Re: [PATCH 1/1] audit,io_uring,io-wq: call __audit_uring_exit for dummy contexts

From: Paul Moore
Date: Tue May 17 2022 - 09:13:22 EST


On Tue, May 17, 2022 at 6:33 AM Julian Orth <ju.orth@xxxxxxxxx> wrote:
>
> Not calling the function for dummy contexts will cause the context to
> not be reset. During the next syscall, this will cause an error in
> __audit_syscall_entry:
>
> WARN_ON(context->context != AUDIT_CTX_UNUSED);
> WARN_ON(context->name_count);
> if (context->context != AUDIT_CTX_UNUSED || context->name_count) {
> audit_panic("unrecoverable error in audit_syscall_entry()");
> return;
> }
>
> These problematic dummy contexts are created via the following call
> chain:
>
> exit_to_user_mode_prepare
> -> arch_do_signal_or_restart
> -> get_signal
> -> task_work_run
> -> tctx_task_work
> -> io_req_task_submit
> -> io_issue_sqe
> -> audit_uring_entry
>
> Fixes: 5bd2182d58e9 ("audit,io_uring,io-wq: add some basic audit support to io_uring")
> Signed-off-by: Julian Orth <ju.orth@xxxxxxxxx>
> ---
> include/linux/audit.h | 2 +-
> kernel/auditsc.c | 6 ++++++
> 2 files changed, 7 insertions(+), 1 deletion(-)

Hi Julian,

Thanks for the report and the patch too! I agree that it does seem a
little odd that we haven't seen this before, let me dig into this a
bit more today and respond back.

--
paul-moore.com