Re: [PATCH ghak90 V5 06/10] audit: add support for non-syscall auxiliary records

[Richard Guy Briggs <rgb@redhat.com>]

On 2019-04-01 10:49, Paul Moore wrote:
> On Fri, Mar 15, 2019 at 2:34 PM Richard Guy Briggs <rgb@redhat.com> wrote:
> > Standalone audit records have the timestamp and serial number generated
> > on the fly and as such are unique, making them standalone.  This new
> > function audit_alloc_local() generates a local audit context that will
> > be used only for a standalone record and its auxiliary record(s).  The
> > context is discarded immediately after the local associated records are
> > produced.
> >
> > Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
> > Acked-by: Serge Hallyn <serge@hallyn.com>
> > ---
> >  include/linux/audit.h |  8 ++++++++
> >  kernel/audit.h        |  1 +
> >  kernel/auditsc.c      | 35 ++++++++++++++++++++++++++++++-----
> >  3 files changed, 39 insertions(+), 5 deletions(-)
> 
> ...
> 
> > diff --git a/include/linux/audit.h b/include/linux/audit.h
> > index ebd6625ca80e..6db5aba7cc01 100644
> > --- a/include/linux/audit.h
> > +++ b/include/linux/audit.h
> > @@ -285,6 +285,8 @@ static inline void audit_log_contid(struct audit_context *context, u64 contid)
> >
> >  /* These are defined in auditsc.c */
> >                                 /* Public API */
> > +extern struct audit_context *audit_alloc_local(gfp_t gfpflags);
> > +extern void audit_free_context(struct audit_context *context);
> >  extern void __audit_syscall_entry(int major, unsigned long a0, unsigned long a1,
> >                                   unsigned long a2, unsigned long a3);
> >  extern void __audit_syscall_exit(int ret_success, long ret_value);
> > @@ -512,6 +514,12 @@ static inline void audit_fanotify(unsigned int response)
> >  extern int audit_n_rules;
> >  extern int audit_signals;
> >  #else /* CONFIG_AUDITSYSCALL */
> > +static inline struct audit_context *audit_alloc_local(gfp_t gfpflags)
> > +{
> > +       return NULL;
> > +}
> > +static inline void audit_free_context(struct audit_context *context)
> > +{ }
> >  static inline void audit_syscall_entry(int major, unsigned long a0,
> >                                        unsigned long a1, unsigned long a2,
> >                                        unsigned long a3)
> > diff --git a/kernel/audit.h b/kernel/audit.h
> > index c5ac6436317e..2a1a8b8a8019 100644
> > --- a/kernel/audit.h
> > +++ b/kernel/audit.h
> > @@ -111,6 +111,7 @@ struct audit_proctitle {
> >  struct audit_context {
> >         int                 dummy;      /* must be the first element */
> >         int                 in_syscall; /* 1 if task is in a syscall */
> > +       bool                local;      /* local context needed */
> 
> It's very possible I've missed it, but "local" never gets used in any
> meaningful way in this patchset does it?

It is used in audit_alloc_local() to signal to audit_get_stamp() that in
absence of a syscall flag, check for a local flag to continue rather
than return.

> >         enum audit_state    state, current_state;
> >         unsigned int        serial;     /* serial number for record */
> >         int                 major;      /* syscall number */
> 
> paul moore

- RGB

--
Richard Guy Briggs <rgb@redhat.com>
Sr. S/W Engineer, Kernel Security, Base Operating Systems
Remote, Ottawa, Red Hat Canada
IRC: rgb, SunRaycer
Voice: +1.647.777.2635, Internal: (81) 32635