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9#include <linux/mnt_namespace.h>
10#include <linux/nsproxy.h>
11#include <linux/security.h>
12#include <linux/fs_struct.h>
13#include "proc/internal.h"
14
15#include "pnode.h"
16#include "internal.h"
17
18static unsigned mounts_poll(struct file *file, poll_table *wait)
19{
20 struct proc_mounts *p = proc_mounts(file->private_data);
21 struct mnt_namespace *ns = p->ns;
22 unsigned res = POLLIN | POLLRDNORM;
23 int event;
24
25 poll_wait(file, &p->ns->poll, wait);
26
27 event = ACCESS_ONCE(ns->event);
28 if (p->m.poll_event != event) {
29 p->m.poll_event = event;
30 res |= POLLERR | POLLPRI;
31 }
32
33 return res;
34}
35
36struct proc_fs_info {
37 int flag;
38 const char *str;
39};
40
41static int show_sb_opts(struct seq_file *m, struct super_block *sb)
42{
43 static const struct proc_fs_info fs_info[] = {
44 { MS_SYNCHRONOUS, ",sync" },
45 { MS_DIRSYNC, ",dirsync" },
46 { MS_MANDLOCK, ",mand" },
47 { 0, NULL }
48 };
49 const struct proc_fs_info *fs_infop;
50
51 for (fs_infop = fs_info; fs_infop->flag; fs_infop++) {
52 if (sb->s_flags & fs_infop->flag)
53 seq_puts(m, fs_infop->str);
54 }
55
56 return security_sb_show_options(m, sb);
57}
58
59static void show_mnt_opts(struct seq_file *m, struct vfsmount *mnt)
60{
61 static const struct proc_fs_info mnt_info[] = {
62 { MNT_NOSUID, ",nosuid" },
63 { MNT_NODEV, ",nodev" },
64 { MNT_NOEXEC, ",noexec" },
65 { MNT_NOATIME, ",noatime" },
66 { MNT_NODIRATIME, ",nodiratime" },
67 { MNT_RELATIME, ",relatime" },
68 { 0, NULL }
69 };
70 const struct proc_fs_info *fs_infop;
71
72 for (fs_infop = mnt_info; fs_infop->flag; fs_infop++) {
73 if (mnt->mnt_flags & fs_infop->flag)
74 seq_puts(m, fs_infop->str);
75 }
76}
77
78static inline void mangle(struct seq_file *m, const char *s)
79{
80 seq_escape(m, s, " \t\n\\");
81}
82
83static void show_type(struct seq_file *m, struct super_block *sb)
84{
85 mangle(m, sb->s_type->name);
86 if (sb->s_subtype && sb->s_subtype[0]) {
87 seq_putc(m, '.');
88 mangle(m, sb->s_subtype);
89 }
90}
91
92static int show_vfsmnt(struct seq_file *m, struct vfsmount *mnt)
93{
94 struct mount *r = real_mount(mnt);
95 int err = 0;
96 struct path mnt_path = { .dentry = mnt->mnt_root, .mnt = mnt };
97 struct super_block *sb = mnt_path.dentry->d_sb;
98
99 if (sb->s_op->show_devname) {
100 err = sb->s_op->show_devname(m, mnt_path.dentry);
101 if (err)
102 goto out;
103 } else {
104 mangle(m, r->mnt_devname ? r->mnt_devname : "none");
105 }
106 seq_putc(m, ' ');
107 seq_path(m, &mnt_path, " \t\n\\");
108 seq_putc(m, ' ');
109 show_type(m, sb);
110 seq_puts(m, __mnt_is_readonly(mnt) ? " ro" : " rw");
111 err = show_sb_opts(m, sb);
112 if (err)
113 goto out;
114 show_mnt_opts(m, mnt);
115 if (sb->s_op->show_options)
116 err = sb->s_op->show_options(m, mnt_path.dentry);
117 seq_puts(m, " 0 0\n");
118out:
119 return err;
120}
121
122static int show_mountinfo(struct seq_file *m, struct vfsmount *mnt)
123{
124 struct proc_mounts *p = proc_mounts(m);
125 struct mount *r = real_mount(mnt);
126 struct super_block *sb = mnt->mnt_sb;
127 struct path mnt_path = { .dentry = mnt->mnt_root, .mnt = mnt };
128 struct path root = p->root;
129 int err = 0;
130
131 seq_printf(m, "%i %i %u:%u ", r->mnt_id, r->mnt_parent->mnt_id,
132 MAJOR(sb->s_dev), MINOR(sb->s_dev));
133 if (sb->s_op->show_path)
134 err = sb->s_op->show_path(m, mnt->mnt_root);
135 else
136 seq_dentry(m, mnt->mnt_root, " \t\n\\");
137 if (err)
138 goto out;
139 seq_putc(m, ' ');
140
141
142 err = seq_path_root(m, &mnt_path, &root, " \t\n\\");
143 if (err)
144 goto out;
145
146 seq_puts(m, mnt->mnt_flags & MNT_READONLY ? " ro" : " rw");
147 show_mnt_opts(m, mnt);
148
149
150 if (IS_MNT_SHARED(r))
151 seq_printf(m, " shared:%i", r->mnt_group_id);
152 if (IS_MNT_SLAVE(r)) {
153 int master = r->mnt_master->mnt_group_id;
154 int dom = get_dominating_id(r, &p->root);
155 seq_printf(m, " master:%i", master);
156 if (dom && dom != master)
157 seq_printf(m, " propagate_from:%i", dom);
158 }
159 if (IS_MNT_UNBINDABLE(r))
160 seq_puts(m, " unbindable");
161
162
163 seq_puts(m, " - ");
164 show_type(m, sb);
165 seq_putc(m, ' ');
166 if (sb->s_op->show_devname)
167 err = sb->s_op->show_devname(m, mnt->mnt_root);
168 else
169 mangle(m, r->mnt_devname ? r->mnt_devname : "none");
170 if (err)
171 goto out;
172 seq_puts(m, sb->s_flags & MS_RDONLY ? " ro" : " rw");
173 err = show_sb_opts(m, sb);
174 if (err)
175 goto out;
176 if (sb->s_op->show_options)
177 err = sb->s_op->show_options(m, mnt->mnt_root);
178 seq_putc(m, '\n');
179out:
180 return err;
181}
182
183static int show_vfsstat(struct seq_file *m, struct vfsmount *mnt)
184{
185 struct mount *r = real_mount(mnt);
186 struct path mnt_path = { .dentry = mnt->mnt_root, .mnt = mnt };
187 struct super_block *sb = mnt_path.dentry->d_sb;
188 int err = 0;
189
190
191 if (sb->s_op->show_devname) {
192 seq_puts(m, "device ");
193 err = sb->s_op->show_devname(m, mnt_path.dentry);
194 } else {
195 if (r->mnt_devname) {
196 seq_puts(m, "device ");
197 mangle(m, r->mnt_devname);
198 } else
199 seq_puts(m, "no device");
200 }
201
202
203 seq_puts(m, " mounted on ");
204 seq_path(m, &mnt_path, " \t\n\\");
205 seq_putc(m, ' ');
206
207
208 seq_puts(m, "with fstype ");
209 show_type(m, sb);
210
211
212 if (sb->s_op->show_stats) {
213 seq_putc(m, ' ');
214 if (!err)
215 err = sb->s_op->show_stats(m, mnt_path.dentry);
216 }
217
218 seq_putc(m, '\n');
219 return err;
220}
221
222static int mounts_open_common(struct inode *inode, struct file *file,
223 int (*show)(struct seq_file *, struct vfsmount *))
224{
225 struct task_struct *task = get_proc_task(inode);
226 struct nsproxy *nsp;
227 struct mnt_namespace *ns = NULL;
228 struct path root;
229 struct proc_mounts *p;
230 int ret = -EINVAL;
231
232 if (!task)
233 goto err;
234
235 task_lock(task);
236 nsp = task->nsproxy;
237 if (!nsp || !nsp->mnt_ns) {
238 task_unlock(task);
239 put_task_struct(task);
240 goto err;
241 }
242 ns = nsp->mnt_ns;
243 get_mnt_ns(ns);
244 if (!task->fs) {
245 task_unlock(task);
246 put_task_struct(task);
247 ret = -ENOENT;
248 goto err_put_ns;
249 }
250 get_fs_root(task->fs, &root);
251 task_unlock(task);
252 put_task_struct(task);
253
254 ret = -ENOMEM;
255 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
256 if (!p)
257 goto err_put_path;
258
259 file->private_data = &p->m;
260 ret = seq_open(file, &mounts_op);
261 if (ret)
262 goto err_free;
263
264 p->ns = ns;
265 p->root = root;
266 p->m.poll_event = ns->event;
267 p->show = show;
268 p->cached_event = ~0ULL;
269
270 return 0;
271
272 err_free:
273 kfree(p);
274 err_put_path:
275 path_put(&root);
276 err_put_ns:
277 put_mnt_ns(ns);
278 err:
279 return ret;
280}
281
282static int mounts_release(struct inode *inode, struct file *file)
283{
284 struct proc_mounts *p = proc_mounts(file->private_data);
285 path_put(&p->root);
286 put_mnt_ns(p->ns);
287 return seq_release(inode, file);
288}
289
290static int mounts_open(struct inode *inode, struct file *file)
291{
292 return mounts_open_common(inode, file, show_vfsmnt);
293}
294
295static int mountinfo_open(struct inode *inode, struct file *file)
296{
297 return mounts_open_common(inode, file, show_mountinfo);
298}
299
300static int mountstats_open(struct inode *inode, struct file *file)
301{
302 return mounts_open_common(inode, file, show_vfsstat);
303}
304
305const struct file_operations proc_mounts_operations = {
306 .open = mounts_open,
307 .read = seq_read,
308 .llseek = seq_lseek,
309 .release = mounts_release,
310 .poll = mounts_poll,
311};
312
313const struct file_operations proc_mountinfo_operations = {
314 .open = mountinfo_open,
315 .read = seq_read,
316 .llseek = seq_lseek,
317 .release = mounts_release,
318 .poll = mounts_poll,
319};
320
321const struct file_operations proc_mountstats_operations = {
322 .open = mountstats_open,
323 .read = seq_read,
324 .llseek = seq_lseek,
325 .release = mounts_release,
326};
327
