1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
4 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
5 */
6
7 #include <linux/sched.h>
8 #include <linux/slab.h>
9 #include <linux/spinlock.h>
10 #include <linux/completion.h>
11 #include <linux/buffer_head.h>
12 #include <linux/xattr.h>
13 #include <linux/posix_acl.h>
14 #include <linux/posix_acl_xattr.h>
15 #include <linux/gfs2_ondisk.h>
16
17 #include "gfs2.h"
18 #include "incore.h"
19 #include "acl.h"
20 #include "xattr.h"
21 #include "glock.h"
22 #include "inode.h"
23 #include "meta_io.h"
24 #include "quota.h"
25 #include "rgrp.h"
26 #include "trans.h"
27 #include "util.h"
28
gfs2_acl_name(int type)29 static const char *gfs2_acl_name(int type)
30 {
31 switch (type) {
32 case ACL_TYPE_ACCESS:
33 return XATTR_POSIX_ACL_ACCESS;
34 case ACL_TYPE_DEFAULT:
35 return XATTR_POSIX_ACL_DEFAULT;
36 }
37 return NULL;
38 }
39
__gfs2_get_acl(struct inode * inode,int type)40 static struct posix_acl *__gfs2_get_acl(struct inode *inode, int type)
41 {
42 struct gfs2_inode *ip = GFS2_I(inode);
43 struct posix_acl *acl;
44 const char *name;
45 char *data;
46 int len;
47
48 if (!ip->i_eattr)
49 return NULL;
50
51 name = gfs2_acl_name(type);
52 len = gfs2_xattr_acl_get(ip, name, &data);
53 if (len <= 0)
54 return ERR_PTR(len);
55 acl = posix_acl_from_xattr(&init_user_ns, data, len);
56 kfree(data);
57 return acl;
58 }
59
gfs2_get_acl(struct inode * inode,int type)60 struct posix_acl *gfs2_get_acl(struct inode *inode, int type)
61 {
62 struct gfs2_inode *ip = GFS2_I(inode);
63 struct gfs2_holder gh;
64 bool need_unlock = false;
65 struct posix_acl *acl;
66
67 if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
68 int ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
69 LM_FLAG_ANY, &gh);
70 if (ret)
71 return ERR_PTR(ret);
72 need_unlock = true;
73 }
74 acl = __gfs2_get_acl(inode, type);
75 if (need_unlock)
76 gfs2_glock_dq_uninit(&gh);
77 return acl;
78 }
79
__gfs2_set_acl(struct inode * inode,struct posix_acl * acl,int type)80 int __gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
81 {
82 int error;
83 size_t len;
84 char *data;
85 const char *name = gfs2_acl_name(type);
86
87 if (acl) {
88 len = posix_acl_xattr_size(acl->a_count);
89 data = kmalloc(len, GFP_NOFS);
90 if (data == NULL)
91 return -ENOMEM;
92 error = posix_acl_to_xattr(&init_user_ns, acl, data, len);
93 if (error < 0)
94 goto out;
95 } else {
96 data = NULL;
97 len = 0;
98 }
99
100 error = __gfs2_xattr_set(inode, name, data, len, 0, GFS2_EATYPE_SYS);
101 if (error)
102 goto out;
103 set_cached_acl(inode, type, acl);
104 out:
105 kfree(data);
106 return error;
107 }
108
gfs2_set_acl(struct inode * inode,struct posix_acl * acl,int type)109 int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
110 {
111 struct gfs2_inode *ip = GFS2_I(inode);
112 struct gfs2_holder gh;
113 bool need_unlock = false;
114 int ret;
115 umode_t mode;
116
117 if (acl && acl->a_count > GFS2_ACL_MAX_ENTRIES(GFS2_SB(inode)))
118 return -E2BIG;
119
120 ret = gfs2_qa_get(ip);
121 if (ret)
122 return ret;
123
124 if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
125 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
126 if (ret)
127 goto out;
128 need_unlock = true;
129 }
130
131 mode = inode->i_mode;
132 if (type == ACL_TYPE_ACCESS && acl) {
133 ret = posix_acl_update_mode(inode, &mode, &acl);
134 if (ret)
135 goto unlock;
136 }
137
138 ret = __gfs2_set_acl(inode, acl, type);
139 if (!ret && mode != inode->i_mode) {
140 inode->i_ctime = current_time(inode);
141 inode->i_mode = mode;
142 mark_inode_dirty(inode);
143 }
144 unlock:
145 if (need_unlock)
146 gfs2_glock_dq_uninit(&gh);
147 out:
148 gfs2_qa_put(ip);
149 return ret;
150 }
151