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    SubjectRe: [PATCH] split security_key_alloc into two functions
    Quoting Stephen Smalley (sds@tycho.nsa.gov):
    > On Tue, 2006-03-28 at 07:05 -0600, Serge E. Hallyn wrote:
    > > The security_key_alloc() function acted as both an authorizer and
    > > security structure allocation function. These roles should be
    > > separated. There are two reasons for this.
    > >
    > > First, if two modules are stacked, the first module might grant
    > > permission and allocate security data, after which the second
    > > module refuses permission.
    > >
    > > Second, by adding a security_post_alloc() function after the
    > > serial number has been assigned, security modules can append
    > > useful info.
    >
    > Are you sure that the key cannot be accessed (looked up) by another
    > process as soon as it is assigned a serial number? If it can be, then
    > you risk having it accessed before its security structure is set up.

    Ah, that makes sense, and even rings a bell.

    So if we were to add a post_alloc() hook, it should likely go into
    key_alloc_serial() under the key_serial_lock?

    Still assuming that storing the serial number is desirable...

    thanks,
    -serge
    -
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