From: Kees Cook <keescook@chromium.org>
To: KP Singh <kpsingh@kernel.org>
Cc: linux-security-module@vger.kernel.org, bpf@vger.kernel.org,
paul@paul-moore.com, casey@schaufler-ca.com, song@kernel.org,
daniel@iogearbox.net, ast@kernel.org
Subject: Re: [PATCH v3 4/5] bpf: Only enable BPF LSM hooks when an LSM program is attached
Date: Wed, 20 Sep 2023 09:00:09 -0700 [thread overview]
Message-ID: <202309200859.D8E31893F4@keescook> (raw)
In-Reply-To: <20230918212459.1937798-5-kpsingh@kernel.org>
On Mon, Sep 18, 2023 at 11:24:58PM +0200, KP Singh wrote:
> [...]
> +void bpf_lsm_toggle_hook(void *addr, bool value)
> +{
> + struct lsm_static_call *scalls;
> + struct security_hook_list *h;
> + int i, j;
> +
> + for (i = 0; i < ARRAY_SIZE(bpf_lsm_hooks); i++) {
> + h = &bpf_lsm_hooks[i];
> + scalls = h->scalls;
> + if (h->hook.lsm_callback == addr)
> + continue;
> +
> + for (j = 0; j < MAX_LSM_COUNT; j++) {
> + if (scalls[j].hl != h)
> + continue;
> + if (value)
> + static_branch_enable(scalls[j].active);
> + else
> + static_branch_disable(scalls[j].active);
> + }
> + }
> +}
And this happily works with everything being read-only? I double-checked
these structures, and it seems like the answer is "yes". :)
So, to that end:
Reviewed-by: Kees Cook <keescook@chromium.org>
--
Kees Cook
next prev parent reply other threads:[~2023-09-20 16:00 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-18 21:24 [PATCH v3 0/5] Reduce overhead of LSMs with static calls KP Singh
2023-09-18 21:24 ` [PATCH v3 1/5] kernel: Add helper macros for loop unrolling KP Singh
2023-09-20 15:46 ` Kees Cook
2023-09-20 18:06 ` Casey Schaufler
2023-09-21 21:00 ` Song Liu
2023-09-18 21:24 ` [PATCH v3 2/5] security: Count the LSMs enabled at compile time KP Singh
2023-09-20 15:48 ` Kees Cook
2023-09-20 18:07 ` Casey Schaufler
2023-09-20 19:24 ` Kees Cook
2023-09-21 8:41 ` KP Singh
2023-09-21 20:59 ` Song Liu
2023-09-21 13:20 ` Tetsuo Handa
2023-09-21 13:58 ` KP Singh
2023-09-22 11:25 ` Tetsuo Handa
2023-09-22 14:45 ` KP Singh
2023-09-23 6:56 ` Tetsuo Handa
2023-09-23 16:06 ` KP Singh
2023-09-25 11:03 ` Tetsuo Handa
2023-09-25 11:22 ` KP Singh
2023-10-01 10:51 ` Tetsuo Handa
2023-10-01 14:26 ` KP Singh
2023-10-01 15:00 ` Casey Schaufler
2023-10-02 10:56 ` Tetsuo Handa
2023-10-02 13:04 ` KP Singh
2023-10-02 14:34 ` Tetsuo Handa
2023-09-25 15:48 ` Casey Schaufler
2023-09-23 18:10 ` Casey Schaufler
2023-09-22 14:57 ` Paul Moore
2023-09-23 16:08 ` KP Singh
2023-09-21 14:13 ` KP Singh
2023-09-18 21:24 ` [PATCH v3 3/5] security: Replace indirect LSM hook calls with static calls KP Singh
2023-09-20 15:54 ` Kees Cook
2023-09-21 9:13 ` KP Singh
2023-09-20 18:10 ` Casey Schaufler
2023-09-21 9:14 ` KP Singh
2023-09-21 21:02 ` Song Liu
2023-09-18 21:24 ` [PATCH v3 4/5] bpf: Only enable BPF LSM hooks when an LSM program is attached KP Singh
2023-09-20 16:00 ` Kees Cook [this message]
2023-09-20 18:11 ` Casey Schaufler
2023-09-21 21:04 ` Song Liu
2023-09-18 21:24 ` [PATCH v3 5/5] security: Add CONFIG_SECURITY_HOOK_LIKELY KP Singh
2023-09-20 15:44 ` Kees Cook
2023-09-21 8:53 ` KP Singh
2023-09-21 23:03 ` Song Liu
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=202309200859.D8E31893F4@keescook \
--to=keescook@chromium.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=casey@schaufler-ca.com \
--cc=daniel@iogearbox.net \
--cc=kpsingh@kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=paul@paul-moore.com \
--cc=song@kernel.org \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.