[PATCH ghak111 V1] audit: deliver siginfo regarless of syscall

[Paul Moore]

On Mon, Apr 8, 2019 at 11:53 PM Richard Guy Briggs <rgb at redhat.com> wrote:
>
> When a process signals the audit daemon (shutdown, rotate, resume,
> reconfig) but syscall auditing is not enabled, we still want to know the
> identity of the process sending the signal to the audit daemon.
>
> Move audit_signal_info() out of syscall auditing to general auditing but
> create a new function audit_signal_info_syscall() to take care of the
> syscall dependent parts for when syscall auditing is enabled.
>
> Please see the github kernel audit issue
> https://github.com/linux-audit/audit-kernel/issues/111
>
> Signed-off-by: Richard Guy Briggs <rgb at redhat.com>
> ---
>  include/linux/audit.h |  6 ++++++
>  kernel/audit.c        | 27 +++++++++++++++++++++++++++
>  kernel/audit.h        |  4 ++--
>  kernel/auditsc.c      | 19 +++----------------
>  kernel/signal.c       |  2 +-
>  5 files changed, 39 insertions(+), 19 deletions(-)

...

> diff --git a/include/linux/audit.h b/include/linux/audit.h
> index 1e69d9fe16da..4a22fc3f824f 100644
> --- a/include/linux/audit.h
> +++ b/include/linux/audit.h
> @@ -226,6 +229,9 @@ static inline unsigned int audit_get_sessionid(struct task_struct *tsk)
>  }
>
>  #define audit_enabled AUDIT_OFF
> +
> +#define audit_signal_info(s, t) AUDIT_OFF
> +

Should this be AUDIT_DISABLED to preserve the current value/behavior?
Technically they should both have a value of zero right now, but since
the AUDIT_DISABLED value isn't explicit it seems safer to go with
AUDIT_DISABLED.

> diff --git a/kernel/audit.h b/kernel/audit.h
> index 958d5b8fc1b3..18a8ae812e9f 100644
> --- a/kernel/audit.h
> +++ b/kernel/audit.h
> @@ -299,7 +299,7 @@ extern bool audit_tree_match(struct audit_chunk *chunk,
>  extern void audit_put_tree(struct audit_tree *tree);
>  extern void audit_kill_trees(struct audit_context *context);
>
> -extern int audit_signal_info(int sig, struct task_struct *t);
> +extern int audit_signal_info_syscall(struct task_struct *t);
>  extern void audit_filter_inodes(struct task_struct *tsk,
>                                 struct audit_context *ctx);
>  extern struct list_head *audit_killed_trees(void);
> @@ -330,7 +330,7 @@ extern void audit_filter_inodes(struct task_struct *tsk,
>  #define audit_tree_path(rule) ""       /* never called */
>  #define audit_kill_trees(context) BUG()
>
> -#define audit_signal_info(s, t) AUDIT_DISABLED
> +#define audit_signal_info_syscall(t) AUDIT_OFF

Similar as above.

-- 
paul moore
www.paul-moore.com