From: Martin KaFai Lau <kafai@fb.com>
To: KP Singh <kpsingh@chromium.org>
Cc: <linux-kernel@vger.kernel.org>, <bpf@vger.kernel.org>,
<linux-security-module@vger.kernel.org>,
Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Paul Turner <pjt@google.com>, Jann Horn <jannh@google.com>,
Florent Revest <revest@chromium.org>
Subject: Re: [PATCH bpf-next v4 2/4] bpf: Implement bpf_local_storage for inodes
Date: Wed, 15 Jul 2020 14:57:51 -0700 [thread overview]
Message-ID: <20200715215751.6llgungzff66iwxh@kafai-mbp> (raw)
In-Reply-To: <20200709101239.3829793-3-kpsingh@chromium.org>
On Thu, Jul 09, 2020 at 12:12:37PM +0200, KP Singh wrote:
> From: KP Singh <kpsingh@google.com>
>
> Similar to bpf_local_storage for sockets, add local storage for inodes.
> The life-cycle of storage is managed with the life-cycle of the inode.
> i.e. the storage is destroyed along with the owning inode.
>
> The BPF LSM allocates an __rcu pointer to the bpf_local_storage in the
> security blob which are now stackable and can co-exist with other LSMs.
>
> Signed-off-by: KP Singh <kpsingh@google.com>
[ ... ]
> +static void *bpf_inode_storage_lookup_elem(struct bpf_map *map, void *key)
> +{
> + struct bpf_local_storage_data *sdata;
> + struct inode *inode;
> + int err = -EINVAL;
> +
> + if (key) {
> + inode = *(struct inode **)(key);
The bpf_inode_storage_lookup_elem() here and the (update|delete)_elem() below
are called from the userspace syscall. How the userspace may provide this key?
> + sdata = inode_storage_lookup(inode, map, true);
> + return sdata ? sdata->data : NULL;
> + }
> +
> + return ERR_PTR(err);
> +}
> +
> +static int bpf_inode_storage_update_elem(struct bpf_map *map, void *key,
> + void *value, u64 map_flags)
> +{
> + struct bpf_local_storage_data *sdata;
> + struct inode *inode;
> + int err = -EINVAL;
> +
> + if (key) {
> + inode = *(struct inode **)(key);
> + sdata = map->ops->map_local_storage_update(inode, map, value,
> + map_flags);
> + return PTR_ERR_OR_ZERO(sdata);
> + }
> + return err;
> +}
> +
> +static int inode_storage_delete(struct inode *inode, struct bpf_map *map)
> +{
> + struct bpf_local_storage_data *sdata;
> +
> + sdata = inode_storage_lookup(inode, map, false);
> + if (!sdata)
> + return -ENOENT;
> +
> + bpf_selem_unlink_map_elem(SELEM(sdata));
> +
> + return 0;
> +}
> +
> +static int bpf_inode_storage_delete_elem(struct bpf_map *map, void *key)
> +{
> + struct inode *inode;
> + int err = -EINVAL;
> +
> + if (key) {
> + inode = *(struct inode **)(key);
> + err = inode_storage_delete(inode, map);
> + }
> +
> + return err;
> +}
> +
[ ... ]
> +static int inode_storage_map_btf_id;
> +const struct bpf_map_ops inode_storage_map_ops = {
> + .map_alloc_check = bpf_local_storage_map_alloc_check,
> + .map_alloc = inode_storage_map_alloc,
> + .map_free = inode_storage_map_free,
> + .map_get_next_key = notsupp_get_next_key,
> + .map_lookup_elem = bpf_inode_storage_lookup_elem,
> + .map_update_elem = bpf_inode_storage_update_elem,
> + .map_delete_elem = bpf_inode_storage_delete_elem,
> + .map_check_btf = bpf_local_storage_map_check_btf,
> + .map_btf_name = "bpf_local_storage_map",
> + .map_btf_id = &inode_storage_map_btf_id,
> + .map_local_storage_alloc = inode_storage_alloc,
> + .map_selem_alloc = inode_selem_alloc,
> + .map_local_storage_update = inode_storage_update,
> + .map_local_storage_unlink = unlink_inode_storage,
> +};
> +
next prev parent reply other threads:[~2020-07-15 21:58 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-09 10:12 [PATCH bpf-next v4 0/4] Generalizing bpf_local_storage KP Singh
2020-07-09 10:12 ` [PATCH bpf-next v4 1/4] bpf: Generalize bpf_sk_storage KP Singh
2020-07-10 6:59 ` Martin KaFai Lau
[not found] ` <CACYkzJ7szyY8vY=Rv_gr7RbMty=pxyZpPPzTpaREAa5_k0tAfg@mail.gmail.com>
[not found] ` <20200715064339.gxtb4qwl77macuxt@kafai-mbp>
[not found] ` <CACYkzJ7GmSPt8WV5nSNB2irH+Dn9QywSabZyLvqEcae2-jTuHQ@mail.gmail.com>
2020-07-15 8:57 ` KP Singh
2020-07-20 11:18 ` kernel test robot
2020-07-09 10:12 ` [PATCH bpf-next v4 2/4] bpf: Implement bpf_local_storage for inodes KP Singh
2020-07-15 21:57 ` Martin KaFai Lau [this message]
2020-07-15 22:59 ` KP Singh
2020-07-20 22:44 ` KP Singh
2020-07-09 10:12 ` [PATCH bpf-next v4 3/4] bpf: Allow local storage to be used from LSM programs KP Singh
2020-07-09 10:12 ` [PATCH bpf-next v4 4/4] bpf: Add selftests for local_storage KP Singh
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=20200715215751.6llgungzff66iwxh@kafai-mbp \
--to=kafai@fb.com \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=jannh@google.com \
--cc=kpsingh@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=pjt@google.com \
--cc=revest@chromium.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 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).