Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20220517103253.22601-1-ju.orth@gmail.com> <20220517103253.22601-2-ju.orth@gmail.com>
In-Reply-To: <20220517103253.22601-2-ju.orth@gmail.com>
From:   Paul Moore <paul@paul-moore.com>
Date:   Tue, 17 May 2022 09:12:34 -0400
Message-ID: <CAHC9VhR_N+N1=3vbbmym36aDA+sUY2c4yRJq74K+=Fr27TBLQw@mail.gmail.com>
Subject: Re: [PATCH 1/1] audit,io_uring,io-wq: call __audit_uring_exit for
 dummy contexts
To:     Julian Orth <ju.orth@gmail.com>
Cc:     Eric Paris <eparis@redhat.com>, linux-audit@redhat.com,
        linux-kernel@vger.kernel.org, Jens Axboe <axboe@kernel.dk>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Tue, May 17, 2022 at 6:33 AM Julian Orth <ju.orth@gmail.com> 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@gmail.com>
> ---
>  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