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 "rgrp.h"
25 #include "trans.h"
26 #include "util.h"
27
gfs2_acl_name(int type)28 static const char *gfs2_acl_name(int type)
29 {
30 switch (type) {
31 case ACL_TYPE_ACCESS:
32 return XATTR_POSIX_ACL_ACCESS;
33 case ACL_TYPE_DEFAULT:
34 return XATTR_POSIX_ACL_DEFAULT;
35 }
36 return NULL;
37 }
38
__gfs2_get_acl(struct inode * inode,int type)39 static struct posix_acl *__gfs2_get_acl(struct inode *inode, int type)
40 {
41 struct gfs2_inode *ip = GFS2_I(inode);
42 struct posix_acl *acl;
43 const char *name;
44 char *data;
45 int len;
46
47 if (!ip->i_eattr)
48 return NULL;
49
50 name = gfs2_acl_name(type);
51 len = gfs2_xattr_acl_get(ip, name, &data);
52 if (len <= 0)
53 return ERR_PTR(len);
54 acl = posix_acl_from_xattr(&init_user_ns, data, len);
55 kfree(data);
56 return acl;
57 }
58
gfs2_get_acl(struct inode * inode,int type)59 struct posix_acl *gfs2_get_acl(struct inode *inode, int type)
60 {
61 struct gfs2_inode *ip = GFS2_I(inode);
62 struct gfs2_holder gh;
63 bool need_unlock = false;
64 struct posix_acl *acl;
65
66 if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
67 int ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
68 LM_FLAG_ANY, &gh);
69 if (ret)
70 return ERR_PTR(ret);
71 need_unlock = true;
72 }
73 acl = __gfs2_get_acl(inode, type);
74 if (need_unlock)
75 gfs2_glock_dq_uninit(&gh);
76 return acl;
77 }
78
__gfs2_set_acl(struct inode * inode,struct posix_acl * acl,int type)79 int __gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
80 {
81 int error;
82 size_t len;
83 char *data;
84 const char *name = gfs2_acl_name(type);
85
86 if (acl) {
87 len = posix_acl_xattr_size(acl->a_count);
88 data = kmalloc(len, GFP_NOFS);
89 if (data == NULL)
90 return -ENOMEM;
91 error = posix_acl_to_xattr(&init_user_ns, acl, data, len);
92 if (error < 0)
93 goto out;
94 } else {
95 data = NULL;
96 len = 0;
97 }
98
99 error = __gfs2_xattr_set(inode, name, data, len, 0, GFS2_EATYPE_SYS);
100 if (error)
101 goto out;
102 set_cached_acl(inode, type, acl);
103 out:
104 kfree(data);
105 return error;
106 }
107
gfs2_set_acl(struct inode * inode,struct posix_acl * acl,int type)108 int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
109 {
110 struct gfs2_inode *ip = GFS2_I(inode);
111 struct gfs2_holder gh;
112 bool need_unlock = false;
113 int ret;
114 umode_t mode;
115
116 if (acl && acl->a_count > GFS2_ACL_MAX_ENTRIES(GFS2_SB(inode)))
117 return -E2BIG;
118
119 ret = gfs2_rsqa_alloc(ip);
120 if (ret)
121 return ret;
122
123 if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
124 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
125 if (ret)
126 return ret;
127 need_unlock = true;
128 }
129
130 mode = inode->i_mode;
131 if (type == ACL_TYPE_ACCESS && acl) {
132 ret = posix_acl_update_mode(inode, &mode, &acl);
133 if (ret)
134 goto unlock;
135 }
136
137 ret = __gfs2_set_acl(inode, acl, type);
138 if (!ret && mode != inode->i_mode) {
139 inode->i_ctime = current_time(inode);
140 inode->i_mode = mode;
141 mark_inode_dirty(inode);
142 }
143 unlock:
144 if (need_unlock)
145 gfs2_glock_dq_uninit(&gh);
146 return ret;
147 }
148