acl.c (6f84981772535e670e4e2df051a672af229b6694) acl.c (facd61053cff100973921d4d45d47cf53c747ec6)
1/*
2 * FUSE: Filesystem in Userspace
3 * Copyright (C) 2016 Canonical Ltd. <seth.forshee@canonical.com>
4 *
5 * This program can be distributed under the terms of the GNU GPL.
6 * See the file COPYING.
7 */
8
9#include "fuse_i.h"
10
11#include <linux/posix_acl.h>
12#include <linux/posix_acl_xattr.h>
13
1/*
2 * FUSE: Filesystem in Userspace
3 * Copyright (C) 2016 Canonical Ltd. <seth.forshee@canonical.com>
4 *
5 * This program can be distributed under the terms of the GNU GPL.
6 * See the file COPYING.
7 */
8
9#include "fuse_i.h"
10
11#include <linux/posix_acl.h>
12#include <linux/posix_acl_xattr.h>
13
14struct posix_acl *fuse_get_acl(struct inode *inode, int type, bool rcu)
14static struct posix_acl *__fuse_get_acl(struct fuse_conn *fc,
15 struct user_namespace *mnt_userns,
16 struct inode *inode, int type, bool rcu)
15{
17{
16 struct fuse_conn *fc = get_fuse_conn(inode);
17 int size;
18 const char *name;
19 void *value = NULL;
20 struct posix_acl *acl;
21
22 if (rcu)
23 return ERR_PTR(-ECHILD);
24
25 if (fuse_is_bad(inode))
26 return ERR_PTR(-EIO);
27
18 int size;
19 const char *name;
20 void *value = NULL;
21 struct posix_acl *acl;
22
23 if (rcu)
24 return ERR_PTR(-ECHILD);
25
26 if (fuse_is_bad(inode))
27 return ERR_PTR(-EIO);
28
28 if (!fc->posix_acl || fc->no_getxattr)
29 if (fc->no_getxattr)
29 return NULL;
30
31 if (type == ACL_TYPE_ACCESS)
32 name = XATTR_NAME_POSIX_ACL_ACCESS;
33 else if (type == ACL_TYPE_DEFAULT)
34 name = XATTR_NAME_POSIX_ACL_DEFAULT;
35 else
36 return ERR_PTR(-EOPNOTSUPP);

--- 11 unchanged lines hidden (view full) ---

48 acl = ERR_PTR(-E2BIG);
49 else
50 acl = ERR_PTR(size);
51
52 kfree(value);
53 return acl;
54}
55
30 return NULL;
31
32 if (type == ACL_TYPE_ACCESS)
33 name = XATTR_NAME_POSIX_ACL_ACCESS;
34 else if (type == ACL_TYPE_DEFAULT)
35 name = XATTR_NAME_POSIX_ACL_DEFAULT;
36 else
37 return ERR_PTR(-EOPNOTSUPP);

--- 11 unchanged lines hidden (view full) ---

49 acl = ERR_PTR(-E2BIG);
50 else
51 acl = ERR_PTR(size);
52
53 kfree(value);
54 return acl;
55}
56
57static inline bool fuse_no_acl(const struct fuse_conn *fc,
58 const struct inode *inode)
59{
60 /*
61 * Refuse interacting with POSIX ACLs for daemons that
62 * don't support FUSE_POSIX_ACL and are not mounted on
63 * the host to retain backwards compatibility.
64 */
65 return !fc->posix_acl && (i_user_ns(inode) != &init_user_ns);
66}
67
68struct posix_acl *fuse_get_acl(struct user_namespace *mnt_userns,
69 struct dentry *dentry, int type)
70{
71 struct inode *inode = d_inode(dentry);
72 struct fuse_conn *fc = get_fuse_conn(inode);
73
74 if (fuse_no_acl(fc, inode))
75 return ERR_PTR(-EOPNOTSUPP);
76
77 return __fuse_get_acl(fc, mnt_userns, inode, type, false);
78}
79
80struct posix_acl *fuse_get_inode_acl(struct inode *inode, int type, bool rcu)
81{
82 struct fuse_conn *fc = get_fuse_conn(inode);
83
84 /*
85 * FUSE daemons before FUSE_POSIX_ACL was introduced could get and set
86 * POSIX ACLs without them being used for permission checking by the
87 * vfs. Retain that behavior for backwards compatibility as there are
88 * filesystems that do all permission checking for acls in the daemon
89 * and not in the kernel.
90 */
91 if (!fc->posix_acl)
92 return NULL;
93
94 return __fuse_get_acl(fc, &init_user_ns, inode, type, rcu);
95}
96
56int fuse_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry,
57 struct posix_acl *acl, int type)
58{
59 struct inode *inode = d_inode(dentry);
60 struct fuse_conn *fc = get_fuse_conn(inode);
61 const char *name;
62 int ret;
63
64 if (fuse_is_bad(inode))
65 return -EIO;
66
97int fuse_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry,
98 struct posix_acl *acl, int type)
99{
100 struct inode *inode = d_inode(dentry);
101 struct fuse_conn *fc = get_fuse_conn(inode);
102 const char *name;
103 int ret;
104
105 if (fuse_is_bad(inode))
106 return -EIO;
107
67 if (!fc->posix_acl || fc->no_setxattr)
108 if (fc->no_setxattr || fuse_no_acl(fc, inode))
68 return -EOPNOTSUPP;
69
70 if (type == ACL_TYPE_ACCESS)
71 name = XATTR_NAME_POSIX_ACL_ACCESS;
72 else if (type == ACL_TYPE_DEFAULT)
73 name = XATTR_NAME_POSIX_ACL_DEFAULT;
74 else
75 return -EINVAL;

--- 18 unchanged lines hidden (view full) ---

94 return -ENOMEM;
95
96 ret = posix_acl_to_xattr(fc->user_ns, acl, value, size);
97 if (ret < 0) {
98 kfree(value);
99 return ret;
100 }
101
109 return -EOPNOTSUPP;
110
111 if (type == ACL_TYPE_ACCESS)
112 name = XATTR_NAME_POSIX_ACL_ACCESS;
113 else if (type == ACL_TYPE_DEFAULT)
114 name = XATTR_NAME_POSIX_ACL_DEFAULT;
115 else
116 return -EINVAL;

--- 18 unchanged lines hidden (view full) ---

135 return -ENOMEM;
136
137 ret = posix_acl_to_xattr(fc->user_ns, acl, value, size);
138 if (ret < 0) {
139 kfree(value);
140 return ret;
141 }
142
102 if (!vfsgid_in_group_p(i_gid_into_vfsgid(&init_user_ns, inode)) &&
143 /*
144 * Fuse daemons without FUSE_POSIX_ACL never changed the passed
145 * through POSIX ACLs. Such daemons don't expect setgid bits to
146 * be stripped.
147 */
148 if (fc->posix_acl &&
149 !vfsgid_in_group_p(i_gid_into_vfsgid(&init_user_ns, inode)) &&
103 !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
104 extra_flags |= FUSE_SETXATTR_ACL_KILL_SGID;
105
106 ret = fuse_setxattr(inode, name, value, size, 0, extra_flags);
107 kfree(value);
108 } else {
109 ret = fuse_removexattr(inode, name);
110 }
150 !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
151 extra_flags |= FUSE_SETXATTR_ACL_KILL_SGID;
152
153 ret = fuse_setxattr(inode, name, value, size, 0, extra_flags);
154 kfree(value);
155 } else {
156 ret = fuse_removexattr(inode, name);
157 }
111 forget_all_cached_acls(inode);
112 fuse_invalidate_attr(inode);
113
158
159 if (fc->posix_acl) {
160 /*
161 * Fuse daemons without FUSE_POSIX_ACL never cached POSIX ACLs
162 * and didn't invalidate attributes. Retain that behavior.
163 */
164 forget_all_cached_acls(inode);
165 fuse_invalidate_attr(inode);
166 }
167
114 return ret;
115}
168 return ret;
169}