On Mon, Mar 13, 2023 at 03:12:29PM -0700, Eric Biggers wrote:
From: Eric Biggers ebiggers@google.com
fscrypt_destroy_keyring() must be called after all potentially-encrypted inodes were evicted; otherwise it cannot safely destroy the keyring. Since inodes that are in-use by the Landlock LSM don't get evicted until security_sb_delete(), this means that fscrypt_destroy_keyring() must be called *after* security_sb_delete().
This fixes a WARN_ON followed by a NULL dereference, only possible if Landlock was being used on encrypted files.
Fixes: d7e7b9af104c ("fscrypt: stop using keyrings subsystem for fscrypt_master_key") Cc: stable@vger.kernel.org Reported-by: syzbot+93e495f6a4f748827c88@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/00000000000044651705f6ca1e30@google.com Signed-off-by: Eric Biggers ebiggers@google.com
Looks good, Reviewed-by: Christian Brauner brauner@kernel.org