Re: [PATCH] selinux: return -ENOMEM if kzalloc() fails

[Paul Moore]

On Fri, Jun 30, 2017 at 9:10 AM, Tetsuo Handa
 wrote:
> Stephen Smalley wrote:
>> On Fri, 2017-06-30 at 10:56 +0300, Dan Carpenter wrote:
>> > We accidentally return success instead of -ENOMEM on this failure
>> > path.
>> >
>> > Fixes: 409dcf31538a ("selinux: Add a cache for quicker retreival of
>> > PKey SIDs")
>> > Signed-off-by: Dan Carpenter 
>>
>> NAK, that's intentional.  See the comment just above the code in
>> question.
>
> If allocation failure is no problem, please consider using
> GFP_NOWAIT | __GFP_NOMEMALLOC | __GFP_NOWARN instead of
> GFP_ATOMIC, for memory reserves is mainly targeted for OOM victims.

I have a todo item to try and consolidate some of the SELinux object
cache code, this seems like something worth experimenting with when
that happens.

-- 
paul moore
www.paul-moore.com

Re: [PATCH] selinux: return -ENOMEM if kzalloc() fails

[Tetsuo Handa]

Stephen Smalley wrote:
> On Fri, 2017-06-30 at 10:56 +0300, Dan Carpenter wrote:
> > We accidentally return success instead of -ENOMEM on this failure
> > path.
> > 
> > Fixes: 409dcf31538a ("selinux: Add a cache for quicker retreival of
> > PKey SIDs")
> > Signed-off-by: Dan Carpenter 
> 
> NAK, that's intentional.  See the comment just above the code in
> question.

If allocation failure is no problem, please consider using
GFP_NOWAIT | __GFP_NOMEMALLOC | __GFP_NOWARN instead of
GFP_ATOMIC, for memory reserves is mainly targeted for OOM victims.

Re: [PATCH] selinux: return -ENOMEM if kzalloc() fails

[Stephen Smalley]

On Fri, 2017-06-30 at 10:56 +0300, Dan Carpenter wrote:
> We accidentally return success instead of -ENOMEM on this failure
> path.
> 
> Fixes: 409dcf31538a ("selinux: Add a cache for quicker retreival of
> PKey SIDs")
> Signed-off-by: Dan Carpenter 

NAK, that's intentional.  See the comment just above the code in
question.

> 
> diff --git a/security/selinux/ibpkey.c b/security/selinux/ibpkey.c
> index e3614ee5f1c0..36e61f622b5a 100644
> --- a/security/selinux/ibpkey.c
> +++ b/security/selinux/ibpkey.c
> @@ -160,8 +160,10 @@ static int sel_ib_pkey_sid_slow(u64
> subnet_prefix, u16 pkey_num, u32 *sid)
>    * is valid, it just won't be added to the cache.
>    */
>   new = kzalloc(sizeof(*new), GFP_ATOMIC);
> - if (!new)
> + if (!new) {
> + ret = -ENOMEM;
>   goto out;
> + }
>  
>   new->psec.subnet_prefix = subnet_prefix;
>   new->psec.pkey = pkey_num;

[PATCH] selinux: return -ENOMEM if kzalloc() fails

[Dan Carpenter]

We accidentally return success instead of -ENOMEM on this failure path.

Fixes: 409dcf31538a ("selinux: Add a cache for quicker retreival of PKey SIDs")
Signed-off-by: Dan Carpenter 

diff --git a/security/selinux/ibpkey.c b/security/selinux/ibpkey.c
index e3614ee5f1c0..36e61f622b5a 100644
--- a/security/selinux/ibpkey.c
+++ b/security/selinux/ibpkey.c
@@ -160,8 +160,10 @@ static int sel_ib_pkey_sid_slow(u64 subnet_prefix, u16 
pkey_num, u32 *sid)
 * is valid, it just won't be added to the cache.
 */
new = kzalloc(sizeof(*new), GFP_ATOMIC);
-   if (!new)
+   if (!new) {
+   ret = -ENOMEM;
goto out;
+   }
 
new->psec.subnet_prefix = subnet_prefix;
new->psec.pkey = pkey_num;