retry:
	size = __ceph_getxattr(inode, name, "", 0);
	if (size > 0) {
		value = kzalloc(size, GFP_NOFS);
		if (!value)
			return ERR_PTR(-ENOMEM);
		size = __ceph_getxattr(inode, name, value, size);
	}

	if (size == -ERANGE && retry_cnt < 10) {
		retry_cnt++;
		kfree(value);
		value = NULL;
		goto retry;
	}

	if (size > 0) {
		acl = posix_acl_from_xattr(&init_user_ns, value, size);
	} else if (size == -ENODATA || size == 0) {
		acl = NULL;
	} else {
		pr_err_ratelimited("get acl %llx.%llx failed, err=%d\n",
				   ceph_vinop(inode), size);
		acl = ERR_PTR(-EIO);
	}

	kfree(value);

	if (!IS_ERR(acl))
		ceph_set_cached_acl(inode, type, acl);

	return acl;
}

int ceph_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
		 struct posix_acl *acl, int type)
{
	int ret = 0, size = 0;
	const char *name = NULL;
	char *value = NULL;
	struct iattr newattrs;
	struct timespec64 old_ctime = inode->i_ctime;
	umode_t new_mode = inode->i_mode, old_mode = inode->i_mode;

	if (ceph_snap(inode) != CEPH_NOSNAP) {
		ret = -EROFS;
		goto out;
	}

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = XATTR_NAME_POSIX_ACL_ACCESS;
		if (acl) {
			ret = posix_acl_update_mode(&init_user_ns, inode,
						    &new_mode, &acl);
			if (ret)
				goto out;
		}
		break;
	case ACL_TYPE_DEFAULT:
		if (!S_ISDIR(inode->i_mode)) {
			ret = acl ? -EINVAL : 0;
			goto out;
		}
		name = XATTR_NAME_POSIX_ACL_DEFAULT;
		break;
	default:
		ret = -EINVAL;
		goto out;
	}

	if (acl) {
		size = posix_acl_xattr_size(acl->a_count);
		value = kmalloc(size, GFP_NOFS);
		if (!value) {
			ret = -ENOMEM;
			goto out;
		}

		ret = posix_acl_to_xattr(&init_user_ns, acl, value, size);
		if (ret < 0)
			goto out_free;
	}

	if (new_mode != old_mode) {
		newattrs.ia_ctime = current_time(inode);
		newattrs.ia_mode = new_mode;
		newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
		ret = __ceph_setattr(inode, &newattrs);
		if (ret)
			goto out_free;
	}

	ret = __ceph_setxattr(inode, name, value, size, 0);
	if (ret) {
		if (new_mode != old_mode) {
			newattrs.ia_ctime = old_ctime;
			newattrs.ia_mode = old_mode;
			newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
			__ceph_setattr(inode, &newattrs);
		}
		goto out_free;
	}

	ceph_set_cached_acl(inode, type, acl);

out_free:
	kfree(value);
out:
	return ret;
}

int ceph_pre_init_acls(struct inode *dir, umode_t *mode,
		       struct ceph_acl_sec_ctx *as_ctx)
{
	struct posix_acl *acl, *default_acl;
	size_t val_size1 = 0, val_size2 = 0;
	struct ceph_pagelist *pagelist = NULL;
	void *tmp_buf = NULL;
	int err;

	err = posix_acl_create(dir, mode, &default_acl, &acl);
	if (err)
		return err;

	if (acl) {
		err = posix_acl_equiv_mode(acl, mode);
		if (err < 0)
			goto out_err;
		if (err == 0) {
			posix_acl_release(acl);
			acl = NULL;
		}
	}

	if (!default_acl && !acl)
		return 0;

	if (acl)
		val_size1 = posix_acl_xattr_size(acl->a_count);
	if (default_acl)
		val_size2 = posix_acl_xattr_size(default_acl->a_count);

	err = -ENOMEM;
	tmp_buf = kmalloc(max(val_size1, val_size2), GFP_KERNEL);
	if (!tmp_buf)
		goto out_err;
	pagelist = ceph_pagelist_alloc(GFP_KERNEL);
	if (!pagelist)
		goto out_err;

	err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
	if (err)
		goto out_err;

	ceph_pagelist_encode_32(pagelist, acl && default_acl ? 2 : 1);

	if (acl) {
		size_t len = strlen(XATTR_NAME_POSIX_ACL_ACCESS);
		err = ceph_pagelist_reserve(pagelist, len + val_size1 + 8);
		if (err)
			goto out_err;
		ceph_pagelist_encode_string(pagelist, XATTR_NAME_POSIX_ACL_ACCESS,
					    len);
		err = posix_acl_to_xattr(&init_user_ns, acl,
					 tmp_buf, val_size1);
		if (err < 0)
			goto out_err;
		ceph_pagelist_encode_32(pagelist, val_size1);
		ceph_pagelist_append(pagelist, tmp_buf, val_size1);
	}
	if (default_acl) {
		size_t len = strlen(XATTR_NAME_POSIX_ACL_DEFAULT);
		err = ceph_pagelist_reserve(pagelist, len + val_size2 + 8);
		if (err)
			goto out_err;
		ceph_pagelist_encode_string(pagelist,
					  XATTR_NAME_POSIX_ACL_DEFAULT, len);
		err = posix_acl_to_xattr(&init_user_ns, default_acl,
					 tmp_buf, val_size2);
		if (err < 0)
			goto out_err;
		ceph_pagelist_encode_32(pagelist, val_size2);
		ceph_pagelist_append(pagelist, tmp_buf, val_size2);
	}

	kfree(tmp_buf);

	as_ctx->acl = acl;
	as_ctx->default_acl = default_acl;
	as_ctx->pagelist = pagelist;
	return 0;

out_err:
	posix_acl_release(acl);
	posix_acl_release(default_acl);
	kfree(tmp_buf);
	if (pagelist)
		ceph_pagelist_release(pagelist);
	return err;
}

void ceph_init_inode_acls(struct inode *inode, struct ceph_acl_sec_ctx *as_ctx)
{
	if (!inode)
		return;
	ceph_set_cached_acl(inode, ACL_TYPE_ACCESS, as_ctx->acl);
	ceph_set_cached_acl(inode, ACL_TYPE_DEFAULT, as_ctx->default_acl);
}
Commit	Line	Data
f2cde895	1	// SPDX-License-Identifier: GPL-2.0-only
7221fe4c GZ	2	/*
	3	* linux/fs/ceph/acl.c
	4	*
	5	* Copyright (C) 2013 Guangliang Zhao, <[email protected]>
7221fe4c GZ	6	*/
	7
	8	#include <linux/ceph/ceph_debug.h>
	9	#include <linux/fs.h>
	10	#include <linux/string.h>
	11	#include <linux/xattr.h>
	12	#include <linux/posix_acl_xattr.h>
	13	#include <linux/posix_acl.h>
	14	#include <linux/sched.h>
	15	#include <linux/slab.h>
	16
	17	#include "super.h"
	18
	19	static inline void ceph_set_cached_acl(struct inode *inode,
	20	int type, struct posix_acl *acl)
	21	{
	22	struct ceph_inode_info *ci = ceph_inode(inode);
	23
	24	spin_lock(&ci->i_ceph_lock);
1af16d54	25	if (__ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 0))
7221fe4c	26	set_cached_acl(inode, type, acl);
b8a7a3a6 AG	27	else
b8a7a3a6 AG	28	forget_cached_acl(inode, type);
7221fe4c GZ	29	spin_unlock(&ci->i_ceph_lock);
	30	}
	31
0cad6246	32	struct posix_acl ceph_get_acl(struct inode inode, int type, bool rcu)
7221fe4c GZ	33	{
7221fe4c GZ	34	int size;
f017754d	35	unsigned int retry_cnt = 0;
7221fe4c GZ	36	const char *name;
	37	char *value = NULL;
	38	struct posix_acl *acl;
	39
0cad6246 MS	40	if (rcu)
	41	return ERR_PTR(-ECHILD);
	42
7221fe4c GZ	43	switch (type) {
7221fe4c GZ	44	case ACL_TYPE_ACCESS:
97d79299	45	name = XATTR_NAME_POSIX_ACL_ACCESS;
7221fe4c GZ	46	break;
7221fe4c GZ	47	case ACL_TYPE_DEFAULT:
97d79299	48	name = XATTR_NAME_POSIX_ACL_DEFAULT;
7221fe4c GZ	49	break;
	50	default:
	51	BUG();
	52	}
	53
f017754d	54	retry:
7221fe4c GZ	55	size = __ceph_getxattr(inode, name, "", 0);
	56	if (size > 0) {
	57	value = kzalloc(size, GFP_NOFS);
	58	if (!value)
	59	return ERR_PTR(-ENOMEM);
	60	size = __ceph_getxattr(inode, name, value, size);
	61	}
	62
f017754d CX	63	if (size == -ERANGE && retry_cnt < 10) {
	64	retry_cnt++;
	65	kfree(value);
	66	value = NULL;
	67	goto retry;
	68	}
	69
	70	if (size > 0) {
7221fe4c	71	acl = posix_acl_from_xattr(&init_user_ns, value, size);
f017754d	72	} else if (size == -ENODATA \|\| size == 0) {
7221fe4c	73	acl = NULL;
f017754d CX	74	} else {
	75	pr_err_ratelimited("get acl %llx.%llx failed, err=%d\n",
	76	ceph_vinop(inode), size);
7221fe4c	77	acl = ERR_PTR(-EIO);
f017754d	78	}
7221fe4c GZ	79
	80	kfree(value);
	81
	82	if (!IS_ERR(acl))
	83	ceph_set_cached_acl(inode, type, acl);
	84
	85	return acl;
	86	}
	87
549c7297 CB	88	int ceph_set_acl(struct user_namespace mnt_userns, struct inode inode,
549c7297 CB	89	struct posix_acl *acl, int type)
7221fe4c GZ	90	{
	91	int ret = 0, size = 0;
	92	const char *name = NULL;
	93	char *value = NULL;
	94	struct iattr newattrs;
93d35c75	95	struct timespec64 old_ctime = inode->i_ctime;
7221fe4c GZ	96	umode_t new_mode = inode->i_mode, old_mode = inode->i_mode;
7221fe4c GZ	97
5da20799 CX	98	if (ceph_snap(inode) != CEPH_NOSNAP) {
	99	ret = -EROFS;
	100	goto out;
	101	}
	102
7221fe4c GZ	103	switch (type) {
7221fe4c GZ	104	case ACL_TYPE_ACCESS:
97d79299	105	name = XATTR_NAME_POSIX_ACL_ACCESS;
7221fe4c	106	if (acl) {
e65ce2a5 CB	107	ret = posix_acl_update_mode(&init_user_ns, inode,
e65ce2a5 CB	108	&new_mode, &acl);
07393101	109	if (ret)
7221fe4c	110	goto out;
7221fe4c GZ	111	}
	112	break;
	113	case ACL_TYPE_DEFAULT:
	114	if (!S_ISDIR(inode->i_mode)) {
	115	ret = acl ? -EINVAL : 0;
	116	goto out;
	117	}
97d79299	118	name = XATTR_NAME_POSIX_ACL_DEFAULT;
7221fe4c GZ	119	break;
	120	default:
	121	ret = -EINVAL;
	122	goto out;
	123	}
	124
	125	if (acl) {
	126	size = posix_acl_xattr_size(acl->a_count);
	127	value = kmalloc(size, GFP_NOFS);
	128	if (!value) {
	129	ret = -ENOMEM;
	130	goto out;
	131	}
	132
	133	ret = posix_acl_to_xattr(&init_user_ns, acl, value, size);
	134	if (ret < 0)
	135	goto out_free;
	136	}
	137
	138	if (new_mode != old_mode) {
4ca2fea6	139	newattrs.ia_ctime = current_time(inode);
7221fe4c	140	newattrs.ia_mode = new_mode;
93d35c75	141	newattrs.ia_valid = ATTR_MODE \| ATTR_CTIME;
a26fecca	142	ret = __ceph_setattr(inode, &newattrs);
7221fe4c	143	if (ret)
a26fecca	144	goto out_free;
7221fe4c GZ	145	}
7221fe4c GZ	146
a26fecca	147	ret = __ceph_setxattr(inode, name, value, size, 0);
7221fe4c GZ	148	if (ret) {
7221fe4c GZ	149	if (new_mode != old_mode) {
93d35c75	150	newattrs.ia_ctime = old_ctime;
7221fe4c	151	newattrs.ia_mode = old_mode;
93d35c75	152	newattrs.ia_valid = ATTR_MODE \| ATTR_CTIME;
a26fecca	153	__ceph_setattr(inode, &newattrs);
7221fe4c	154	}
a26fecca	155	goto out_free;
7221fe4c GZ	156	}
	157
	158	ceph_set_cached_acl(inode, type, acl);
	159
	160	out_free:
	161	kfree(value);
	162	out:
	163	return ret;
	164	}
	165
b1ee94aa	166	int ceph_pre_init_acls(struct inode dir, umode_t mode,
5c31e92d	167	struct ceph_acl_sec_ctx *as_ctx)
7221fe4c	168	{
b1ee94aa YZ	169	struct posix_acl acl, default_acl;
	170	size_t val_size1 = 0, val_size2 = 0;
	171	struct ceph_pagelist *pagelist = NULL;
	172	void *tmp_buf = NULL;
	173	int err;
	174
	175	err = posix_acl_create(dir, mode, &default_acl, &acl);
	176	if (err)
	177	return err;
	178
	179	if (acl) {
61ad36d4 CX	180	err = posix_acl_equiv_mode(acl, mode);
61ad36d4 CX	181	if (err < 0)
b1ee94aa	182	goto out_err;
61ad36d4	183	if (err == 0) {
b1ee94aa YZ	184	posix_acl_release(acl);
b1ee94aa YZ	185	acl = NULL;
f5f18647	186	}
f5f18647	187	}
7221fe4c	188
b1ee94aa YZ	189	if (!default_acl && !acl)
	190	return 0;
	191
	192	if (acl)
	193	val_size1 = posix_acl_xattr_size(acl->a_count);
	194	if (default_acl)
	195	val_size2 = posix_acl_xattr_size(default_acl->a_count);
	196
	197	err = -ENOMEM;
687265e5	198	tmp_buf = kmalloc(max(val_size1, val_size2), GFP_KERNEL);
b1ee94aa YZ	199	if (!tmp_buf)
b1ee94aa YZ	200	goto out_err;
33165d47	201	pagelist = ceph_pagelist_alloc(GFP_KERNEL);
b1ee94aa YZ	202	if (!pagelist)
b1ee94aa YZ	203	goto out_err;
b1ee94aa YZ	204
	205	err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
	206	if (err)
	207	goto out_err;
	208
	209	ceph_pagelist_encode_32(pagelist, acl && default_acl ? 2 : 1);
	210
75858236	211	if (acl) {
97d79299	212	size_t len = strlen(XATTR_NAME_POSIX_ACL_ACCESS);
b1ee94aa YZ	213	err = ceph_pagelist_reserve(pagelist, len + val_size1 + 8);
	214	if (err)
	215	goto out_err;
97d79299	216	ceph_pagelist_encode_string(pagelist, XATTR_NAME_POSIX_ACL_ACCESS,
b1ee94aa YZ	217	len);
	218	err = posix_acl_to_xattr(&init_user_ns, acl,
	219	tmp_buf, val_size1);
	220	if (err < 0)
	221	goto out_err;
	222	ceph_pagelist_encode_32(pagelist, val_size1);
	223	ceph_pagelist_append(pagelist, tmp_buf, val_size1);
75858236	224	}
b1ee94aa	225	if (default_acl) {
97d79299	226	size_t len = strlen(XATTR_NAME_POSIX_ACL_DEFAULT);
b1ee94aa YZ	227	err = ceph_pagelist_reserve(pagelist, len + val_size2 + 8);
	228	if (err)
	229	goto out_err;
d80865bf CX	230	ceph_pagelist_encode_string(pagelist,
d80865bf CX	231	XATTR_NAME_POSIX_ACL_DEFAULT, len);
b1ee94aa YZ	232	err = posix_acl_to_xattr(&init_user_ns, default_acl,
	233	tmp_buf, val_size2);
	234	if (err < 0)
	235	goto out_err;
	236	ceph_pagelist_encode_32(pagelist, val_size2);
	237	ceph_pagelist_append(pagelist, tmp_buf, val_size2);
	238	}
	239
	240	kfree(tmp_buf);
	241
5c31e92d YZ	242	as_ctx->acl = acl;
	243	as_ctx->default_acl = default_acl;
	244	as_ctx->pagelist = pagelist;
b1ee94aa YZ	245	return 0;
	246
	247	out_err:
	248	posix_acl_release(acl);
	249	posix_acl_release(default_acl);
	250	kfree(tmp_buf);
	251	if (pagelist)
	252	ceph_pagelist_release(pagelist);
	253	return err;
	254	}
	255
5c31e92d	256	void ceph_init_inode_acls(struct inode inode, struct ceph_acl_sec_ctx as_ctx)
b1ee94aa YZ	257	{
	258	if (!inode)
	259	return;
5c31e92d YZ	260	ceph_set_cached_acl(inode, ACL_TYPE_ACCESS, as_ctx->acl);
5c31e92d YZ	261	ceph_set_cached_acl(inode, ACL_TYPE_DEFAULT, as_ctx->default_acl);
7221fe4c	262	}