[PATCH] audit: add task history record

[Paul Moore]

On Fri, Aug 11, 2023 at 6:58 AM Tetsuo Handa
<penguin-kernel at i-love.sakura.ne.jp> wrote:
>
> When an unexpected system event occurs, the administrator may want to
> identify which application triggered the event. For example, unexpected
> process termination is still a real concern enough to write articles
> like https://access.redhat.com/solutions/165993 .
>
> This patch adds a record which emits TOMOYO-like task history information
> into the audit logs for better understanding of unexpected system events.
>
>   type=UNKNOWN[1340] msg=audit(1691750738.271:108): history="name=swapper/0;pid=1;start=20230811194329=>name=init;pid=1;start=20230811194343=>name=systemd;pid=1;start=20230811194439=>name=sshd;pid=3660;start=20230811104504=>name=sshd;pid=3767;start=20230811104535"

While I respect your persistence, we've talked about this quite a bit
already in other threads.  What you are trying to do is already
possible with audit and/or TOMOYO enabled and configured so I see no
reason why we want to merge this.  I understand your frustration that
TOMOYO is not enabled by your prefered distribution, but adding
additional (and arguably redundant code) code to the upstream kernel
is not a solution I am willing to support and maintain long term.

> To be able to avoid bloating audit log files due to this information, this
> patch uses audit_history= kernel command line parameter that controls max
> length of history in bytes (default is 1024, and setting to 0 disables
> recording and emitting).
>
> Unlike execve()'s argv record, records in this history information is
> emitted as one string in order to reduce bloat of the audit log files.
> This information can be split into an array using => as the tokenizer.
> But don't expect that you can compare array elements throughout the whole
> audit logs by splitting into an array, for old records get removed from
> history when history became too long to append the newest record. This
> history information is meant to be interpreted by humans rather than be
> analyzed by programs.
>
> Signed-off-by: Tetsuo Handa <penguin-kernel at I-love.SAKURA.ne.jp>
> ---
>  fs/exec.c                  |   1 +
>  include/linux/audit.h      |   5 ++
>  include/linux/sched.h      |   1 +
>  include/uapi/linux/audit.h |   1 +
>  init/init_task.c           |   7 +++
>  kernel/audit.c             |   1 +
>  kernel/auditsc.c           | 108 +++++++++++++++++++++++++++++++++++++
>  7 files changed, 124 insertions(+)

-- 
paul-moore.com