fs/notify/fdinfo.c

   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/proc_fs.h>
  15 #include <linux/exportfs.h>
  16
  17 #include "inotify/inotify.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         mutex_lock(&group->mark_mutex);
  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         mutex_unlock(&group->mark_mutex);
  39 }
  40
  41 #if defined(CONFIG_EXPORTFS)
  42 static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
  43 {
  44         struct {
  45                 struct file_handle handle;
  46                 u8 pad[MAX_HANDLE_SZ];
  47         } f;
  48         int size, ret, i;
  49
  50         f.handle.handle_bytes = sizeof(f.pad);
  51         size = f.handle.handle_bytes >> 2;
  52
  53         ret = exportfs_encode_inode_fh(inode, (struct fid *)f.handle.f_handle, &size, 0);
  54         if ((ret == FILEID_INVALID) || (ret < 0)) {
  55                 WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret);
  56                 return;
  57         }
  58
  59         f.handle.handle_type = ret;
  60         f.handle.handle_bytes = size * sizeof(u32);
  61
  62         seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:",
  63                    f.handle.handle_bytes, f.handle.handle_type);
  64
  65         for (i = 0; i < f.handle.handle_bytes; i++)
  66                 seq_printf(m, "%02x", (int)f.handle.f_handle[i]);
  67 }
  68 #else
  69 static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
  70 {
  71 }
  72 #endif
  73
  74 #ifdef CONFIG_INOTIFY_USER
  75
  76 static void inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
  77 {
  78         struct inotify_inode_mark *inode_mark;
  79         struct inode *inode;
  80
  81         if (mark->connector->type != FSNOTIFY_OBJ_TYPE_INODE)
  82                 return;
  83
  84         inode_mark = container_of(mark, struct inotify_inode_mark, fsn_mark);
  85         inode = igrab(fsnotify_conn_inode(mark->connector));
  86         if (inode) {
  87                 /*
  88                  * IN_ALL_EVENTS represents all of the mask bits
  89                  * that we expose to userspace.  There is at
  90                  * least one bit (FS_EVENT_ON_CHILD) which is
  91                  * used only internally to the kernel.
  92                  */
  93                 u32 mask = mark->mask & IN_ALL_EVENTS;
  94                 seq_printf(m, "inotify wd:%x ino:%lx sdev:%x mask:%x ignored_mask:%x ",
  95                            inode_mark->wd, inode->i_ino, inode->i_sb->s_dev,
  96                            mask, mark->ignored_mask);
  97                 show_mark_fhandle(m, inode);
  98                 seq_putc(m, '\n');
  99                 iput(inode);
 100         }
 101 }
 102
 103 void inotify_show_fdinfo(struct seq_file *m, struct file *f)
 104 {
 105         show_fdinfo(m, f, inotify_fdinfo);
 106 }
 107
 108 #endif /* CONFIG_INOTIFY_USER */
 109
 110 #ifdef CONFIG_FANOTIFY
 111
 112 static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
 113 {
 114         unsigned int mflags = 0;
 115         struct inode *inode;
 116
 117         if (mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY)
 118                 mflags |= FAN_MARK_IGNORED_SURV_MODIFY;
 119
 120         if (mark->connector->type == FSNOTIFY_OBJ_TYPE_INODE) {
 121                 inode = igrab(fsnotify_conn_inode(mark->connector));
 122                 if (!inode)
 123                         return;
 124                 seq_printf(m, "fanotify ino:%lx sdev:%x mflags:%x mask:%x ignored_mask:%x ",
 125                            inode->i_ino, inode->i_sb->s_dev,
 126                            mflags, mark->mask, mark->ignored_mask);
 127                 show_mark_fhandle(m, inode);
 128                 seq_putc(m, '\n');
 129                 iput(inode);
 130         } else if (mark->connector->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) {
 131                 struct mount *mnt = fsnotify_conn_mount(mark->connector);
 132
 133                 seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x ignored_mask:%x\n",
 134                            mnt->mnt_id, mflags, mark->mask, mark->ignored_mask);
 135         } else if (mark->connector->type == FSNOTIFY_OBJ_TYPE_SB) {
 136                 struct super_block *sb = fsnotify_conn_sb(mark->connector);
 137
 138                 seq_printf(m, "fanotify sdev:%x mflags:%x mask:%x ignored_mask:%x\n",
 139                            sb->s_dev, mflags, mark->mask, mark->ignored_mask);
 140         }
 141 }
 142
 143 void fanotify_show_fdinfo(struct seq_file *m, struct file *f)
 144 {
 145         struct fsnotify_group *group = f->private_data;
 146
 147         seq_printf(m, "fanotify flags:%x event-flags:%x\n",
 148                    group->fanotify_data.flags, group->fanotify_data.f_flags);
 149
 150         show_fdinfo(m, f, fanotify_fdinfo);
 151 }
 152
 153 #endif /* CONFIG_FANOTIFY */
 154
 155 #endif /* CONFIG_INOTIFY_USER || CONFIG_FANOTIFY */
 156
 157 #endif /* CONFIG_PROC_FS */