Andreas Gruenbacher | 33d3dff | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 1 | #include <linux/fanotify.h> |
Eric Paris | 11637e4 | 2009-12-17 21:24:25 -0500 | [diff] [blame] | 2 | #include <linux/fcntl.h> |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 3 | #include <linux/file.h> |
Eric Paris | 11637e4 | 2009-12-17 21:24:25 -0500 | [diff] [blame] | 4 | #include <linux/fs.h> |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 5 | #include <linux/anon_inodes.h> |
Eric Paris | 11637e4 | 2009-12-17 21:24:25 -0500 | [diff] [blame] | 6 | #include <linux/fsnotify_backend.h> |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 7 | #include <linux/init.h> |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 8 | #include <linux/mount.h> |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 9 | #include <linux/namei.h> |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 10 | #include <linux/poll.h> |
Eric Paris | 11637e4 | 2009-12-17 21:24:25 -0500 | [diff] [blame] | 11 | #include <linux/security.h> |
| 12 | #include <linux/syscalls.h> |
Tejun Heo | e4e047a | 2010-05-20 01:36:28 +1000 | [diff] [blame] | 13 | #include <linux/slab.h> |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 14 | #include <linux/types.h> |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 15 | #include <linux/uaccess.h> |
Al Viro | 91c2e0b | 2013-03-05 20:10:59 -0500 | [diff] [blame] | 16 | #include <linux/compat.h> |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 17 | |
| 18 | #include <asm/ioctls.h> |
Eric Paris | 11637e4 | 2009-12-17 21:24:25 -0500 | [diff] [blame] | 19 | |
Al Viro | c63181e | 2011-11-25 02:35:16 -0500 | [diff] [blame] | 20 | #include "../../mount.h" |
Cyrill Gorcunov | be77196 | 2012-12-17 16:05:12 -0800 | [diff] [blame] | 21 | #include "../fdinfo.h" |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 22 | #include "fanotify.h" |
Al Viro | c63181e | 2011-11-25 02:35:16 -0500 | [diff] [blame] | 23 | |
Eric Paris | 2529a0d | 2010-10-28 17:21:57 -0400 | [diff] [blame] | 24 | #define FANOTIFY_DEFAULT_MAX_EVENTS 16384 |
Eric Paris | e7099d8 | 2010-10-28 17:21:57 -0400 | [diff] [blame] | 25 | #define FANOTIFY_DEFAULT_MAX_MARKS 8192 |
Eric Paris | 4afeff8 | 2010-10-28 17:21:58 -0400 | [diff] [blame] | 26 | #define FANOTIFY_DEFAULT_MAX_LISTENERS 128 |
Eric Paris | 2529a0d | 2010-10-28 17:21:57 -0400 | [diff] [blame] | 27 | |
Heinrich Schuchardt | 48149e9 | 2014-06-04 16:05:44 -0700 | [diff] [blame] | 28 | /* |
| 29 | * All flags that may be specified in parameter event_f_flags of fanotify_init. |
| 30 | * |
| 31 | * Internal and external open flags are stored together in field f_flags of |
| 32 | * struct file. Only external open flags shall be allowed in event_f_flags. |
| 33 | * Internal flags like FMODE_NONOTIFY, FMODE_EXEC, FMODE_NOCMTIME shall be |
| 34 | * excluded. |
| 35 | */ |
| 36 | #define FANOTIFY_INIT_ALL_EVENT_F_BITS ( \ |
| 37 | O_ACCMODE | O_APPEND | O_NONBLOCK | \ |
| 38 | __O_SYNC | O_DSYNC | O_CLOEXEC | \ |
| 39 | O_LARGEFILE | O_NOATIME ) |
| 40 | |
Andreas Gruenbacher | 33d3dff | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 41 | extern const struct fsnotify_ops fanotify_fsnotify_ops; |
Eric Paris | 11637e4 | 2009-12-17 21:24:25 -0500 | [diff] [blame] | 42 | |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 43 | static struct kmem_cache *fanotify_mark_cache __read_mostly; |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 44 | struct kmem_cache *fanotify_event_cachep __read_mostly; |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 45 | struct kmem_cache *fanotify_perm_event_cachep __read_mostly; |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 46 | |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 47 | /* |
| 48 | * Get an fsnotify notification event if one exists and is small |
| 49 | * enough to fit in "count". Return an error pointer if the count |
| 50 | * is not large enough. |
| 51 | * |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 52 | * Called with the group->notification_lock held. |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 53 | */ |
| 54 | static struct fsnotify_event *get_one_event(struct fsnotify_group *group, |
| 55 | size_t count) |
| 56 | { |
Jan Kara | ed27264 | 2016-10-07 16:57:01 -0700 | [diff] [blame] | 57 | assert_spin_locked(&group->notification_lock); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 58 | |
| 59 | pr_debug("%s: group=%p count=%zd\n", __func__, group, count); |
| 60 | |
| 61 | if (fsnotify_notify_queue_is_empty(group)) |
| 62 | return NULL; |
| 63 | |
| 64 | if (FAN_EVENT_METADATA_LEN > count) |
| 65 | return ERR_PTR(-EINVAL); |
| 66 | |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 67 | /* held the notification_lock the whole time, so this is the |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 68 | * same event we peeked above */ |
Jan Kara | 8ba8fa91 | 2014-08-06 16:03:26 -0700 | [diff] [blame] | 69 | return fsnotify_remove_first_event(group); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 70 | } |
| 71 | |
Al Viro | 352e3b2 | 2012-08-19 12:30:45 -0400 | [diff] [blame] | 72 | static int create_fd(struct fsnotify_group *group, |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 73 | struct fanotify_event_info *event, |
| 74 | struct file **file) |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 75 | { |
| 76 | int client_fd; |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 77 | struct file *new_file; |
| 78 | |
Andreas Gruenbacher | 22aa425 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 79 | pr_debug("%s: group=%p event=%p\n", __func__, group, event); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 80 | |
Yann Droneaud | 0b37e09 | 2014-10-09 15:24:40 -0700 | [diff] [blame] | 81 | client_fd = get_unused_fd_flags(group->fanotify_data.f_flags); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 82 | if (client_fd < 0) |
| 83 | return client_fd; |
| 84 | |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 85 | /* |
| 86 | * we need a new file handle for the userspace program so it can read even if it was |
| 87 | * originally opened O_WRONLY. |
| 88 | */ |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 89 | /* it's possible this event was an overflow event. in that case dentry and mnt |
| 90 | * are NULL; That's fine, just don't call dentry open */ |
Al Viro | 765927b | 2012-06-26 21:58:53 +0400 | [diff] [blame] | 91 | if (event->path.dentry && event->path.mnt) |
| 92 | new_file = dentry_open(&event->path, |
Eric Paris | 80af258 | 2010-07-28 10:18:37 -0400 | [diff] [blame] | 93 | group->fanotify_data.f_flags | FMODE_NONOTIFY, |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 94 | current_cred()); |
| 95 | else |
| 96 | new_file = ERR_PTR(-EOVERFLOW); |
| 97 | if (IS_ERR(new_file)) { |
| 98 | /* |
| 99 | * we still send an event even if we can't open the file. this |
| 100 | * can happen when say tasks are gone and we try to open their |
| 101 | * /proc files or we try to open a WRONLY file like in sysfs |
| 102 | * we just send the errno to userspace since there isn't much |
| 103 | * else we can do. |
| 104 | */ |
| 105 | put_unused_fd(client_fd); |
| 106 | client_fd = PTR_ERR(new_file); |
| 107 | } else { |
Al Viro | 352e3b2 | 2012-08-19 12:30:45 -0400 | [diff] [blame] | 108 | *file = new_file; |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 109 | } |
| 110 | |
Andreas Gruenbacher | 22aa425 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 111 | return client_fd; |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 112 | } |
| 113 | |
Eric Paris | ecf6f5e | 2010-11-08 18:08:14 -0500 | [diff] [blame] | 114 | static int fill_event_metadata(struct fsnotify_group *group, |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 115 | struct fanotify_event_metadata *metadata, |
| 116 | struct fsnotify_event *fsn_event, |
| 117 | struct file **file) |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 118 | { |
Lino Sanfilippo | fdbf3ce | 2010-11-24 18:26:04 +0100 | [diff] [blame] | 119 | int ret = 0; |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 120 | struct fanotify_event_info *event; |
Lino Sanfilippo | fdbf3ce | 2010-11-24 18:26:04 +0100 | [diff] [blame] | 121 | |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 122 | pr_debug("%s: group=%p metadata=%p event=%p\n", __func__, |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 123 | group, metadata, fsn_event); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 124 | |
Al Viro | 352e3b2 | 2012-08-19 12:30:45 -0400 | [diff] [blame] | 125 | *file = NULL; |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 126 | event = container_of(fsn_event, struct fanotify_event_info, fse); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 127 | metadata->event_len = FAN_EVENT_METADATA_LEN; |
Eric Paris | 7d13162 | 2010-12-07 15:27:57 -0500 | [diff] [blame] | 128 | metadata->metadata_len = FAN_EVENT_METADATA_LEN; |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 129 | metadata->vers = FANOTIFY_METADATA_VERSION; |
Dan Carpenter | de1e0c4 | 2013-07-08 15:59:40 -0700 | [diff] [blame] | 130 | metadata->reserved = 0; |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 131 | metadata->mask = fsn_event->mask & FAN_ALL_OUTGOING_EVENTS; |
Andreas Gruenbacher | 32c3263 | 2009-12-17 21:24:27 -0500 | [diff] [blame] | 132 | metadata->pid = pid_vnr(event->tgid); |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 133 | if (unlikely(fsn_event->mask & FAN_Q_OVERFLOW)) |
Lino Sanfilippo | fdbf3ce | 2010-11-24 18:26:04 +0100 | [diff] [blame] | 134 | metadata->fd = FAN_NOFD; |
| 135 | else { |
Al Viro | 352e3b2 | 2012-08-19 12:30:45 -0400 | [diff] [blame] | 136 | metadata->fd = create_fd(group, event, file); |
Lino Sanfilippo | fdbf3ce | 2010-11-24 18:26:04 +0100 | [diff] [blame] | 137 | if (metadata->fd < 0) |
| 138 | ret = metadata->fd; |
| 139 | } |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 140 | |
Lino Sanfilippo | fdbf3ce | 2010-11-24 18:26:04 +0100 | [diff] [blame] | 141 | return ret; |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 142 | } |
| 143 | |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 144 | #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 145 | static struct fanotify_perm_event_info *dequeue_event( |
| 146 | struct fsnotify_group *group, int fd) |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 147 | { |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 148 | struct fanotify_perm_event_info *event, *return_e = NULL; |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 149 | |
Jan Kara | 073f655 | 2016-10-07 16:56:55 -0700 | [diff] [blame] | 150 | spin_lock(&group->notification_lock); |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 151 | list_for_each_entry(event, &group->fanotify_data.access_list, |
| 152 | fae.fse.list) { |
| 153 | if (event->fd != fd) |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 154 | continue; |
| 155 | |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 156 | list_del_init(&event->fae.fse.list); |
| 157 | return_e = event; |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 158 | break; |
| 159 | } |
Jan Kara | 073f655 | 2016-10-07 16:56:55 -0700 | [diff] [blame] | 160 | spin_unlock(&group->notification_lock); |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 161 | |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 162 | pr_debug("%s: found return_re=%p\n", __func__, return_e); |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 163 | |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 164 | return return_e; |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 165 | } |
| 166 | |
| 167 | static int process_access_response(struct fsnotify_group *group, |
| 168 | struct fanotify_response *response_struct) |
| 169 | { |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 170 | struct fanotify_perm_event_info *event; |
| 171 | int fd = response_struct->fd; |
| 172 | int response = response_struct->response; |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 173 | |
| 174 | pr_debug("%s: group=%p fd=%d response=%d\n", __func__, group, |
| 175 | fd, response); |
| 176 | /* |
| 177 | * make sure the response is valid, if invalid we do nothing and either |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 178 | * userspace can send a valid response or we will clean it up after the |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 179 | * timeout |
| 180 | */ |
| 181 | switch (response) { |
| 182 | case FAN_ALLOW: |
| 183 | case FAN_DENY: |
| 184 | break; |
| 185 | default: |
| 186 | return -EINVAL; |
| 187 | } |
| 188 | |
| 189 | if (fd < 0) |
| 190 | return -EINVAL; |
| 191 | |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 192 | event = dequeue_event(group, fd); |
| 193 | if (!event) |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 194 | return -ENOENT; |
| 195 | |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 196 | event->response = response; |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 197 | wake_up(&group->fanotify_data.access_waitq); |
| 198 | |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 199 | return 0; |
| 200 | } |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 201 | #endif |
| 202 | |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 203 | static ssize_t copy_event_to_user(struct fsnotify_group *group, |
| 204 | struct fsnotify_event *event, |
| 205 | char __user *buf) |
| 206 | { |
| 207 | struct fanotify_event_metadata fanotify_event_metadata; |
Al Viro | 352e3b2 | 2012-08-19 12:30:45 -0400 | [diff] [blame] | 208 | struct file *f; |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 209 | int fd, ret; |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 210 | |
| 211 | pr_debug("%s: group=%p event=%p\n", __func__, group, event); |
| 212 | |
Al Viro | 352e3b2 | 2012-08-19 12:30:45 -0400 | [diff] [blame] | 213 | ret = fill_event_metadata(group, &fanotify_event_metadata, event, &f); |
Eric Paris | ecf6f5e | 2010-11-08 18:08:14 -0500 | [diff] [blame] | 214 | if (ret < 0) |
Jan Kara | d507816 | 2014-04-03 14:46:36 -0700 | [diff] [blame] | 215 | return ret; |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 216 | |
Lino Sanfilippo | fdbf3ce | 2010-11-24 18:26:04 +0100 | [diff] [blame] | 217 | fd = fanotify_event_metadata.fd; |
Al Viro | 352e3b2 | 2012-08-19 12:30:45 -0400 | [diff] [blame] | 218 | ret = -EFAULT; |
| 219 | if (copy_to_user(buf, &fanotify_event_metadata, |
| 220 | fanotify_event_metadata.event_len)) |
| 221 | goto out_close_fd; |
| 222 | |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 223 | #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS |
Jan Kara | d507816 | 2014-04-03 14:46:36 -0700 | [diff] [blame] | 224 | if (event->mask & FAN_ALL_PERM_EVENTS) |
| 225 | FANOTIFY_PE(event)->fd = fd; |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 226 | #endif |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 227 | |
Al Viro | 3587b1b | 2012-11-18 19:19:00 +0000 | [diff] [blame] | 228 | if (fd != FAN_NOFD) |
| 229 | fd_install(fd, f); |
Eric Paris | 7d13162 | 2010-12-07 15:27:57 -0500 | [diff] [blame] | 230 | return fanotify_event_metadata.event_len; |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 231 | |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 232 | out_close_fd: |
Al Viro | 352e3b2 | 2012-08-19 12:30:45 -0400 | [diff] [blame] | 233 | if (fd != FAN_NOFD) { |
| 234 | put_unused_fd(fd); |
| 235 | fput(f); |
| 236 | } |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 237 | return ret; |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 238 | } |
| 239 | |
| 240 | /* intofiy userspace file descriptor functions */ |
| 241 | static unsigned int fanotify_poll(struct file *file, poll_table *wait) |
| 242 | { |
| 243 | struct fsnotify_group *group = file->private_data; |
| 244 | int ret = 0; |
| 245 | |
| 246 | poll_wait(file, &group->notification_waitq, wait); |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 247 | spin_lock(&group->notification_lock); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 248 | if (!fsnotify_notify_queue_is_empty(group)) |
| 249 | ret = POLLIN | POLLRDNORM; |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 250 | spin_unlock(&group->notification_lock); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 251 | |
| 252 | return ret; |
| 253 | } |
| 254 | |
| 255 | static ssize_t fanotify_read(struct file *file, char __user *buf, |
| 256 | size_t count, loff_t *pos) |
| 257 | { |
| 258 | struct fsnotify_group *group; |
| 259 | struct fsnotify_event *kevent; |
| 260 | char __user *start; |
| 261 | int ret; |
Peter Zijlstra | 536ebe9ca | 2014-12-16 16:28:38 +0100 | [diff] [blame] | 262 | DEFINE_WAIT_FUNC(wait, woken_wake_function); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 263 | |
| 264 | start = buf; |
| 265 | group = file->private_data; |
| 266 | |
| 267 | pr_debug("%s: group=%p\n", __func__, group); |
| 268 | |
Peter Zijlstra | 536ebe9ca | 2014-12-16 16:28:38 +0100 | [diff] [blame] | 269 | add_wait_queue(&group->notification_waitq, &wait); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 270 | while (1) { |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 271 | spin_lock(&group->notification_lock); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 272 | kevent = get_one_event(group, count); |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 273 | spin_unlock(&group->notification_lock); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 274 | |
Jan Kara | d8aaab4 | 2014-04-03 14:46:35 -0700 | [diff] [blame] | 275 | if (IS_ERR(kevent)) { |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 276 | ret = PTR_ERR(kevent); |
Jan Kara | d8aaab4 | 2014-04-03 14:46:35 -0700 | [diff] [blame] | 277 | break; |
| 278 | } |
| 279 | |
| 280 | if (!kevent) { |
| 281 | ret = -EAGAIN; |
| 282 | if (file->f_flags & O_NONBLOCK) |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 283 | break; |
Jan Kara | d8aaab4 | 2014-04-03 14:46:35 -0700 | [diff] [blame] | 284 | |
| 285 | ret = -ERESTARTSYS; |
| 286 | if (signal_pending(current)) |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 287 | break; |
Jan Kara | d8aaab4 | 2014-04-03 14:46:35 -0700 | [diff] [blame] | 288 | |
| 289 | if (start != buf) |
| 290 | break; |
Peter Zijlstra | 536ebe9ca | 2014-12-16 16:28:38 +0100 | [diff] [blame] | 291 | |
| 292 | wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 293 | continue; |
| 294 | } |
| 295 | |
Jan Kara | d8aaab4 | 2014-04-03 14:46:35 -0700 | [diff] [blame] | 296 | ret = copy_event_to_user(group, kevent, buf); |
Amir Goldstein | cc0f994 | 2017-04-25 14:29:35 +0300 | [diff] [blame] | 297 | if (unlikely(ret == -EOPENSTALE)) { |
| 298 | /* |
| 299 | * We cannot report events with stale fd so drop it. |
| 300 | * Setting ret to 0 will continue the event loop and |
| 301 | * do the right thing if there are no more events to |
| 302 | * read (i.e. return bytes read, -EAGAIN or wait). |
| 303 | */ |
| 304 | ret = 0; |
| 305 | } |
| 306 | |
Jan Kara | d8aaab4 | 2014-04-03 14:46:35 -0700 | [diff] [blame] | 307 | /* |
| 308 | * Permission events get queued to wait for response. Other |
| 309 | * events can be destroyed now. |
| 310 | */ |
Jan Kara | d507816 | 2014-04-03 14:46:36 -0700 | [diff] [blame] | 311 | if (!(kevent->mask & FAN_ALL_PERM_EVENTS)) { |
Jan Kara | d8aaab4 | 2014-04-03 14:46:35 -0700 | [diff] [blame] | 312 | fsnotify_destroy_event(group, kevent); |
Jan Kara | d507816 | 2014-04-03 14:46:36 -0700 | [diff] [blame] | 313 | } else { |
| 314 | #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS |
Amir Goldstein | cc0f994 | 2017-04-25 14:29:35 +0300 | [diff] [blame] | 315 | if (ret <= 0) { |
Jan Kara | d507816 | 2014-04-03 14:46:36 -0700 | [diff] [blame] | 316 | FANOTIFY_PE(kevent)->response = FAN_DENY; |
| 317 | wake_up(&group->fanotify_data.access_waitq); |
Amir Goldstein | cc0f994 | 2017-04-25 14:29:35 +0300 | [diff] [blame] | 318 | } else { |
| 319 | spin_lock(&group->notification_lock); |
| 320 | list_add_tail(&kevent->list, |
| 321 | &group->fanotify_data.access_list); |
| 322 | spin_unlock(&group->notification_lock); |
Jan Kara | d507816 | 2014-04-03 14:46:36 -0700 | [diff] [blame] | 323 | } |
Jan Kara | d507816 | 2014-04-03 14:46:36 -0700 | [diff] [blame] | 324 | #endif |
| 325 | } |
Amir Goldstein | cc0f994 | 2017-04-25 14:29:35 +0300 | [diff] [blame] | 326 | if (ret < 0) |
| 327 | break; |
Jan Kara | d8aaab4 | 2014-04-03 14:46:35 -0700 | [diff] [blame] | 328 | buf += ret; |
| 329 | count -= ret; |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 330 | } |
Peter Zijlstra | 536ebe9ca | 2014-12-16 16:28:38 +0100 | [diff] [blame] | 331 | remove_wait_queue(&group->notification_waitq, &wait); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 332 | |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 333 | if (start != buf && ret != -EFAULT) |
| 334 | ret = buf - start; |
| 335 | return ret; |
| 336 | } |
| 337 | |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 338 | static ssize_t fanotify_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) |
| 339 | { |
| 340 | #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS |
| 341 | struct fanotify_response response = { .fd = -1, .response = -1 }; |
| 342 | struct fsnotify_group *group; |
| 343 | int ret; |
| 344 | |
| 345 | group = file->private_data; |
| 346 | |
| 347 | if (count > sizeof(response)) |
| 348 | count = sizeof(response); |
| 349 | |
| 350 | pr_debug("%s: group=%p count=%zu\n", __func__, group, count); |
| 351 | |
| 352 | if (copy_from_user(&response, buf, count)) |
| 353 | return -EFAULT; |
| 354 | |
| 355 | ret = process_access_response(group, &response); |
| 356 | if (ret < 0) |
| 357 | count = ret; |
| 358 | |
| 359 | return count; |
| 360 | #else |
| 361 | return -EINVAL; |
| 362 | #endif |
| 363 | } |
| 364 | |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 365 | static int fanotify_release(struct inode *ignored, struct file *file) |
| 366 | { |
| 367 | struct fsnotify_group *group = file->private_data; |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 368 | |
Eric Paris | 2eebf58 | 2010-08-18 12:25:50 -0400 | [diff] [blame] | 369 | #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 370 | struct fanotify_perm_event_info *event, *next; |
Jan Kara | 96d4101 | 2016-09-19 14:44:30 -0700 | [diff] [blame] | 371 | struct fsnotify_event *fsn_event; |
Andrew Morton | 19ba54f | 2010-10-28 17:21:59 -0400 | [diff] [blame] | 372 | |
Jan Kara | 5838d44 | 2014-08-06 16:03:28 -0700 | [diff] [blame] | 373 | /* |
Jan Kara | 96d4101 | 2016-09-19 14:44:30 -0700 | [diff] [blame] | 374 | * Stop new events from arriving in the notification queue. since |
| 375 | * userspace cannot use fanotify fd anymore, no event can enter or |
| 376 | * leave access_list by now either. |
| 377 | */ |
| 378 | fsnotify_group_stop_queueing(group); |
| 379 | |
| 380 | /* |
| 381 | * Process all permission events on access_list and notification queue |
| 382 | * and simulate reply from userspace. |
Jan Kara | 5838d44 | 2014-08-06 16:03:28 -0700 | [diff] [blame] | 383 | */ |
Jan Kara | 073f655 | 2016-10-07 16:56:55 -0700 | [diff] [blame] | 384 | spin_lock(&group->notification_lock); |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 385 | list_for_each_entry_safe(event, next, &group->fanotify_data.access_list, |
| 386 | fae.fse.list) { |
| 387 | pr_debug("%s: found group=%p event=%p\n", __func__, group, |
| 388 | event); |
Eric Paris | 2eebf58 | 2010-08-18 12:25:50 -0400 | [diff] [blame] | 389 | |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 390 | list_del_init(&event->fae.fse.list); |
| 391 | event->response = FAN_ALLOW; |
Eric Paris | 2eebf58 | 2010-08-18 12:25:50 -0400 | [diff] [blame] | 392 | } |
Eric Paris | 2eebf58 | 2010-08-18 12:25:50 -0400 | [diff] [blame] | 393 | |
Jan Kara | 5838d44 | 2014-08-06 16:03:28 -0700 | [diff] [blame] | 394 | /* |
Jan Kara | 96d4101 | 2016-09-19 14:44:30 -0700 | [diff] [blame] | 395 | * Destroy all non-permission events. For permission events just |
| 396 | * dequeue them and set the response. They will be freed once the |
| 397 | * response is consumed and fanotify_get_response() returns. |
Jan Kara | 5838d44 | 2014-08-06 16:03:28 -0700 | [diff] [blame] | 398 | */ |
Jan Kara | 96d4101 | 2016-09-19 14:44:30 -0700 | [diff] [blame] | 399 | while (!fsnotify_notify_queue_is_empty(group)) { |
| 400 | fsn_event = fsnotify_remove_first_event(group); |
Jan Kara | 1404ff3 | 2016-10-07 16:56:49 -0700 | [diff] [blame] | 401 | if (!(fsn_event->mask & FAN_ALL_PERM_EVENTS)) { |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 402 | spin_unlock(&group->notification_lock); |
Jan Kara | 96d4101 | 2016-09-19 14:44:30 -0700 | [diff] [blame] | 403 | fsnotify_destroy_event(group, fsn_event); |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 404 | spin_lock(&group->notification_lock); |
Jan Kara | 1404ff3 | 2016-10-07 16:56:49 -0700 | [diff] [blame] | 405 | } else |
Jan Kara | 96d4101 | 2016-09-19 14:44:30 -0700 | [diff] [blame] | 406 | FANOTIFY_PE(fsn_event)->response = FAN_ALLOW; |
| 407 | } |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 408 | spin_unlock(&group->notification_lock); |
Jan Kara | 96d4101 | 2016-09-19 14:44:30 -0700 | [diff] [blame] | 409 | |
| 410 | /* Response for all permission events it set, wakeup waiters */ |
Eric Paris | 2eebf58 | 2010-08-18 12:25:50 -0400 | [diff] [blame] | 411 | wake_up(&group->fanotify_data.access_waitq); |
| 412 | #endif |
Eric Paris | 0a6b6bd | 2011-10-14 17:43:39 -0400 | [diff] [blame] | 413 | |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 414 | /* matches the fanotify_init->fsnotify_alloc_group */ |
Lino Sanfilippo | d8153d4 | 2011-06-14 17:29:45 +0200 | [diff] [blame] | 415 | fsnotify_destroy_group(group); |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 416 | |
| 417 | return 0; |
| 418 | } |
| 419 | |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 420 | static long fanotify_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
| 421 | { |
| 422 | struct fsnotify_group *group; |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 423 | struct fsnotify_event *fsn_event; |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 424 | void __user *p; |
| 425 | int ret = -ENOTTY; |
| 426 | size_t send_len = 0; |
| 427 | |
| 428 | group = file->private_data; |
| 429 | |
| 430 | p = (void __user *) arg; |
| 431 | |
| 432 | switch (cmd) { |
| 433 | case FIONREAD: |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 434 | spin_lock(&group->notification_lock); |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 435 | list_for_each_entry(fsn_event, &group->notification_list, list) |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 436 | send_len += FAN_EVENT_METADATA_LEN; |
Jan Kara | c21dbe2 | 2016-10-07 16:56:52 -0700 | [diff] [blame] | 437 | spin_unlock(&group->notification_lock); |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 438 | ret = put_user(send_len, (int __user *) p); |
| 439 | break; |
| 440 | } |
| 441 | |
| 442 | return ret; |
| 443 | } |
| 444 | |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 445 | static const struct file_operations fanotify_fops = { |
Cyrill Gorcunov | be77196 | 2012-12-17 16:05:12 -0800 | [diff] [blame] | 446 | .show_fdinfo = fanotify_show_fdinfo, |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 447 | .poll = fanotify_poll, |
| 448 | .read = fanotify_read, |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 449 | .write = fanotify_write, |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 450 | .fasync = NULL, |
| 451 | .release = fanotify_release, |
Eric Paris | a1014f1 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 452 | .unlocked_ioctl = fanotify_ioctl, |
| 453 | .compat_ioctl = fanotify_ioctl, |
Arnd Bergmann | 6038f37 | 2010-08-15 18:52:59 +0200 | [diff] [blame] | 454 | .llseek = noop_llseek, |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 455 | }; |
| 456 | |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 457 | static void fanotify_free_mark(struct fsnotify_mark *fsn_mark) |
| 458 | { |
| 459 | kmem_cache_free(fanotify_mark_cache, fsn_mark); |
| 460 | } |
| 461 | |
| 462 | static int fanotify_find_path(int dfd, const char __user *filename, |
| 463 | struct path *path, unsigned int flags) |
| 464 | { |
| 465 | int ret; |
| 466 | |
| 467 | pr_debug("%s: dfd=%d filename=%p flags=%x\n", __func__, |
| 468 | dfd, filename, flags); |
| 469 | |
| 470 | if (filename == NULL) { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 471 | struct fd f = fdget(dfd); |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 472 | |
| 473 | ret = -EBADF; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 474 | if (!f.file) |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 475 | goto out; |
| 476 | |
| 477 | ret = -ENOTDIR; |
| 478 | if ((flags & FAN_MARK_ONLYDIR) && |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 479 | !(S_ISDIR(file_inode(f.file)->i_mode))) { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 480 | fdput(f); |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 481 | goto out; |
| 482 | } |
| 483 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 484 | *path = f.file->f_path; |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 485 | path_get(path); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 486 | fdput(f); |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 487 | } else { |
| 488 | unsigned int lookup_flags = 0; |
| 489 | |
| 490 | if (!(flags & FAN_MARK_DONT_FOLLOW)) |
| 491 | lookup_flags |= LOOKUP_FOLLOW; |
| 492 | if (flags & FAN_MARK_ONLYDIR) |
| 493 | lookup_flags |= LOOKUP_DIRECTORY; |
| 494 | |
| 495 | ret = user_path_at(dfd, filename, lookup_flags, path); |
| 496 | if (ret) |
| 497 | goto out; |
| 498 | } |
| 499 | |
| 500 | /* you can only watch an inode if you have read permissions on it */ |
| 501 | ret = inode_permission(path->dentry->d_inode, MAY_READ); |
| 502 | if (ret) |
| 503 | path_put(path); |
| 504 | out: |
| 505 | return ret; |
| 506 | } |
| 507 | |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 508 | static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark, |
| 509 | __u32 mask, |
Lino Sanfilippo | 6dfbd14 | 2011-06-14 17:29:49 +0200 | [diff] [blame] | 510 | unsigned int flags, |
| 511 | int *destroy) |
Andreas Gruenbacher | 088b09b | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 512 | { |
Lino Sanfilippo | d2c1874 | 2015-02-10 14:08:24 -0800 | [diff] [blame] | 513 | __u32 oldmask = 0; |
Andreas Gruenbacher | 088b09b | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 514 | |
| 515 | spin_lock(&fsn_mark->lock); |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 516 | if (!(flags & FAN_MARK_IGNORED_MASK)) { |
Lino Sanfilippo | 66ba93c | 2015-02-10 14:08:27 -0800 | [diff] [blame] | 517 | __u32 tmask = fsn_mark->mask & ~mask; |
| 518 | |
| 519 | if (flags & FAN_MARK_ONDIR) |
| 520 | tmask &= ~FAN_ONDIR; |
| 521 | |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 522 | oldmask = fsn_mark->mask; |
Lino Sanfilippo | 66ba93c | 2015-02-10 14:08:27 -0800 | [diff] [blame] | 523 | fsnotify_set_mark_mask_locked(fsn_mark, tmask); |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 524 | } else { |
Lino Sanfilippo | d2c1874 | 2015-02-10 14:08:24 -0800 | [diff] [blame] | 525 | __u32 tmask = fsn_mark->ignored_mask & ~mask; |
Lino Sanfilippo | 66ba93c | 2015-02-10 14:08:27 -0800 | [diff] [blame] | 526 | if (flags & FAN_MARK_ONDIR) |
| 527 | tmask &= ~FAN_ONDIR; |
Lino Sanfilippo | d2c1874 | 2015-02-10 14:08:24 -0800 | [diff] [blame] | 528 | |
| 529 | fsnotify_set_mark_ignored_mask_locked(fsn_mark, tmask); |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 530 | } |
Lino Sanfilippo | a118449 | 2015-02-10 14:08:21 -0800 | [diff] [blame] | 531 | *destroy = !(fsn_mark->mask | fsn_mark->ignored_mask); |
Andreas Gruenbacher | 088b09b | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 532 | spin_unlock(&fsn_mark->lock); |
| 533 | |
Andreas Gruenbacher | 088b09b | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 534 | return mask & oldmask; |
| 535 | } |
| 536 | |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 537 | static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group, |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 538 | struct vfsmount *mnt, __u32 mask, |
| 539 | unsigned int flags) |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 540 | { |
| 541 | struct fsnotify_mark *fsn_mark = NULL; |
Andreas Gruenbacher | 088b09b | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 542 | __u32 removed; |
Lino Sanfilippo | 6dfbd14 | 2011-06-14 17:29:49 +0200 | [diff] [blame] | 543 | int destroy_mark; |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 544 | |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 545 | mutex_lock(&group->mark_mutex); |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 546 | fsn_mark = fsnotify_find_vfsmount_mark(group, mnt); |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 547 | if (!fsn_mark) { |
| 548 | mutex_unlock(&group->mark_mutex); |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 549 | return -ENOENT; |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 550 | } |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 551 | |
Lino Sanfilippo | 6dfbd14 | 2011-06-14 17:29:49 +0200 | [diff] [blame] | 552 | removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags, |
| 553 | &destroy_mark); |
| 554 | if (destroy_mark) |
Jan Kara | 4712e722 | 2015-09-04 15:43:12 -0700 | [diff] [blame] | 555 | fsnotify_detach_mark(fsn_mark); |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 556 | mutex_unlock(&group->mark_mutex); |
Jan Kara | 4712e722 | 2015-09-04 15:43:12 -0700 | [diff] [blame] | 557 | if (destroy_mark) |
| 558 | fsnotify_free_mark(fsn_mark); |
Lino Sanfilippo | 6dfbd14 | 2011-06-14 17:29:49 +0200 | [diff] [blame] | 559 | |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 560 | fsnotify_put_mark(fsn_mark); |
Al Viro | c63181e | 2011-11-25 02:35:16 -0500 | [diff] [blame] | 561 | if (removed & real_mount(mnt)->mnt_fsnotify_mask) |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 562 | fsnotify_recalc_vfsmount_mask(mnt); |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 563 | |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 564 | return 0; |
| 565 | } |
| 566 | |
| 567 | static int fanotify_remove_inode_mark(struct fsnotify_group *group, |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 568 | struct inode *inode, __u32 mask, |
| 569 | unsigned int flags) |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 570 | { |
| 571 | struct fsnotify_mark *fsn_mark = NULL; |
| 572 | __u32 removed; |
Lino Sanfilippo | 6dfbd14 | 2011-06-14 17:29:49 +0200 | [diff] [blame] | 573 | int destroy_mark; |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 574 | |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 575 | mutex_lock(&group->mark_mutex); |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 576 | fsn_mark = fsnotify_find_inode_mark(group, inode); |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 577 | if (!fsn_mark) { |
| 578 | mutex_unlock(&group->mark_mutex); |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 579 | return -ENOENT; |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 580 | } |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 581 | |
Lino Sanfilippo | 6dfbd14 | 2011-06-14 17:29:49 +0200 | [diff] [blame] | 582 | removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags, |
| 583 | &destroy_mark); |
| 584 | if (destroy_mark) |
Jan Kara | 4712e722 | 2015-09-04 15:43:12 -0700 | [diff] [blame] | 585 | fsnotify_detach_mark(fsn_mark); |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 586 | mutex_unlock(&group->mark_mutex); |
Jan Kara | 4712e722 | 2015-09-04 15:43:12 -0700 | [diff] [blame] | 587 | if (destroy_mark) |
| 588 | fsnotify_free_mark(fsn_mark); |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 589 | |
Eric Paris | 5444e29 | 2009-12-17 21:24:27 -0500 | [diff] [blame] | 590 | /* matches the fsnotify_find_inode_mark() */ |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 591 | fsnotify_put_mark(fsn_mark); |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 592 | if (removed & inode->i_fsnotify_mask) |
| 593 | fsnotify_recalc_inode_mask(inode); |
Andreas Gruenbacher | 088b09b | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 594 | |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 595 | return 0; |
| 596 | } |
| 597 | |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 598 | static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark, |
| 599 | __u32 mask, |
| 600 | unsigned int flags) |
Andreas Gruenbacher | 912ee3946 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 601 | { |
Eric Paris | 192ca4d | 2010-10-28 17:21:59 -0400 | [diff] [blame] | 602 | __u32 oldmask = -1; |
Andreas Gruenbacher | 912ee3946 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 603 | |
| 604 | spin_lock(&fsn_mark->lock); |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 605 | if (!(flags & FAN_MARK_IGNORED_MASK)) { |
Lino Sanfilippo | 66ba93c | 2015-02-10 14:08:27 -0800 | [diff] [blame] | 606 | __u32 tmask = fsn_mark->mask | mask; |
| 607 | |
| 608 | if (flags & FAN_MARK_ONDIR) |
| 609 | tmask |= FAN_ONDIR; |
| 610 | |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 611 | oldmask = fsn_mark->mask; |
Lino Sanfilippo | 66ba93c | 2015-02-10 14:08:27 -0800 | [diff] [blame] | 612 | fsnotify_set_mark_mask_locked(fsn_mark, tmask); |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 613 | } else { |
Eric Paris | 192ca4d | 2010-10-28 17:21:59 -0400 | [diff] [blame] | 614 | __u32 tmask = fsn_mark->ignored_mask | mask; |
Lino Sanfilippo | 66ba93c | 2015-02-10 14:08:27 -0800 | [diff] [blame] | 615 | if (flags & FAN_MARK_ONDIR) |
| 616 | tmask |= FAN_ONDIR; |
| 617 | |
Eric Paris | 192ca4d | 2010-10-28 17:21:59 -0400 | [diff] [blame] | 618 | fsnotify_set_mark_ignored_mask_locked(fsn_mark, tmask); |
Eric Paris | c9778a9 | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 619 | if (flags & FAN_MARK_IGNORED_SURV_MODIFY) |
| 620 | fsn_mark->flags |= FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY; |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 621 | } |
Andreas Gruenbacher | 912ee3946 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 622 | spin_unlock(&fsn_mark->lock); |
| 623 | |
| 624 | return mask & ~oldmask; |
| 625 | } |
| 626 | |
Lino Sanfilippo | 5e9c070c | 2013-07-08 15:59:43 -0700 | [diff] [blame] | 627 | static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, |
| 628 | struct inode *inode, |
| 629 | struct vfsmount *mnt) |
| 630 | { |
| 631 | struct fsnotify_mark *mark; |
| 632 | int ret; |
| 633 | |
| 634 | if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks) |
| 635 | return ERR_PTR(-ENOSPC); |
| 636 | |
| 637 | mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL); |
| 638 | if (!mark) |
| 639 | return ERR_PTR(-ENOMEM); |
| 640 | |
| 641 | fsnotify_init_mark(mark, fanotify_free_mark); |
| 642 | ret = fsnotify_add_mark_locked(mark, group, inode, mnt, 0); |
| 643 | if (ret) { |
| 644 | fsnotify_put_mark(mark); |
| 645 | return ERR_PTR(ret); |
| 646 | } |
| 647 | |
| 648 | return mark; |
| 649 | } |
| 650 | |
| 651 | |
Andreas Gruenbacher | 52202df | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 652 | static int fanotify_add_vfsmount_mark(struct fsnotify_group *group, |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 653 | struct vfsmount *mnt, __u32 mask, |
| 654 | unsigned int flags) |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 655 | { |
| 656 | struct fsnotify_mark *fsn_mark; |
Andreas Gruenbacher | 912ee3946 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 657 | __u32 added; |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 658 | |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 659 | mutex_lock(&group->mark_mutex); |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 660 | fsn_mark = fsnotify_find_vfsmount_mark(group, mnt); |
| 661 | if (!fsn_mark) { |
Lino Sanfilippo | 5e9c070c | 2013-07-08 15:59:43 -0700 | [diff] [blame] | 662 | fsn_mark = fanotify_add_new_mark(group, NULL, mnt); |
| 663 | if (IS_ERR(fsn_mark)) { |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 664 | mutex_unlock(&group->mark_mutex); |
Lino Sanfilippo | 5e9c070c | 2013-07-08 15:59:43 -0700 | [diff] [blame] | 665 | return PTR_ERR(fsn_mark); |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 666 | } |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 667 | } |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 668 | added = fanotify_mark_add_to_mask(fsn_mark, mask, flags); |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 669 | mutex_unlock(&group->mark_mutex); |
Lino Sanfilippo | fa218ab | 2010-11-09 18:18:16 +0100 | [diff] [blame] | 670 | |
Al Viro | c63181e | 2011-11-25 02:35:16 -0500 | [diff] [blame] | 671 | if (added & ~real_mount(mnt)->mnt_fsnotify_mask) |
Eric Paris | 43709a2 | 2010-07-28 10:18:39 -0400 | [diff] [blame] | 672 | fsnotify_recalc_vfsmount_mask(mnt); |
Lino Sanfilippo | 5e9c070c | 2013-07-08 15:59:43 -0700 | [diff] [blame] | 673 | |
Lino Sanfilippo | fa218ab | 2010-11-09 18:18:16 +0100 | [diff] [blame] | 674 | fsnotify_put_mark(fsn_mark); |
Lino Sanfilippo | 5e9c070c | 2013-07-08 15:59:43 -0700 | [diff] [blame] | 675 | return 0; |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 676 | } |
| 677 | |
Andreas Gruenbacher | 52202df | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 678 | static int fanotify_add_inode_mark(struct fsnotify_group *group, |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 679 | struct inode *inode, __u32 mask, |
| 680 | unsigned int flags) |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 681 | { |
| 682 | struct fsnotify_mark *fsn_mark; |
Andreas Gruenbacher | 912ee3946 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 683 | __u32 added; |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 684 | |
| 685 | pr_debug("%s: group=%p inode=%p\n", __func__, group, inode); |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 686 | |
Eric Paris | 5322a59 | 2010-10-28 17:21:57 -0400 | [diff] [blame] | 687 | /* |
| 688 | * If some other task has this inode open for write we should not add |
| 689 | * an ignored mark, unless that ignored mark is supposed to survive |
| 690 | * modification changes anyway. |
| 691 | */ |
| 692 | if ((flags & FAN_MARK_IGNORED_MASK) && |
| 693 | !(flags & FAN_MARK_IGNORED_SURV_MODIFY) && |
| 694 | (atomic_read(&inode->i_writecount) > 0)) |
| 695 | return 0; |
| 696 | |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 697 | mutex_lock(&group->mark_mutex); |
Eric Paris | 5444e29 | 2009-12-17 21:24:27 -0500 | [diff] [blame] | 698 | fsn_mark = fsnotify_find_inode_mark(group, inode); |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 699 | if (!fsn_mark) { |
Lino Sanfilippo | 5e9c070c | 2013-07-08 15:59:43 -0700 | [diff] [blame] | 700 | fsn_mark = fanotify_add_new_mark(group, inode, NULL); |
| 701 | if (IS_ERR(fsn_mark)) { |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 702 | mutex_unlock(&group->mark_mutex); |
Lino Sanfilippo | 5e9c070c | 2013-07-08 15:59:43 -0700 | [diff] [blame] | 703 | return PTR_ERR(fsn_mark); |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 704 | } |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 705 | } |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 706 | added = fanotify_mark_add_to_mask(fsn_mark, mask, flags); |
Lino Sanfilippo | 7b18527 | 2013-07-08 15:59:42 -0700 | [diff] [blame] | 707 | mutex_unlock(&group->mark_mutex); |
Lino Sanfilippo | fa218ab | 2010-11-09 18:18:16 +0100 | [diff] [blame] | 708 | |
Eric Paris | 43709a2 | 2010-07-28 10:18:39 -0400 | [diff] [blame] | 709 | if (added & ~inode->i_fsnotify_mask) |
| 710 | fsnotify_recalc_inode_mask(inode); |
Lino Sanfilippo | 5e9c070c | 2013-07-08 15:59:43 -0700 | [diff] [blame] | 711 | |
Lino Sanfilippo | fa218ab | 2010-11-09 18:18:16 +0100 | [diff] [blame] | 712 | fsnotify_put_mark(fsn_mark); |
Lino Sanfilippo | 5e9c070c | 2013-07-08 15:59:43 -0700 | [diff] [blame] | 713 | return 0; |
Eric Paris | 8882627 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 714 | } |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 715 | |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 716 | /* fanotify syscalls */ |
Eric Paris | 08ae893 | 2010-05-27 09:41:40 -0400 | [diff] [blame] | 717 | SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) |
Eric Paris | 11637e4 | 2009-12-17 21:24:25 -0500 | [diff] [blame] | 718 | { |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 719 | struct fsnotify_group *group; |
| 720 | int f_flags, fd; |
Eric Paris | 4afeff8 | 2010-10-28 17:21:58 -0400 | [diff] [blame] | 721 | struct user_struct *user; |
Jan Kara | ff57cd5 | 2014-02-21 19:14:11 +0100 | [diff] [blame] | 722 | struct fanotify_event_info *oevent; |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 723 | |
Eric Paris | 08ae893 | 2010-05-27 09:41:40 -0400 | [diff] [blame] | 724 | pr_debug("%s: flags=%d event_f_flags=%d\n", |
| 725 | __func__, flags, event_f_flags); |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 726 | |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 727 | if (!capable(CAP_SYS_ADMIN)) |
Andreas Gruenbacher | a2f13ad | 2010-08-24 12:58:54 +0200 | [diff] [blame] | 728 | return -EPERM; |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 729 | |
| 730 | if (flags & ~FAN_ALL_INIT_FLAGS) |
| 731 | return -EINVAL; |
| 732 | |
Heinrich Schuchardt | 48149e9 | 2014-06-04 16:05:44 -0700 | [diff] [blame] | 733 | if (event_f_flags & ~FANOTIFY_INIT_ALL_EVENT_F_BITS) |
| 734 | return -EINVAL; |
| 735 | |
| 736 | switch (event_f_flags & O_ACCMODE) { |
| 737 | case O_RDONLY: |
| 738 | case O_RDWR: |
| 739 | case O_WRONLY: |
| 740 | break; |
| 741 | default: |
| 742 | return -EINVAL; |
| 743 | } |
| 744 | |
Eric Paris | 4afeff8 | 2010-10-28 17:21:58 -0400 | [diff] [blame] | 745 | user = get_current_user(); |
| 746 | if (atomic_read(&user->fanotify_listeners) > FANOTIFY_DEFAULT_MAX_LISTENERS) { |
| 747 | free_uid(user); |
| 748 | return -EMFILE; |
| 749 | } |
| 750 | |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 751 | f_flags = O_RDWR | FMODE_NONOTIFY; |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 752 | if (flags & FAN_CLOEXEC) |
| 753 | f_flags |= O_CLOEXEC; |
| 754 | if (flags & FAN_NONBLOCK) |
| 755 | f_flags |= O_NONBLOCK; |
| 756 | |
| 757 | /* fsnotify_alloc_group takes a ref. Dropped in fanotify_release */ |
| 758 | group = fsnotify_alloc_group(&fanotify_fsnotify_ops); |
Eric Paris | 2637919 | 2010-11-23 23:48:26 -0500 | [diff] [blame] | 759 | if (IS_ERR(group)) { |
| 760 | free_uid(user); |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 761 | return PTR_ERR(group); |
Eric Paris | 2637919 | 2010-11-23 23:48:26 -0500 | [diff] [blame] | 762 | } |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 763 | |
Eric Paris | 4afeff8 | 2010-10-28 17:21:58 -0400 | [diff] [blame] | 764 | group->fanotify_data.user = user; |
| 765 | atomic_inc(&user->fanotify_listeners); |
| 766 | |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 767 | oevent = fanotify_alloc_event(NULL, FS_Q_OVERFLOW, NULL); |
Jan Kara | ff57cd5 | 2014-02-21 19:14:11 +0100 | [diff] [blame] | 768 | if (unlikely(!oevent)) { |
| 769 | fd = -ENOMEM; |
| 770 | goto out_destroy_group; |
| 771 | } |
| 772 | group->overflow_event = &oevent->fse; |
Jan Kara | ff57cd5 | 2014-02-21 19:14:11 +0100 | [diff] [blame] | 773 | |
Will Woods | 1e2ee49 | 2014-05-06 12:50:10 -0700 | [diff] [blame] | 774 | if (force_o_largefile()) |
| 775 | event_f_flags |= O_LARGEFILE; |
Eric Paris | 80af258 | 2010-07-28 10:18:37 -0400 | [diff] [blame] | 776 | group->fanotify_data.f_flags = event_f_flags; |
Eric Paris | 9e66e42 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 777 | #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS |
Eric Paris | 9e66e42 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 778 | init_waitqueue_head(&group->fanotify_data.access_waitq); |
| 779 | INIT_LIST_HEAD(&group->fanotify_data.access_list); |
| 780 | #endif |
Eric Paris | 4231a23 | 2010-10-28 17:21:56 -0400 | [diff] [blame] | 781 | switch (flags & FAN_ALL_CLASS_BITS) { |
| 782 | case FAN_CLASS_NOTIF: |
| 783 | group->priority = FS_PRIO_0; |
| 784 | break; |
| 785 | case FAN_CLASS_CONTENT: |
| 786 | group->priority = FS_PRIO_1; |
| 787 | break; |
| 788 | case FAN_CLASS_PRE_CONTENT: |
| 789 | group->priority = FS_PRIO_2; |
| 790 | break; |
| 791 | default: |
| 792 | fd = -EINVAL; |
Lino Sanfilippo | d8153d4 | 2011-06-14 17:29:45 +0200 | [diff] [blame] | 793 | goto out_destroy_group; |
Eric Paris | 4231a23 | 2010-10-28 17:21:56 -0400 | [diff] [blame] | 794 | } |
Eric Paris | cb2d429 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 795 | |
Eric Paris | 5dd03f5 | 2010-10-28 17:21:57 -0400 | [diff] [blame] | 796 | if (flags & FAN_UNLIMITED_QUEUE) { |
| 797 | fd = -EPERM; |
| 798 | if (!capable(CAP_SYS_ADMIN)) |
Lino Sanfilippo | d8153d4 | 2011-06-14 17:29:45 +0200 | [diff] [blame] | 799 | goto out_destroy_group; |
Eric Paris | 5dd03f5 | 2010-10-28 17:21:57 -0400 | [diff] [blame] | 800 | group->max_events = UINT_MAX; |
| 801 | } else { |
| 802 | group->max_events = FANOTIFY_DEFAULT_MAX_EVENTS; |
| 803 | } |
Eric Paris | 2529a0d | 2010-10-28 17:21:57 -0400 | [diff] [blame] | 804 | |
Eric Paris | ac7e22d | 2010-10-28 17:21:58 -0400 | [diff] [blame] | 805 | if (flags & FAN_UNLIMITED_MARKS) { |
| 806 | fd = -EPERM; |
| 807 | if (!capable(CAP_SYS_ADMIN)) |
Lino Sanfilippo | d8153d4 | 2011-06-14 17:29:45 +0200 | [diff] [blame] | 808 | goto out_destroy_group; |
Eric Paris | ac7e22d | 2010-10-28 17:21:58 -0400 | [diff] [blame] | 809 | group->fanotify_data.max_marks = UINT_MAX; |
| 810 | } else { |
| 811 | group->fanotify_data.max_marks = FANOTIFY_DEFAULT_MAX_MARKS; |
| 812 | } |
Eric Paris | e7099d8 | 2010-10-28 17:21:57 -0400 | [diff] [blame] | 813 | |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 814 | fd = anon_inode_getfd("[fanotify]", &fanotify_fops, group, f_flags); |
| 815 | if (fd < 0) |
Lino Sanfilippo | d8153d4 | 2011-06-14 17:29:45 +0200 | [diff] [blame] | 816 | goto out_destroy_group; |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 817 | |
| 818 | return fd; |
| 819 | |
Lino Sanfilippo | d8153d4 | 2011-06-14 17:29:45 +0200 | [diff] [blame] | 820 | out_destroy_group: |
| 821 | fsnotify_destroy_group(group); |
Eric Paris | 52c923d | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 822 | return fd; |
Eric Paris | 11637e4 | 2009-12-17 21:24:25 -0500 | [diff] [blame] | 823 | } |
Eric Paris | bbaa416 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 824 | |
Al Viro | 4a0fd5b | 2013-01-21 15:16:58 -0500 | [diff] [blame] | 825 | SYSCALL_DEFINE5(fanotify_mark, int, fanotify_fd, unsigned int, flags, |
| 826 | __u64, mask, int, dfd, |
| 827 | const char __user *, pathname) |
Eric Paris | bbaa416 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 828 | { |
Eric Paris | 0ff21db | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 829 | struct inode *inode = NULL; |
| 830 | struct vfsmount *mnt = NULL; |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 831 | struct fsnotify_group *group; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 832 | struct fd f; |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 833 | struct path path; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 834 | int ret; |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 835 | |
| 836 | pr_debug("%s: fanotify_fd=%d flags=%x dfd=%d pathname=%p mask=%llx\n", |
| 837 | __func__, fanotify_fd, flags, dfd, pathname, mask); |
| 838 | |
| 839 | /* we only use the lower 32 bits as of right now. */ |
| 840 | if (mask & ((__u64)0xffffffff << 32)) |
| 841 | return -EINVAL; |
| 842 | |
Andreas Gruenbacher | 88380fe | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 843 | if (flags & ~FAN_ALL_MARK_FLAGS) |
| 844 | return -EINVAL; |
Eric Paris | 4d92604 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 845 | switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE | FAN_MARK_FLUSH)) { |
Lino Sanfilippo | 1734dee | 2010-11-22 18:46:33 +0100 | [diff] [blame] | 846 | case FAN_MARK_ADD: /* fallthrough */ |
Andreas Gruenbacher | 88380fe | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 847 | case FAN_MARK_REMOVE: |
Lino Sanfilippo | 1734dee | 2010-11-22 18:46:33 +0100 | [diff] [blame] | 848 | if (!mask) |
| 849 | return -EINVAL; |
Heinrich Schuchardt | cc299a9 | 2014-06-04 16:05:43 -0700 | [diff] [blame] | 850 | break; |
Eric Paris | 4d92604 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 851 | case FAN_MARK_FLUSH: |
Heinrich Schuchardt | cc299a9 | 2014-06-04 16:05:43 -0700 | [diff] [blame] | 852 | if (flags & ~(FAN_MARK_MOUNT | FAN_MARK_FLUSH)) |
| 853 | return -EINVAL; |
Andreas Gruenbacher | 88380fe | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 854 | break; |
| 855 | default: |
| 856 | return -EINVAL; |
| 857 | } |
Eric Paris | 8fcd652 | 2010-10-28 17:21:59 -0400 | [diff] [blame] | 858 | |
| 859 | if (mask & FAN_ONDIR) { |
| 860 | flags |= FAN_MARK_ONDIR; |
| 861 | mask &= ~FAN_ONDIR; |
| 862 | } |
| 863 | |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 864 | #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS |
| 865 | if (mask & ~(FAN_ALL_EVENTS | FAN_ALL_PERM_EVENTS | FAN_EVENT_ON_CHILD)) |
| 866 | #else |
Andreas Gruenbacher | 88380fe | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 867 | if (mask & ~(FAN_ALL_EVENTS | FAN_EVENT_ON_CHILD)) |
Eric Paris | b2d8790 | 2009-12-17 21:24:34 -0500 | [diff] [blame] | 868 | #endif |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 869 | return -EINVAL; |
| 870 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 871 | f = fdget(fanotify_fd); |
| 872 | if (unlikely(!f.file)) |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 873 | return -EBADF; |
| 874 | |
| 875 | /* verify that this is indeed an fanotify instance */ |
| 876 | ret = -EINVAL; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 877 | if (unlikely(f.file->f_op != &fanotify_fops)) |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 878 | goto fput_and_out; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 879 | group = f.file->private_data; |
Eric Paris | 4231a23 | 2010-10-28 17:21:56 -0400 | [diff] [blame] | 880 | |
| 881 | /* |
| 882 | * group->priority == FS_PRIO_0 == FAN_CLASS_NOTIF. These are not |
| 883 | * allowed to set permissions events. |
| 884 | */ |
| 885 | ret = -EINVAL; |
| 886 | if (mask & FAN_ALL_PERM_EVENTS && |
| 887 | group->priority == FS_PRIO_0) |
| 888 | goto fput_and_out; |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 889 | |
Heinrich Schuchardt | 0a8dd2d | 2014-06-04 16:05:40 -0700 | [diff] [blame] | 890 | if (flags & FAN_MARK_FLUSH) { |
| 891 | ret = 0; |
| 892 | if (flags & FAN_MARK_MOUNT) |
| 893 | fsnotify_clear_vfsmount_marks_by_group(group); |
| 894 | else |
| 895 | fsnotify_clear_inode_marks_by_group(group); |
| 896 | goto fput_and_out; |
| 897 | } |
| 898 | |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 899 | ret = fanotify_find_path(dfd, pathname, &path, flags); |
| 900 | if (ret) |
| 901 | goto fput_and_out; |
| 902 | |
| 903 | /* inode held in place by reference to path; group by fget on fd */ |
Andreas Gruenbacher | eac8e9e | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 904 | if (!(flags & FAN_MARK_MOUNT)) |
Eric Paris | 0ff21db | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 905 | inode = path.dentry->d_inode; |
| 906 | else |
| 907 | mnt = path.mnt; |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 908 | |
| 909 | /* create/update an inode mark */ |
Heinrich Schuchardt | 0a8dd2d | 2014-06-04 16:05:40 -0700 | [diff] [blame] | 910 | switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE)) { |
Andreas Gruenbacher | c6223f4 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 911 | case FAN_MARK_ADD: |
Andreas Gruenbacher | eac8e9e | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 912 | if (flags & FAN_MARK_MOUNT) |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 913 | ret = fanotify_add_vfsmount_mark(group, mnt, mask, flags); |
Eric Paris | 0ff21db | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 914 | else |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 915 | ret = fanotify_add_inode_mark(group, inode, mask, flags); |
Andreas Gruenbacher | c6223f4 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 916 | break; |
| 917 | case FAN_MARK_REMOVE: |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 918 | if (flags & FAN_MARK_MOUNT) |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 919 | ret = fanotify_remove_vfsmount_mark(group, mnt, mask, flags); |
Andreas Gruenbacher | f364019 | 2009-12-17 21:24:29 -0500 | [diff] [blame] | 920 | else |
Eric Paris | b9e4e3b | 2009-12-17 21:24:33 -0500 | [diff] [blame] | 921 | ret = fanotify_remove_inode_mark(group, inode, mask, flags); |
Andreas Gruenbacher | c6223f4 | 2009-12-17 21:24:28 -0500 | [diff] [blame] | 922 | break; |
| 923 | default: |
| 924 | ret = -EINVAL; |
| 925 | } |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 926 | |
| 927 | path_put(&path); |
| 928 | fput_and_out: |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 929 | fdput(f); |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 930 | return ret; |
Eric Paris | bbaa416 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 931 | } |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 932 | |
Al Viro | 91c2e0b | 2013-03-05 20:10:59 -0500 | [diff] [blame] | 933 | #ifdef CONFIG_COMPAT |
| 934 | COMPAT_SYSCALL_DEFINE6(fanotify_mark, |
| 935 | int, fanotify_fd, unsigned int, flags, |
| 936 | __u32, mask0, __u32, mask1, int, dfd, |
| 937 | const char __user *, pathname) |
| 938 | { |
| 939 | return sys_fanotify_mark(fanotify_fd, flags, |
| 940 | #ifdef __BIG_ENDIAN |
Al Viro | 91c2e0b | 2013-03-05 20:10:59 -0500 | [diff] [blame] | 941 | ((__u64)mask0 << 32) | mask1, |
Heiko Carstens | 592f6b8 | 2014-01-27 17:07:19 -0800 | [diff] [blame] | 942 | #else |
| 943 | ((__u64)mask1 << 32) | mask0, |
Al Viro | 91c2e0b | 2013-03-05 20:10:59 -0500 | [diff] [blame] | 944 | #endif |
| 945 | dfd, pathname); |
| 946 | } |
| 947 | #endif |
| 948 | |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 949 | /* |
Justin P. Mattock | ae0e47f | 2011-03-01 15:06:02 +0100 | [diff] [blame] | 950 | * fanotify_user_setup - Our initialization function. Note that we cannot return |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 951 | * error because we have compiled-in VFS hooks. So an (unlikely) failure here |
| 952 | * must result in panic(). |
| 953 | */ |
| 954 | static int __init fanotify_user_setup(void) |
| 955 | { |
| 956 | fanotify_mark_cache = KMEM_CACHE(fsnotify_mark, SLAB_PANIC); |
Jan Kara | 7053aee | 2014-01-21 15:48:14 -0800 | [diff] [blame] | 957 | fanotify_event_cachep = KMEM_CACHE(fanotify_event_info, SLAB_PANIC); |
Jan Kara | f083441 | 2014-04-03 14:46:33 -0700 | [diff] [blame] | 958 | #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS |
| 959 | fanotify_perm_event_cachep = KMEM_CACHE(fanotify_perm_event_info, |
| 960 | SLAB_PANIC); |
| 961 | #endif |
Eric Paris | 2a3edf8 | 2009-12-17 21:24:26 -0500 | [diff] [blame] | 962 | |
| 963 | return 0; |
| 964 | } |
| 965 | device_initcall(fanotify_user_setup); |