LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Paul Moore <paul@paul-moore.com>
To: Richard Guy Briggs <rgb@redhat.com>
Cc: Linux-Audit Mailing List <linux-audit@redhat.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Linux NetDev Upstream Mailing List <netdev@vger.kernel.org>,
	Netfilter Devel List <netfilter-devel@vger.kernel.org>,
	Linux Security Module list
	<linux-security-module@vger.kernel.org>,
	Integrity Measurement Architecture
	<linux-integrity@vger.kernel.org>,
	SElinux list <selinux@tycho.nsa.gov>,
	Eric Paris <eparis@redhat.com>, Steve Grubb <sgrubb@redhat.com>,
	Ingo Molnar <mingo@redhat.com>,
	David Howells <dhowells@redhat.com>
Subject: Re: [PATCH ghak81 RFC V1 3/5] audit: use inline function to get audit context
Date: Wed, 9 May 2018 11:28:58 -0400	[thread overview]
Message-ID: <CAHC9VhSbMaJ72jJnEivDd-M2UXDomexva8B-xsWXapTyeF0JVQ@mail.gmail.com> (raw)
In-Reply-To: <0e43c5135c197209b3189032d538244571e7443d.1525466167.git.rgb@redhat.com>

On Fri, May 4, 2018 at 4:54 PM, Richard Guy Briggs <rgb@redhat.com> wrote:
> Recognizing that the audit context is an internal audit value, use an
> access function to retrieve the audit context pointer for the task
> rather than reaching directly into the task struct to get it.
>
> Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
> ---
>  include/linux/audit.h                | 16 ++++++++---
>  include/net/xfrm.h                   |  2 +-
>  kernel/audit.c                       |  4 +--
>  kernel/audit_watch.c                 |  2 +-
>  kernel/auditsc.c                     | 52 ++++++++++++++++++------------------
>  net/bridge/netfilter/ebtables.c      |  2 +-
>  net/core/dev.c                       |  2 +-
>  net/netfilter/x_tables.c             |  2 +-
>  net/netlabel/netlabel_user.c         |  2 +-
>  security/integrity/ima/ima_api.c     |  2 +-
>  security/integrity/integrity_audit.c |  2 +-
>  security/lsm_audit.c                 |  2 +-
>  security/selinux/hooks.c             |  4 +--
>  security/selinux/selinuxfs.c         |  6 ++---
>  security/selinux/ss/services.c       | 12 ++++-----
>  15 files changed, 60 insertions(+), 52 deletions(-)
>
> diff --git a/include/linux/audit.h b/include/linux/audit.h
> index 5f86f7c..93e4c61 100644
> --- a/include/linux/audit.h
> +++ b/include/linux/audit.h
> @@ -235,26 +235,30 @@ extern void __audit_inode_child(struct inode *parent,
>  extern void __audit_seccomp(unsigned long syscall, long signr, int code);
>  extern void __audit_ptrace(struct task_struct *t);
>
> +static inline struct audit_context *audit_context(struct task_struct *task)
> +{
> +       return task->audit_context;
> +}

Another case where I think I agree with everything here on principle,
especially when one considers it in the larger context of the audit
container ID work.  However, I think we might be able to somply this a
bit by eliminating the parameter to the new audit_context() helper and
making it always reference the current task_struct.  Based on this
patch it would appear that this change would work for all callers
except for audit_take_context() and __audit_syscall_entry(), both of
which are contained within the core audit code and are enough of a
special case that I think it is acceptable for them to access the
context directly.  I'm trying to think of reasons why a non-audit
kernel subsystem would ever need to access the audit context of a
process other than current and I can't think of any ... removing the
task_struct pointer might help prevent mistakes/abuse in the future.

> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 6e3ceb9..a4bbdcc 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -836,7 +836,7 @@ static inline struct audit_context *audit_take_context(struct task_struct *tsk,
>                                                       int return_valid,
>                                                       long return_code)
>  {
> -       struct audit_context *context = tsk->audit_context;
> +       struct audit_context *context = audit_context(tsk);
>
>         if (!context)
>                 return NULL;
> @@ -1510,7 +1510,7 @@ void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
>                            unsigned long a3, unsigned long a4)
>  {
>         struct task_struct *tsk = current;
> -       struct audit_context *context = tsk->audit_context;
> +       struct audit_context *context = audit_context(tsk);
>         enum audit_state     state;
>
>         if (!audit_enabled || !context)

-- 
paul moore
www.paul-moore.com

  reply	other threads:[~2018-05-09 15:29 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-04 20:54 [PATCH ghak81 RFC V1 0/5] audit: group task params Richard Guy Briggs
2018-05-04 20:54 ` [PATCH ghak81 RFC V1 1/5] audit: normalize loginuid read access Richard Guy Briggs
2018-05-09 15:13   ` Paul Moore
2018-05-10 21:21     ` Richard Guy Briggs
2018-05-11 22:17       ` Richard Guy Briggs
2018-05-04 20:54 ` [PATCH ghak81 RFC V1 2/5] audit: convert sessionid unset to a macro Richard Guy Briggs
2018-05-09  1:34   ` Richard Guy Briggs
2018-05-09 15:18     ` Paul Moore
2018-05-04 20:54 ` [PATCH ghak81 RFC V1 3/5] audit: use inline function to get audit context Richard Guy Briggs
2018-05-09 15:28   ` Paul Moore [this message]
2018-05-10 21:17     ` Richard Guy Briggs
2018-05-04 20:54 ` [PATCH ghak81 RFC V1 4/5] audit: use inline function to set " Richard Guy Briggs
2018-05-09  2:07   ` Tobin C. Harding
2018-05-09 12:09     ` Richard Guy Briggs
2018-05-04 20:54 ` [PATCH ghak81 RFC V1 5/5] audit: collect audit task parameters Richard Guy Briggs
2018-05-09 15:46   ` Paul Moore
2018-05-10 21:26     ` Richard Guy Briggs
2018-05-09 15:53 ` [PATCH ghak81 RFC V1 0/5] audit: group task params Paul Moore

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CAHC9VhSbMaJ72jJnEivDd-M2UXDomexva8B-xsWXapTyeF0JVQ@mail.gmail.com \
    --to=paul@paul-moore.com \
    --cc=dhowells@redhat.com \
    --cc=eparis@redhat.com \
    --cc=linux-audit@redhat.com \
    --cc=linux-integrity@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=netdev@vger.kernel.org \
    --cc=netfilter-devel@vger.kernel.org \
    --cc=rgb@redhat.com \
    --cc=selinux@tycho.nsa.gov \
    --cc=sgrubb@redhat.com \
    --subject='Re: [PATCH ghak81 RFC V1 3/5] audit: use inline function to get audit context' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).