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

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

[Silvio Gissi]

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);
 		}
 	}
 
-- 
2.34.1

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

[Jarkko Sakkinen]

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

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

[Jarkko Sakkinen]

On Tue Mar 19, 2024 at 1:27 AM EET, Jarkko Sakkinen wrote:
> 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/

I've applied this to my tree. Can drop on request but otherwise
including to rc2 PR.

BR, Jarkko