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6#include <linux/init.h>
7#include <linux/mount.h>
8#include <linux/namei.h>
9#include <linux/fs.h>
10#include <linux/fs_struct.h>
11#include <linux/file.h>
12#include <linux/init_syscalls.h>
13#include <linux/security.h>
14#include "internal.h"
15
16int __init init_mount(const char *dev_name, const char *dir_name,
17 const char *type_page, unsigned long flags, void *data_page)
18{
19 struct path path;
20 int ret;
21
22 ret = kern_path(dir_name, LOOKUP_FOLLOW, &path);
23 if (ret)
24 return ret;
25 ret = path_mount(dev_name, &path, type_page, flags, data_page);
26 path_put(&path);
27 return ret;
28}
29
30int __init init_umount(const char *name, int flags)
31{
32 int lookup_flags = LOOKUP_MOUNTPOINT;
33 struct path path;
34 int ret;
35
36 if (!(flags & UMOUNT_NOFOLLOW))
37 lookup_flags |= LOOKUP_FOLLOW;
38 ret = kern_path(name, lookup_flags, &path);
39 if (ret)
40 return ret;
41 return path_umount(&path, flags);
42}
43
44int __init init_chdir(const char *filename)
45{
46 struct path path;
47 int error;
48
49 error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
50 if (error)
51 return error;
52 error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
53 if (!error)
54 set_fs_pwd(current->fs, &path);
55 path_put(&path);
56 return error;
57}
58
59int __init init_chroot(const char *filename)
60{
61 struct path path;
62 int error;
63
64 error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
65 if (error)
66 return error;
67 error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
68 if (error)
69 goto dput_and_out;
70 error = -EPERM;
71 if (!ns_capable(current_user_ns(), CAP_SYS_CHROOT))
72 goto dput_and_out;
73 error = security_path_chroot(&path);
74 if (error)
75 goto dput_and_out;
76 set_fs_root(current->fs, &path);
77dput_and_out:
78 path_put(&path);
79 return error;
80}
81
82int __init init_chown(const char *filename, uid_t user, gid_t group, int flags)
83{
84 int lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
85 struct path path;
86 int error;
87
88 error = kern_path(filename, lookup_flags, &path);
89 if (error)
90 return error;
91 error = mnt_want_write(path.mnt);
92 if (!error) {
93 error = chown_common(&path, user, group);
94 mnt_drop_write(path.mnt);
95 }
96 path_put(&path);
97 return error;
98}
99
100int __init init_chmod(const char *filename, umode_t mode)
101{
102 struct path path;
103 int error;
104
105 error = kern_path(filename, LOOKUP_FOLLOW, &path);
106 if (error)
107 return error;
108 error = chmod_common(&path, mode);
109 path_put(&path);
110 return error;
111}
112
113int __init init_eaccess(const char *filename)
114{
115 struct path path;
116 int error;
117
118 error = kern_path(filename, LOOKUP_FOLLOW, &path);
119 if (error)
120 return error;
121 error = inode_permission(d_inode(path.dentry), MAY_ACCESS);
122 path_put(&path);
123 return error;
124}
125
126int __init init_stat(const char *filename, struct kstat *stat, int flags)
127{
128 int lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
129 struct path path;
130 int error;
131
132 error = kern_path(filename, lookup_flags, &path);
133 if (error)
134 return error;
135 error = vfs_getattr(&path, stat, STATX_BASIC_STATS,
136 flags | AT_NO_AUTOMOUNT);
137 path_put(&path);
138 return error;
139}
140
141int __init init_mknod(const char *filename, umode_t mode, unsigned int dev)
142{
143 struct dentry *dentry;
144 struct path path;
145 int error;
146
147 if (S_ISFIFO(mode) || S_ISSOCK(mode))
148 dev = 0;
149 else if (!(S_ISBLK(mode) || S_ISCHR(mode)))
150 return -EINVAL;
151
152 dentry = kern_path_create(AT_FDCWD, filename, &path, 0);
153 if (IS_ERR(dentry))
154 return PTR_ERR(dentry);
155
156 if (!IS_POSIXACL(path.dentry->d_inode))
157 mode &= ~current_umask();
158 error = security_path_mknod(&path, dentry, mode, dev);
159 if (!error)
160 error = vfs_mknod(path.dentry->d_inode, dentry, mode,
161 new_decode_dev(dev));
162 done_path_create(&path, dentry);
163 return error;
164}
165
166int __init init_link(const char *oldname, const char *newname)
167{
168 struct dentry *new_dentry;
169 struct path old_path, new_path;
170 int error;
171
172 error = kern_path(oldname, 0, &old_path);
173 if (error)
174 return error;
175
176 new_dentry = kern_path_create(AT_FDCWD, newname, &new_path, 0);
177 error = PTR_ERR(new_dentry);
178 if (IS_ERR(new_dentry))
179 goto out;
180
181 error = -EXDEV;
182 if (old_path.mnt != new_path.mnt)
183 goto out_dput;
184 error = may_linkat(&old_path);
185 if (unlikely(error))
186 goto out_dput;
187 error = security_path_link(old_path.dentry, &new_path, new_dentry);
188 if (error)
189 goto out_dput;
190 error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry,
191 NULL);
192out_dput:
193 done_path_create(&new_path, new_dentry);
194out:
195 path_put(&old_path);
196 return error;
197}
198
199int __init init_symlink(const char *oldname, const char *newname)
200{
201 struct dentry *dentry;
202 struct path path;
203 int error;
204
205 dentry = kern_path_create(AT_FDCWD, newname, &path, 0);
206 if (IS_ERR(dentry))
207 return PTR_ERR(dentry);
208 error = security_path_symlink(&path, dentry, oldname);
209 if (!error)
210 error = vfs_symlink(path.dentry->d_inode, dentry, oldname);
211 done_path_create(&path, dentry);
212 return error;
213}
214
215int __init init_unlink(const char *pathname)
216{
217 return do_unlinkat(AT_FDCWD, getname_kernel(pathname));
218}
219
220int __init init_mkdir(const char *pathname, umode_t mode)
221{
222 struct dentry *dentry;
223 struct path path;
224 int error;
225
226 dentry = kern_path_create(AT_FDCWD, pathname, &path, LOOKUP_DIRECTORY);
227 if (IS_ERR(dentry))
228 return PTR_ERR(dentry);
229 if (!IS_POSIXACL(path.dentry->d_inode))
230 mode &= ~current_umask();
231 error = security_path_mkdir(&path, dentry, mode);
232 if (!error)
233 error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
234 done_path_create(&path, dentry);
235 return error;
236}
237
238int __init init_rmdir(const char *pathname)
239{
240 return do_rmdir(AT_FDCWD, getname_kernel(pathname));
241}
242
243int __init init_utimes(char *filename, struct timespec64 *ts)
244{
245 struct path path;
246 int error;
247
248 error = kern_path(filename, 0, &path);
249 if (error)
250 return error;
251 error = vfs_utimes(&path, ts);
252 path_put(&path);
253 return error;
254}
255
256int __init init_dup(struct file *file)
257{
258 int fd;
259
260 fd = get_unused_fd_flags(0);
261 if (fd < 0)
262 return fd;
263 fd_install(fd, get_file(file));
264 return 0;
265}
266
