Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Roman Gushchin <guro@fb.com>
To:     <netdev@vger.kernel.org>
CC:     <linux-kernel@vger.kernel.org>, <kernel-team@fb.com>,
        Roman Gushchin <guro@fb.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>
Subject: [PATCH v7 bpf-next 07/14] bpf: don't allow create maps of cgroup local storages
Date:   Thu, 2 Aug 2018 14:27:23 -0700
Message-ID: <20180802212730.18579-8-guro@fb.com>
In-Reply-To: <20180802212730.18579-1-guro@fb.com>
References: <20180802212730.18579-1-guro@fb.com>
MIME-Version: 1.0
Content-Type: text/plain
Received-SPF: None (protection.outlook.com: fb.com does not designate
 permitted sender hosts)
SpamDiagnosticOutput: 1:99
SpamDiagnosticMetadata: NSPM
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Aug 2018 21:28:00.2392 (UTC)
X-MS-Exchange-CrossTenant-Network-Message-Id: a85a6187-2645-4c2b-0715-08d5f8bed2f1
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2
X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY2PR15MB0167
X-OriginatorOrg: fb.com
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-08-02_05:,,
 signatures=0
X-Proofpoint-Spam-Reason: safe
X-FB-Internal: Safe
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

As there is one-to-one relation between a bpf program
and cgroup local storage map, there is no sense in
creating a map of cgroup local storage maps.

Forbid it explicitly to avoid possible side effects.

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
---
 kernel/bpf/map_in_map.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/bpf/map_in_map.c b/kernel/bpf/map_in_map.c
index 1da574612bea..3bfbf4464416 100644
--- a/kernel/bpf/map_in_map.c
+++ b/kernel/bpf/map_in_map.c
@@ -23,7 +23,8 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd)
 	 * is a runtime binding.  Doing static check alone
 	 * in the verifier is not enough.
 	 */
-	if (inner_map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
+	if (inner_map->map_type == BPF_MAP_TYPE_PROG_ARRAY ||
+	    inner_map->map_type == BPF_MAP_TYPE_CGROUP_STORAGE) {
 		fdput(f);
 		return ERR_PTR(-ENOTSUPP);
 	}
-- 
2.14.4