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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * linux/fs/ceph/acl.c4 *5 * Copyright (C) 2013 Guangliang Zhao, <lucienchao@gmail.com>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#include "mds_client.h"19 20static 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);26 if (__ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 0))27 set_cached_acl(inode, type, acl);28 else29 forget_cached_acl(inode, type);30 spin_unlock(&ci->i_ceph_lock);31}32 33struct posix_acl *ceph_get_acl(struct inode *inode, int type, bool rcu)34{35 struct ceph_client *cl = ceph_inode_to_client(inode);36 int size;37 unsigned int retry_cnt = 0;38 const char *name;39 char *value = NULL;40 struct posix_acl *acl;41 42 if (rcu)43 return ERR_PTR(-ECHILD);44 45 switch (type) {46 case ACL_TYPE_ACCESS:47 name = XATTR_NAME_POSIX_ACL_ACCESS;48 break;49 case ACL_TYPE_DEFAULT:50 name = XATTR_NAME_POSIX_ACL_DEFAULT;51 break;52 default:53 BUG();54 }55 56retry: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 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) {73 acl = posix_acl_from_xattr(&init_user_ns, value, size);74 } else if (size == -ENODATA || size == 0) {75 acl = NULL;76 } else {77 pr_err_ratelimited_client(cl, "%llx.%llx failed, err=%d\n",78 ceph_vinop(inode), size);79 acl = ERR_PTR(-EIO);80 }81 82 kfree(value);83 84 if (!IS_ERR(acl))85 ceph_set_cached_acl(inode, type, acl);86 87 return acl;88}89 90int ceph_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,91 struct posix_acl *acl, int type)92{93 int ret = 0, size = 0;94 const char *name = NULL;95 char *value = NULL;96 struct iattr newattrs;97 struct inode *inode = d_inode(dentry);98 struct timespec64 old_ctime = inode_get_ctime(inode);99 umode_t new_mode = inode->i_mode, old_mode = inode->i_mode;100 101 if (ceph_snap(inode) != CEPH_NOSNAP) {102 ret = -EROFS;103 goto out;104 }105 106 switch (type) {107 case ACL_TYPE_ACCESS:108 name = XATTR_NAME_POSIX_ACL_ACCESS;109 if (acl) {110 ret = posix_acl_update_mode(idmap, inode,111 &new_mode, &acl);112 if (ret)113 goto out;114 }115 break;116 case ACL_TYPE_DEFAULT:117 if (!S_ISDIR(inode->i_mode)) {118 ret = acl ? -EINVAL : 0;119 goto out;120 }121 name = XATTR_NAME_POSIX_ACL_DEFAULT;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) {142 newattrs.ia_ctime = current_time(inode);143 newattrs.ia_mode = new_mode;144 newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;145 ret = __ceph_setattr(idmap, inode, &newattrs, NULL);146 if (ret)147 goto out_free;148 }149 150 ret = __ceph_setxattr(inode, name, value, size, 0);151 if (ret) {152 if (new_mode != old_mode) {153 newattrs.ia_ctime = old_ctime;154 newattrs.ia_mode = old_mode;155 newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;156 __ceph_setattr(idmap, inode, &newattrs, NULL);157 }158 goto out_free;159 }160 161 ceph_set_cached_acl(inode, type, acl);162 163out_free:164 kfree(value);165out:166 return ret;167}168 169int ceph_pre_init_acls(struct inode *dir, umode_t *mode,170 struct ceph_acl_sec_ctx *as_ctx)171{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) {183 err = posix_acl_equiv_mode(acl, mode);184 if (err < 0)185 goto out_err;186 if (err == 0) {187 posix_acl_release(acl);188 acl = NULL;189 }190 }191 192 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;201 tmp_buf = kmalloc(max(val_size1, val_size2), GFP_KERNEL);202 if (!tmp_buf)203 goto out_err;204 pagelist = ceph_pagelist_alloc(GFP_KERNEL);205 if (!pagelist)206 goto out_err;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);213 214 if (acl) {215 size_t len = strlen(XATTR_NAME_POSIX_ACL_ACCESS);216 err = ceph_pagelist_reserve(pagelist, len + val_size1 + 8);217 if (err)218 goto out_err;219 ceph_pagelist_encode_string(pagelist, XATTR_NAME_POSIX_ACL_ACCESS,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);227 }228 if (default_acl) {229 size_t len = strlen(XATTR_NAME_POSIX_ACL_DEFAULT);230 err = ceph_pagelist_reserve(pagelist, len + val_size2 + 8);231 if (err)232 goto out_err;233 ceph_pagelist_encode_string(pagelist,234 XATTR_NAME_POSIX_ACL_DEFAULT, len);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);244 245 as_ctx->acl = acl;246 as_ctx->default_acl = default_acl;247 as_ctx->pagelist = pagelist;248 return 0;249 250out_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 259void ceph_init_inode_acls(struct inode *inode, struct ceph_acl_sec_ctx *as_ctx)260{261 if (!inode)262 return;263 ceph_set_cached_acl(inode, ACL_TYPE_ACCESS, as_ctx->acl);264 ceph_set_cached_acl(inode, ACL_TYPE_DEFAULT, as_ctx->default_acl);265}266