On Wed, May 17, 2017 at 9:04 AM, William Roberts
[off-list ref] wrote:

On Wed, May 17, 2017 at 8:43 AM, Sebastien Buisson
[off-list ref] wrote:

quoted

2017-05-17 17:34 GMT+02:00 William Roberts [off-list ref]:

quoted

quoted

quoted

quoted

quoted

Is there a particular reason to not just return policybrief_len here as
well, for consistency in the interface?  How do you intend to use this
value in the caller?

As called in the other patch to expose policy brief via selinuxfs
(sel_read_policybrief), the intent is to provide the caller with the
length of the string returned.
Or should I set *len to policy brief_len here, and just make the
caller aware that the returned length is in fact the length of the
buffer (i.e. including terminating NUL byte)?

What is the caller supposed to do with length? This interface seemed kind of
odd. If it's guaranteed NUL byte terminated, do they even need length?

The length is useful as an input parameter in case the caller provides
its own buffer (instead of letting the function allocate one), and as

This is what I don't get, why doesn't the function just always allocate?

For performance reasons mainly. The caller would have a statically
allocated buffer, reused every time it needs to get the policy brief
info.

I'm assuming in the Lustre code you're going to call security_policy_brief(),
how would the caller know how big that buffer is going to be?

I'm looking at both v5 patches, I don't see where it's being called with alloc
set to false.

I don't see how this works with LSM stacking, I would imagine the security
hook needs to call this routine for each LSM and join them together in
some module name spaced way, which was mentioned before, but I don't
see that either, am I missing it?

Disregard this last statement, I thought more of stacking was in.
--
To unsubscribe from this list: send the line "unsubscribe linux-security-module" in
the body of a message to majordomo at vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html