diff options
Diffstat (limited to 'fs/notify/fanotify/fanotify_user.c')
| -rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 8508ab575017..ec4eadf459ae 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -928,8 +928,11 @@ static int fanotify_test_fid(struct path *path, __kernel_fsid_t *fsid) return 0; } -static int fanotify_events_supported(struct path *path, __u64 mask) +static int fanotify_events_supported(struct path *path, __u64 mask, + unsigned int flags) { + unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS; + /* * Some filesystems such as 'proc' acquire unusual locks when opening * files. For them fanotify permission events have high chances of @@ -941,6 +944,21 @@ static int fanotify_events_supported(struct path *path, __u64 mask) if (mask & FANOTIFY_PERM_EVENTS && path->mnt->mnt_sb->s_type->fs_flags & FS_DISALLOW_NOTIFY_PERM) 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; + return 0; } @@ -1050,7 +1068,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, goto fput_and_out; if (flags & FAN_MARK_ADD) { - ret = fanotify_events_supported(&path, mask); + ret = fanotify_events_supported(&path, mask, flags); if (ret) goto path_put_and_out; } |