diff options
Diffstat (limited to '')
| -rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 22fb1cf7e1fc..f69c451018e3 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -1591,11 +1591,10 @@ static int fanotify_test_fid(struct dentry *dentry) * We need to make sure that the file system supports at least * encoding a file handle so user can use name_to_handle_at() to * compare fid returned with event to the file handle of watched - * objects. However, name_to_handle_at() requires that the - * filesystem also supports decoding file handles. + * objects. However, even the relaxed AT_HANDLE_FID flag requires + * at least empty export_operations for ecoding unique file ids. */ - if (!dentry->d_sb->s_export_op || - !dentry->d_sb->s_export_op->fh_to_dentry) + if (!dentry->d_sb->s_export_op) return -EOPNOTSUPP; return 0; @@ -1624,6 +1623,20 @@ static int fanotify_events_supported(struct fsnotify_group *group, return -EINVAL; /* + * mount and sb marks are not allowed on kernel internal pseudo fs, + * like pipe_mnt, because that would subscribe to events on all the + * anonynous pipes in the system. + * + * SB_NOUSER covers all of the internal pseudo fs whose objects are not + * exposed to user's mount namespace, but there are other SB_KERNMOUNT + * fs, like nsfs, debugfs, for which the value of allowing sb and mount + * mark is questionable. For now we leave them alone. + */ + if (mark_type != FAN_MARK_INODE && + path->mnt->mnt_sb->s_flags & SB_NOUSER) + return -EINVAL; + + /* * We shouldn't have allowed setting dirent events and the directory * flags FAN_ONDIR and FAN_EVENT_ON_CHILD in mask of non-dir inode, * but because we always allowed it, error only when using new APIs. |