[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"
#include "mds_client.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)
{
	struct ceph_client *cl = ceph_inode_to_client(inode);
	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_client(cl, "%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 mnt_idmap *idmap, struct dentry *dentry,
		 struct posix_acl *acl, int type)
{
	int ret = 0, size = 0;
	const char *name = NULL;
	char *value = NULL;
	struct iattr newattrs;
	struct inode *inode = d_inode(dentry);
	struct timespec64 old_ctime = inode_get_ctime(inode);
	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(idmap, 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(idmap, inode, &newattrs, NULL);
		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(idmap, inode, &newattrs, NULL);
		}
		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"
38d46409	18	#include "mds_client.h"
7221fe4c GZ	19
	20	static inline void ceph_set_cached_acl(struct inode *inode,
	21	int type, struct posix_acl *acl)
	22	{
	23	struct ceph_inode_info *ci = ceph_inode(inode);
	24
	25	spin_lock(&ci->i_ceph_lock);
1af16d54	26	if (__ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 0))
7221fe4c	27	set_cached_acl(inode, type, acl);
b8a7a3a6 AG	28	else
b8a7a3a6 AG	29	forget_cached_acl(inode, type);
7221fe4c GZ	30	spin_unlock(&ci->i_ceph_lock);
	31	}
	32
0cad6246	33	struct posix_acl ceph_get_acl(struct inode inode, int type, bool rcu)
7221fe4c	34	{
38d46409	35	struct ceph_client *cl = ceph_inode_to_client(inode);
7221fe4c	36	int size;
f017754d	37	unsigned int retry_cnt = 0;
7221fe4c GZ	38	const char *name;
	39	char *value = NULL;
	40	struct posix_acl *acl;
	41
0cad6246 MS	42	if (rcu)
	43	return ERR_PTR(-ECHILD);
	44
7221fe4c GZ	45	switch (type) {
7221fe4c GZ	46	case ACL_TYPE_ACCESS:
97d79299	47	name = XATTR_NAME_POSIX_ACL_ACCESS;
7221fe4c GZ	48	break;
7221fe4c GZ	49	case ACL_TYPE_DEFAULT:
97d79299	50	name = XATTR_NAME_POSIX_ACL_DEFAULT;
7221fe4c GZ	51	break;
	52	default:
	53	BUG();
	54	}
	55
f017754d	56	retry:
7221fe4c GZ	57	size = __ceph_getxattr(inode, name, "", 0);
	58	if (size > 0) {
	59	value = kzalloc(size, GFP_NOFS);
	60	if (!value)
	61	return ERR_PTR(-ENOMEM);
	62	size = __ceph_getxattr(inode, name, value, size);
	63	}
	64
f017754d CX	65	if (size == -ERANGE && retry_cnt < 10) {
	66	retry_cnt++;
	67	kfree(value);
	68	value = NULL;
	69	goto retry;
	70	}
	71
	72	if (size > 0) {
7221fe4c	73	acl = posix_acl_from_xattr(&init_user_ns, value, size);
f017754d	74	} else if (size == -ENODATA \|\| size == 0) {
7221fe4c	75	acl = NULL;
f017754d	76	} else {
38d46409 XL	77	pr_err_ratelimited_client(cl, "%llx.%llx failed, err=%d\n",
38d46409 XL	78	ceph_vinop(inode), size);
7221fe4c	79	acl = ERR_PTR(-EIO);
f017754d	80	}
7221fe4c GZ	81
	82	kfree(value);
	83
	84	if (!IS_ERR(acl))
	85	ceph_set_cached_acl(inode, type, acl);
	86
	87	return acl;
	88	}
	89
13e83a49	90	int ceph_set_acl(struct mnt_idmap idmap, struct dentry dentry,
549c7297	91	struct posix_acl *acl, int type)
7221fe4c GZ	92	{
	93	int ret = 0, size = 0;
	94	const char *name = NULL;
	95	char *value = NULL;
	96	struct iattr newattrs;
138060ba	97	struct inode *inode = d_inode(dentry);
7795aef0	98	struct timespec64 old_ctime = inode_get_ctime(inode);
7221fe4c GZ	99	umode_t new_mode = inode->i_mode, old_mode = inode->i_mode;
7221fe4c GZ	100
5da20799 CX	101	if (ceph_snap(inode) != CEPH_NOSNAP) {
	102	ret = -EROFS;
	103	goto out;
	104	}
	105
7221fe4c GZ	106	switch (type) {
7221fe4c GZ	107	case ACL_TYPE_ACCESS:
97d79299	108	name = XATTR_NAME_POSIX_ACL_ACCESS;
7221fe4c	109	if (acl) {
2cce72dd	110	ret = posix_acl_update_mode(idmap, inode,
e65ce2a5	111	&new_mode, &acl);
07393101	112	if (ret)
7221fe4c	113	goto out;
7221fe4c GZ	114	}
	115	break;
	116	case ACL_TYPE_DEFAULT:
	117	if (!S_ISDIR(inode->i_mode)) {
	118	ret = acl ? -EINVAL : 0;
	119	goto out;
	120	}
97d79299	121	name = XATTR_NAME_POSIX_ACL_DEFAULT;
7221fe4c GZ	122	break;
	123	default:
	124	ret = -EINVAL;
	125	goto out;
	126	}
	127
	128	if (acl) {
	129	size = posix_acl_xattr_size(acl->a_count);
	130	value = kmalloc(size, GFP_NOFS);
	131	if (!value) {
	132	ret = -ENOMEM;
	133	goto out;
	134	}
	135
	136	ret = posix_acl_to_xattr(&init_user_ns, acl, value, size);
	137	if (ret < 0)
	138	goto out_free;
	139	}
	140
	141	if (new_mode != old_mode) {
4ca2fea6	142	newattrs.ia_ctime = current_time(inode);
7221fe4c	143	newattrs.ia_mode = new_mode;
93d35c75	144	newattrs.ia_valid = ATTR_MODE \| ATTR_CTIME;
79c66a0c	145	ret = __ceph_setattr(idmap, inode, &newattrs, NULL);
7221fe4c	146	if (ret)
a26fecca	147	goto out_free;
7221fe4c GZ	148	}
7221fe4c GZ	149
a26fecca	150	ret = __ceph_setxattr(inode, name, value, size, 0);
7221fe4c GZ	151	if (ret) {
7221fe4c GZ	152	if (new_mode != old_mode) {
93d35c75	153	newattrs.ia_ctime = old_ctime;
7221fe4c	154	newattrs.ia_mode = old_mode;
93d35c75	155	newattrs.ia_valid = ATTR_MODE \| ATTR_CTIME;
79c66a0c	156	__ceph_setattr(idmap, inode, &newattrs, NULL);
7221fe4c	157	}
a26fecca	158	goto out_free;
7221fe4c GZ	159	}
	160
	161	ceph_set_cached_acl(inode, type, acl);
	162
	163	out_free:
	164	kfree(value);
	165	out:
	166	return ret;
	167	}
	168
b1ee94aa	169	int ceph_pre_init_acls(struct inode dir, umode_t mode,
5c31e92d	170	struct ceph_acl_sec_ctx *as_ctx)
7221fe4c	171	{
b1ee94aa YZ	172	struct posix_acl acl, default_acl;
	173	size_t val_size1 = 0, val_size2 = 0;
	174	struct ceph_pagelist *pagelist = NULL;
	175	void *tmp_buf = NULL;
	176	int err;
	177
	178	err = posix_acl_create(dir, mode, &default_acl, &acl);
	179	if (err)
	180	return err;
	181
	182	if (acl) {
61ad36d4 CX	183	err = posix_acl_equiv_mode(acl, mode);
61ad36d4 CX	184	if (err < 0)
b1ee94aa	185	goto out_err;
61ad36d4	186	if (err == 0) {
b1ee94aa YZ	187	posix_acl_release(acl);
b1ee94aa YZ	188	acl = NULL;
f5f18647	189	}
f5f18647	190	}
7221fe4c	191
b1ee94aa YZ	192	if (!default_acl && !acl)
	193	return 0;
	194
	195	if (acl)
	196	val_size1 = posix_acl_xattr_size(acl->a_count);
	197	if (default_acl)
	198	val_size2 = posix_acl_xattr_size(default_acl->a_count);
	199
	200	err = -ENOMEM;
687265e5	201	tmp_buf = kmalloc(max(val_size1, val_size2), GFP_KERNEL);
b1ee94aa YZ	202	if (!tmp_buf)
b1ee94aa YZ	203	goto out_err;
33165d47	204	pagelist = ceph_pagelist_alloc(GFP_KERNEL);
b1ee94aa YZ	205	if (!pagelist)
b1ee94aa YZ	206	goto out_err;
b1ee94aa YZ	207
	208	err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
	209	if (err)
	210	goto out_err;
	211
	212	ceph_pagelist_encode_32(pagelist, acl && default_acl ? 2 : 1);
	213
75858236	214	if (acl) {
97d79299	215	size_t len = strlen(XATTR_NAME_POSIX_ACL_ACCESS);
b1ee94aa YZ	216	err = ceph_pagelist_reserve(pagelist, len + val_size1 + 8);
	217	if (err)
	218	goto out_err;
97d79299	219	ceph_pagelist_encode_string(pagelist, XATTR_NAME_POSIX_ACL_ACCESS,
b1ee94aa YZ	220	len);
	221	err = posix_acl_to_xattr(&init_user_ns, acl,
	222	tmp_buf, val_size1);
	223	if (err < 0)
	224	goto out_err;
	225	ceph_pagelist_encode_32(pagelist, val_size1);
	226	ceph_pagelist_append(pagelist, tmp_buf, val_size1);
75858236	227	}
b1ee94aa	228	if (default_acl) {
97d79299	229	size_t len = strlen(XATTR_NAME_POSIX_ACL_DEFAULT);
b1ee94aa YZ	230	err = ceph_pagelist_reserve(pagelist, len + val_size2 + 8);
	231	if (err)
	232	goto out_err;
d80865bf CX	233	ceph_pagelist_encode_string(pagelist,
d80865bf CX	234	XATTR_NAME_POSIX_ACL_DEFAULT, len);
b1ee94aa YZ	235	err = posix_acl_to_xattr(&init_user_ns, default_acl,
	236	tmp_buf, val_size2);
	237	if (err < 0)
	238	goto out_err;
	239	ceph_pagelist_encode_32(pagelist, val_size2);
	240	ceph_pagelist_append(pagelist, tmp_buf, val_size2);
	241	}
	242
	243	kfree(tmp_buf);
	244
5c31e92d YZ	245	as_ctx->acl = acl;
	246	as_ctx->default_acl = default_acl;
	247	as_ctx->pagelist = pagelist;
b1ee94aa YZ	248	return 0;
	249
	250	out_err:
	251	posix_acl_release(acl);
	252	posix_acl_release(default_acl);
	253	kfree(tmp_buf);
	254	if (pagelist)
	255	ceph_pagelist_release(pagelist);
	256	return err;
	257	}
	258
5c31e92d	259	void ceph_init_inode_acls(struct inode inode, struct ceph_acl_sec_ctx as_ctx)
b1ee94aa YZ	260	{
	261	if (!inode)
	262	return;
5c31e92d YZ	263	ceph_set_cached_acl(inode, ACL_TYPE_ACCESS, as_ctx->acl);
5c31e92d YZ	264	ceph_set_cached_acl(inode, ACL_TYPE_DEFAULT, as_ctx->default_acl);
7221fe4c	265	}