Re: [PATCH] fscrypt: fix keyring memory leak on mount failure

[Eric Biggers]

On Tue, Oct 11, 2022 at 02:38:38PM -0700, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@xxxxxxxxxx>
> 
> Commit d7e7b9af104c ("fscrypt: stop using keyrings subsystem for
> fscrypt_master_key") moved the keyring destruction from __put_super() to
> generic_shutdown_super() so that the filesystem's block device(s) are
> still available.  Unfortunately, this causes a memory leak in the case
> where a mount is attempted with the test_dummy_encryption mount option,
> but the mount fails after the option has already been processed.
> 
> To fix this, attempt the keyring destruction in both places.
> 
> Reported-by: syzbot+104c2a89561289cec13e@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: d7e7b9af104c ("fscrypt: stop using keyrings subsystem for fscrypt_master_key")
> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>

Applied to fscrypt.git#for-stable for 6.1.

As usual, I'd greatly appreciate reviews though...

- Eric