xref: /linux/fs/notify/fdinfo.c (revision ab52c59103002b49f2455371e4b9c56ba3ef1781)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/file.h>
3 #include <linux/fs.h>
4 #include <linux/fsnotify_backend.h>
5 #include <linux/idr.h>
6 #include <linux/init.h>
7 #include <linux/inotify.h>
8 #include <linux/fanotify.h>
9 #include <linux/kernel.h>
10 #include <linux/namei.h>
11 #include <linux/sched.h>
12 #include <linux/types.h>
13 #include <linux/seq_file.h>
14 #include <linux/exportfs.h>
15 
16 #include "inotify/inotify.h"
17 #include "fanotify/fanotify.h"
18 #include "fdinfo.h"
19 #include "fsnotify.h"
20 
21 #if defined(CONFIG_PROC_FS)
22 
23 #if defined(CONFIG_INOTIFY_USER) || defined(CONFIG_FANOTIFY)
24 
25 static void show_fdinfo(struct seq_file *m, struct file *f,
26 			void (*show)(struct seq_file *m,
27 				     struct fsnotify_mark *mark))
28 {
29 	struct fsnotify_group *group = f->private_data;
30 	struct fsnotify_mark *mark;
31 
32 	fsnotify_group_lock(group);
33 	list_for_each_entry(mark, &group->marks_list, g_list) {
34 		show(m, mark);
35 		if (seq_has_overflowed(m))
36 			break;
37 	}
38 	fsnotify_group_unlock(group);
39 }
40 
41 #if defined(CONFIG_EXPORTFS)
42 static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
43 {
44 	DEFINE_FLEX(struct file_handle, f, f_handle, handle_bytes, MAX_HANDLE_SZ);
45 	int size, ret, i;
46 
47 	size = f->handle_bytes >> 2;
48 
49 	ret = exportfs_encode_fid(inode, (struct fid *)f->f_handle, &size);
50 	if ((ret == FILEID_INVALID) || (ret < 0)) {
51 		WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret);
52 		return;
53 	}
54 
55 	f->handle_type = ret;
56 	f->handle_bytes = size * sizeof(u32);
57 
58 	seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:",
59 		   f->handle_bytes, f->handle_type);
60 
61 	for (i = 0; i < f->handle_bytes; i++)
62 		seq_printf(m, "%02x", (int)f->f_handle[i]);
63 }
64 #else
65 static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
66 {
67 }
68 #endif
69 
70 #ifdef CONFIG_INOTIFY_USER
71 
72 static void inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
73 {
74 	struct inotify_inode_mark *inode_mark;
75 	struct inode *inode;
76 
77 	if (mark->connector->type != FSNOTIFY_OBJ_TYPE_INODE)
78 		return;
79 
80 	inode_mark = container_of(mark, struct inotify_inode_mark, fsn_mark);
81 	inode = igrab(fsnotify_conn_inode(mark->connector));
82 	if (inode) {
83 		seq_printf(m, "inotify wd:%x ino:%lx sdev:%x mask:%x ignored_mask:0 ",
84 			   inode_mark->wd, inode->i_ino, inode->i_sb->s_dev,
85 			   inotify_mark_user_mask(mark));
86 		show_mark_fhandle(m, inode);
87 		seq_putc(m, '\n');
88 		iput(inode);
89 	}
90 }
91 
92 void inotify_show_fdinfo(struct seq_file *m, struct file *f)
93 {
94 	show_fdinfo(m, f, inotify_fdinfo);
95 }
96 
97 #endif /* CONFIG_INOTIFY_USER */
98 
99 #ifdef CONFIG_FANOTIFY
100 
101 static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
102 {
103 	unsigned int mflags = fanotify_mark_user_flags(mark);
104 	struct inode *inode;
105 
106 	if (mark->connector->type == FSNOTIFY_OBJ_TYPE_INODE) {
107 		inode = igrab(fsnotify_conn_inode(mark->connector));
108 		if (!inode)
109 			return;
110 		seq_printf(m, "fanotify ino:%lx sdev:%x mflags:%x mask:%x ignored_mask:%x ",
111 			   inode->i_ino, inode->i_sb->s_dev,
112 			   mflags, mark->mask, mark->ignore_mask);
113 		show_mark_fhandle(m, inode);
114 		seq_putc(m, '\n');
115 		iput(inode);
116 	} else if (mark->connector->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) {
117 		struct mount *mnt = fsnotify_conn_mount(mark->connector);
118 
119 		seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x ignored_mask:%x\n",
120 			   mnt->mnt_id, mflags, mark->mask, mark->ignore_mask);
121 	} else if (mark->connector->type == FSNOTIFY_OBJ_TYPE_SB) {
122 		struct super_block *sb = fsnotify_conn_sb(mark->connector);
123 
124 		seq_printf(m, "fanotify sdev:%x mflags:%x mask:%x ignored_mask:%x\n",
125 			   sb->s_dev, mflags, mark->mask, mark->ignore_mask);
126 	}
127 }
128 
129 void fanotify_show_fdinfo(struct seq_file *m, struct file *f)
130 {
131 	struct fsnotify_group *group = f->private_data;
132 
133 	seq_printf(m, "fanotify flags:%x event-flags:%x\n",
134 		   group->fanotify_data.flags & FANOTIFY_INIT_FLAGS,
135 		   group->fanotify_data.f_flags);
136 
137 	show_fdinfo(m, f, fanotify_fdinfo);
138 }
139 
140 #endif /* CONFIG_FANOTIFY */
141 
142 #endif /* CONFIG_INOTIFY_USER || CONFIG_FANOTIFY */
143 
144 #endif /* CONFIG_PROC_FS */
145