Re: [PATCH] keys: Fix overwrite of key expiration on instantiation

["Jarkko Sakkinen" <jarkko@kernel.org>]

On Fri Mar 15, 2024 at 9:05 PM EET, Silvio Gissi wrote:
> The expiry time of a key is unconditionally overwritten during
> instantiation, defaulting to turn it permanent. This causes a problem
> for DNS resolution as the expiration set by user-space is overwritten to
> TIME64_MAX, disabling further DNS updates. Fix this by restoring the
> condition that key_set_expiry is only called when the pre-parser sets a
> specific expiry.
>
> Fixes: 39299bdd2546 ("keys, dns: Allow key types (eg. DNS) to be reclaimed immediately on expiry")
> Signed-off-by: Silvio Gissi <sifonsec@amazon.com>
> cc: David Howells <dhowells@redhat.com>
> cc: Hazem Mohamed Abuelfotoh <abuehaze@amazon.com>
> cc: linux-afs@lists.infradead.org
> cc: linux-cifs@vger.kernel.org
> cc: keyrings@vger.kernel.org
> cc: netdev@vger.kernel.org
> cc: stable@vger.kernel.org
> ---
>  security/keys/key.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/security/keys/key.c b/security/keys/key.c
> index 560790038329..0aa5f01d16ff 100644
> --- a/security/keys/key.c
> +++ b/security/keys/key.c
> @@ -463,7 +463,8 @@ static int __key_instantiate_and_link(struct key *key,
>  			if (authkey)
>  				key_invalidate(authkey);
>  
> -			key_set_expiry(key, prep->expiry);
> +			if (prep->expiry != TIME64_MAX)
> +				key_set_expiry(key, prep->expiry);
>  		}
>  	}
>  

I checked the original commit and reflected to the fix:

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

David, I can pick this one too as I'm anyway sending PR for rc2?

[1] https://lore.kernel.org/keyrings/CZX77XLG67HZ.UAU4NUQO27JP@kernel.org/

BR, Jarkko