From patchwork Tue Sep 20 15:42:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Pu Lehui X-Patchwork-Id: 12981524 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7329DECAAD8 for ; Tue, 20 Sep 2022 07:43:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231236AbiITHnB (ORCPT ); Tue, 20 Sep 2022 03:43:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46890 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230129AbiITHmm (ORCPT ); Tue, 20 Sep 2022 03:42:42 -0400 Received: from dggsgout11.his.huawei.com (unknown [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2FA5642DC; Tue, 20 Sep 2022 00:41:12 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4MWthK4KHgzKQ0p; Tue, 20 Sep 2022 15:38:41 +0800 (CST) Received: from localhost.localdomain (unknown [10.67.175.61]) by APP2 (Coremail) with SMTP id Syh0CgBH4mt1biljrIh4BA--.36206S2; Tue, 20 Sep 2022 15:40:38 +0800 (CST) From: Pu Lehui To: bpf@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Quentin Monnet , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Pu Lehui , Pu Lehui Subject: [PATCH bpf v4 0/2] Fix wrong cgroup attach flags being assigned to effective progs Date: Tue, 20 Sep 2022 15:42:31 +0000 Message-Id: <20220920154233.1494352-1-pulehui@huaweicloud.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-CM-TRANSID: Syh0CgBH4mt1biljrIh4BA--.36206S2 X-Coremail-Antispam: 1UD129KBjvJXoW7WFWkWF1xKw1DGFy3JFW5Wrg_yoW8KFy3pF WkA3W5Jwn8Wr93J3ySya4jga4rKr48Aw1jy3ZrZr48uFyxtryqyry2k3yFyr17XFsrGw4x Zr15AFy5G3y5taDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9S14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2jI8I6cxK62vIxIIY0VWUZVW8XwA2ocxC64kIII 0Yj41l84x0c7CEw4AK67xGY2AK021l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xv wVC0I7IYx2IY6xkF7I0E14v26r4UJVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4 x0Y4vEx4A2jsIEc7CjxVAFwI0_GcCE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG 64xvF2IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r 1j6r4UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAq YI8I648v4I1lFIxGxcIEc7CjxVA2Y2ka0xkIwI1l42xK82IYc2Ij64vIr41l4I8I3I0E4I kC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWU WwC2zVAF1VAY17CE14v26r4a6rW5MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr 0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWr Zr1j6s0DMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr 1UYxBIdaVFxhVjvjDU0xZFpf9x0pRQo7tUUUUU= X-CM-SenderInfo: psxovxtxl6x35dzhxuhorxvhhfrp/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net From: Pu Lehui When root-cgroup attach multi progs and sub-cgroup attach a override prog, bpftool will display incorrectly for the attach flags of the sub-cgroup’s effective progs: $ bpftool cgroup tree /sys/fs/cgroup effective CgroupPath ID AttachType AttachFlags Name /sys/fs/cgroup 6 cgroup_sysctl multi sysctl_tcp_mem 13 cgroup_sysctl multi sysctl_tcp_mem /sys/fs/cgroup/cg1 20 cgroup_sysctl override sysctl_tcp_mem 6 cgroup_sysctl override sysctl_tcp_mem <- wrong 13 cgroup_sysctl override sysctl_tcp_mem <- wrong /sys/fs/cgroup/cg1/cg2 20 cgroup_sysctl sysctl_tcp_mem 6 cgroup_sysctl sysctl_tcp_mem 13 cgroup_sysctl sysctl_tcp_mem For cg1, obviously, the attach flags of prog6 and prog13 can not be OVERRIDE. And for query with EFFECTIVE flags, exporting attach flags does not make sense. So let's remove the AttachFlags field and the associated logic. After these patches, the above effective cgroup tree will show as bellow: # bpftool cgroup tree /sys/fs/cgroup effective CgroupPath ID AttachType Name /sys/fs/cgroup 6 cgroup_sysctl sysctl_tcp_mem 13 cgroup_sysctl sysctl_tcp_mem /sys/fs/cgroup/cg1 20 cgroup_sysctl sysctl_tcp_mem 6 cgroup_sysctl sysctl_tcp_mem 13 cgroup_sysctl sysctl_tcp_mem /sys/fs/cgroup/cg1/cg2 20 cgroup_sysctl sysctl_tcp_mem 6 cgroup_sysctl sysctl_tcp_mem 13 cgroup_sysctl sysctl_tcp_mem v4: - Reject prog_attach_flags array when effective query. (Martin) - Target to bpf tree. (Martin) v3: https://lore.kernel.org/bpf/20220914161742.3180731-1-pulehui@huaweicloud.com - Don't show attach flags when effective query. (John, sdf, Martin) v2: https://lore.kernel.org/bpf/20220908145304.3436139-1-pulehui@huaweicloud.com - Limit prog_cnt to avoid overflow. (John) - Add more detail message. v1: https://lore.kernel.org/bpf/20220820120234.2121044-1-pulehui@huawei.com Pu Lehui (2): bpf, cgroup: Reject prog_attach_flags array when effective query bpftool: Fix wrong cgroup attach flags being assigned to effective progs include/uapi/linux/bpf.h | 7 +++-- kernel/bpf/cgroup.c | 28 +++++++++++------- tools/bpf/bpftool/cgroup.c | 54 ++++++++++++++++++++++++++++++---- tools/include/uapi/linux/bpf.h | 7 +++-- 4 files changed, 77 insertions(+), 19 deletions(-)