fs/jfs/acl.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *   Copyright (C) International Business Machines  Corp., 2002-2004
   4  *   Copyright (C) Andreas Gruenbacher, 2001
   5  *   Copyright (C) Linus Torvalds, 1991, 1992
   6  */
   7
   8 #include <linux/sched.h>
   9 #include <linux/slab.h>
  10 #include <linux/fs.h>
  11 #include <linux/posix_acl_xattr.h>
  12 #include "jfs_incore.h"
  13 #include "jfs_txnmgr.h"
  14 #include "jfs_xattr.h"
  15 #include "jfs_acl.h"
  16
  17 struct posix_acl *jfs_get_acl(struct inode *inode, int type, bool rcu)
  18 {
  19         struct posix_acl *acl;
  20         char *ea_name;
  21         int size;
  22         char *value = NULL;
  23
  24         if (rcu)
  25                 return ERR_PTR(-ECHILD);
  26
  27         switch(type) {
  28                 case ACL_TYPE_ACCESS:
  29                         ea_name = XATTR_NAME_POSIX_ACL_ACCESS;
  30                         break;
  31                 case ACL_TYPE_DEFAULT:
  32                         ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
  33                         break;
  34                 default:
  35                         return ERR_PTR(-EINVAL);
  36         }
  37
  38         size = __jfs_getxattr(inode, ea_name, NULL, 0);
  39
  40         if (size > 0) {
  41                 value = kmalloc(size, GFP_KERNEL);
  42                 if (!value)
  43                         return ERR_PTR(-ENOMEM);
  44                 size = __jfs_getxattr(inode, ea_name, value, size);
  45         }
  46
  47         if (size < 0) {
  48                 if (size == -ENODATA)
  49                         acl = NULL;
  50                 else
  51                         acl = ERR_PTR(size);
  52         } else {
  53                 acl = posix_acl_from_xattr(&init_user_ns, value, size);
  54         }
  55         kfree(value);
  56         return acl;
  57 }
  58
  59 static int __jfs_set_acl(tid_t tid, struct inode *inode, int type,
  60                        struct posix_acl *acl)
  61 {
  62         char *ea_name;
  63         int rc;
  64         int size = 0;
  65         char *value = NULL;
  66
  67         switch (type) {
  68         case ACL_TYPE_ACCESS:
  69                 ea_name = XATTR_NAME_POSIX_ACL_ACCESS;
  70                 break;
  71         case ACL_TYPE_DEFAULT:
  72                 ea_name = XATTR_NAME_POSIX_ACL_DEFAULT;
  73                 break;
  74         default:
  75                 return -EINVAL;
  76         }
  77
  78         if (acl) {
  79                 size = posix_acl_xattr_size(acl->a_count);
  80                 value = kmalloc(size, GFP_KERNEL);
  81                 if (!value)
  82                         return -ENOMEM;
  83                 rc = posix_acl_to_xattr(&init_user_ns, acl, value, size);
  84                 if (rc < 0)
  85                         goto out;
  86         }
  87         rc = __jfs_setxattr(tid, inode, ea_name, value, size, 0);
  88 out:
  89         kfree(value);
  90
  91         if (!rc)
  92                 set_cached_acl(inode, type, acl);
  93
  94         return rc;
  95 }
  96
  97 int jfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
  98                 struct posix_acl *acl, int type)
  99 {
 100         int rc;
 101         tid_t tid;
 102         int update_mode = 0;
 103         umode_t mode = inode->i_mode;
 104
 105         tid = txBegin(inode->i_sb, 0);
 106         mutex_lock(&JFS_IP(inode)->commit_mutex);
 107         if (type == ACL_TYPE_ACCESS && acl) {
 108                 rc = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
 109                 if (rc)
 110                         goto end_tx;
 111                 if (mode != inode->i_mode)
 112                         update_mode = 1;
 113         }
 114         rc = __jfs_set_acl(tid, inode, type, acl);
 115         if (!rc) {
 116                 if (update_mode) {
 117                         inode->i_mode = mode;
 118                         inode->i_ctime = current_time(inode);
 119                         mark_inode_dirty(inode);
 120                 }
 121                 rc = txCommit(tid, 1, &inode, 0);
 122         }
 123 end_tx:
 124         txEnd(tid);
 125         mutex_unlock(&JFS_IP(inode)->commit_mutex);
 126         return rc;
 127 }
 128
 129 int jfs_init_acl(tid_t tid, struct inode *inode, struct inode *dir)
 130 {
 131         struct posix_acl *default_acl, *acl;
 132         int rc = 0;
 133
 134         rc = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
 135         if (rc)
 136                 return rc;
 137
 138         if (default_acl) {
 139                 rc = __jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, default_acl);
 140                 posix_acl_release(default_acl);
 141         } else {
 142                 inode->i_default_acl = NULL;
 143         }
 144
 145         if (acl) {
 146                 if (!rc)
 147                         rc = __jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, acl);
 148                 posix_acl_release(acl);
 149         } else {
 150                 inode->i_acl = NULL;
 151         }
 152
 153         JFS_IP(inode)->mode2 = (JFS_IP(inode)->mode2 & 0xffff0000) |
 154                                inode->i_mode;
 155
 156         return rc;
 157 }