anon_inodes: mark the anon inode private
Inotify was switched to use anon_inode instead of its own private filesystem
which only had one inode in commit c44dcc56d2b5c7 "switch inotify_user to
anon_inode"
The problem with this is that now the inotify inode is not a distinct inode
which can be managed by LSMs. userspace tools which use inotify were allowed
to use the inotify inode but may not have had permission to do read/write type
operations on the anon_inode. After looking at the anon_inode and its users
it looks like the best solution is to just mark the anon_inode as S_PRIVATE
so the security system will ignore it.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c
index 9f0bf13..2de0095 100644
--- a/fs/anon_inodes.c
+++ b/fs/anon_inodes.c
@@ -209,6 +209,7 @@
inode->i_mode = S_IRUSR | S_IWUSR;
inode->i_uid = current_fsuid();
inode->i_gid = current_fsgid();
+ inode->i_flags |= S_PRIVATE;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
return inode;
}