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 "../fs/mount.h"
  19
  20 #if defined(CONFIG_PROC_FS)
  21
  22 #if defined(CONFIG_INOTIFY_USER) || defined(CONFIG_FANOTIFY)
  23
  24 static void show_fdinfo(struct seq_file *m, struct file *f,
  25                         void (*show)(struct seq_file *m,
  26                                      struct fsnotify_mark *mark))
  27 {
  28         struct fsnotify_group *group = f->private_data;
  29         struct fsnotify_mark *mark;
  30
  31         mutex_lock(&group->mark_mutex);
  32         list_for_each_entry(mark, &group->marks_list, g_list) {
  33                 show(m, mark);
  34                 if (seq_has_overflowed(m))
  35                         break;
  36         }
  37         mutex_unlock(&group->mark_mutex);
  38 }
  39
  40 #if defined(CONFIG_EXPORTFS)
  41 static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
  42 {
  43         struct {
  44                 struct file_handle handle;
  45                 u8 pad[MAX_HANDLE_SZ];
  46         } f;
  47         int size, ret, i;
  48
  49         f.handle.handle_bytes = sizeof(f.pad);
  50         size = f.handle.handle_bytes >> 2;
  51
  52         ret = exportfs_encode_inode_fh(inode, (struct fid *)f.handle.f_handle, &size, 0);
  53         if ((ret == FILEID_INVALID) || (ret < 0)) {
  54                 WARN_ONCE(1, "Can't encode file handler for inotify: %d\n", ret);
  55                 return;
  56         }
  57
  58         f.handle.handle_type = ret;
  59         f.handle.handle_bytes = size * sizeof(u32);
  60
  61         seq_printf(m, "fhandle-bytes:%x fhandle-type:%x f_handle:",
  62                    f.handle.handle_bytes, f.handle.handle_type);
  63
  64         for (i = 0; i < f.handle.handle_bytes; i++)
  65                 seq_printf(m, "%02x", (int)f.handle.f_handle[i]);
  66 }
  67 #else
  68 static void show_mark_fhandle(struct seq_file *m, struct inode *inode)
  69 {
  70 }
  71 #endif
  72
  73 #ifdef CONFIG_INOTIFY_USER
  74
  75 static void inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
  76 {
  77         struct inotify_inode_mark *inode_mark;
  78         struct inode *inode;
  79
  80         if (mark->connector->type != FSNOTIFY_OBJ_TYPE_INODE)
  81                 return;
  82
  83         inode_mark = container_of(mark, struct inotify_inode_mark, fsn_mark);
  84         inode = igrab(mark->connector->inode);
  85         if (inode) {
  86                 /*
  87                  * IN_ALL_EVENTS represents all of the mask bits
  88                  * that we expose to userspace.  There is at
  89                  * least one bit (FS_EVENT_ON_CHILD) which is
  90                  * used only internally to the kernel.
  91                  */
  92                 u32 mask = mark->mask & IN_ALL_EVENTS;
  93                 seq_printf(m, "inotify wd:%x ino:%lx sdev:%x mask:%x ignored_mask:%x ",
  94                            inode_mark->wd, inode->i_ino, inode->i_sb->s_dev,
  95                            mask, mark->ignored_mask);
  96                 show_mark_fhandle(m, inode);
  97                 seq_putc(m, '\n');
  98                 iput(inode);
  99         }
 100 }
 101
 102 void inotify_show_fdinfo(struct seq_file *m, struct file *f)
 103 {
 104         show_fdinfo(m, f, inotify_fdinfo);
 105 }
 106
 107 #endif /* CONFIG_INOTIFY_USER */
 108
 109 #ifdef CONFIG_FANOTIFY
 110
 111 static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
 112 {
 113         unsigned int mflags = 0;
 114         struct inode *inode;
 115
 116         if (mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY)
 117                 mflags |= FAN_MARK_IGNORED_SURV_MODIFY;
 118
 119         if (mark->connector->type == FSNOTIFY_OBJ_TYPE_INODE) {
 120                 inode = igrab(mark->connector->inode);
 121                 if (!inode)
 122                         return;
 123                 seq_printf(m, "fanotify ino:%lx sdev:%x mflags:%x mask:%x ignored_mask:%x ",
 124                            inode->i_ino, inode->i_sb->s_dev,
 125                            mflags, mark->mask, mark->ignored_mask);
 126                 show_mark_fhandle(m, inode);
 127                 seq_putc(m, '\n');
 128                 iput(inode);
 129         } else if (mark->connector->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) {
 130                 struct mount *mnt = real_mount(mark->connector->mnt);
 131
 132                 seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x ignored_mask:%x\n",
 133                            mnt->mnt_id, mflags, mark->mask, mark->ignored_mask);
 134         }
 135 }
 136
 137 void fanotify_show_fdinfo(struct seq_file *m, struct file *f)
 138 {
 139         struct fsnotify_group *group = f->private_data;
 140         unsigned int flags = 0;
 141
 142         switch (group->priority) {
 143         case FS_PRIO_0:
 144                 flags |= FAN_CLASS_NOTIF;
 145                 break;
 146         case FS_PRIO_1:
 147                 flags |= FAN_CLASS_CONTENT;
 148                 break;
 149         case FS_PRIO_2:
 150                 flags |= FAN_CLASS_PRE_CONTENT;
 151                 break;
 152         }
 153
 154         if (group->max_events == UINT_MAX)
 155                 flags |= FAN_UNLIMITED_QUEUE;
 156
 157         if (group->fanotify_data.max_marks == UINT_MAX)
 158                 flags |= FAN_UNLIMITED_MARKS;
 159
 160         if (group->fanotify_data.audit)
 161                 flags |= FAN_ENABLE_AUDIT;
 162
 163         seq_printf(m, "fanotify flags:%x event-flags:%x\n",
 164                    flags, group->fanotify_data.f_flags);
 165
 166         show_fdinfo(m, f, fanotify_fdinfo);
 167 }
 168
 169 #endif /* CONFIG_FANOTIFY */
 170
 171 #endif /* CONFIG_INOTIFY_USER || CONFIG_FANOTIFY */
 172
 173 #endif /* CONFIG_PROC_FS */