From patchwork Wed May 25 03:27:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: shaozhengchao X-Patchwork-Id: 12860696 X-Patchwork-Delegate: bpf@iogearbox.net 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 F27ABC433EF for ; Wed, 25 May 2022 03:27:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240183AbiEYD1l (ORCPT ); Tue, 24 May 2022 23:27:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46432 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235350AbiEYD1h (ORCPT ); Tue, 24 May 2022 23:27:37 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F152C77F28; Tue, 24 May 2022 20:27:35 -0700 (PDT) Received: from canpemm100007.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4L7Ggt3dF5zhXZW; Wed, 25 May 2022 11:26:34 +0800 (CST) Received: from dggpeml500026.china.huawei.com (7.185.36.106) by canpemm100007.china.huawei.com (7.192.105.181) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 25 May 2022 11:27:33 +0800 Received: from dggpeml500026.china.huawei.com ([7.185.36.106]) by dggpeml500026.china.huawei.com ([7.185.36.106]) with mapi id 15.01.2375.024; Wed, 25 May 2022 11:27:33 +0800 From: shaozhengchao To: "bpf@vger.kernel.org" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "ast@kernel.org" , "daniel@iogearbox.net" , "davem@davemloft.net" , "kuba@kernel.org" , "hawk@kernel.org" , "john.fastabend@gmail.com" , "andrii@kernel.org" , "kafai@fb.com" , "songliubraving@fb.com" , "yhs@fb.com" , "kpsingh@kernel.org" , =?utf-8?q?Toke_H=C3=B8iland-J?= =?utf-8?q?=C3=B8rgensen?= CC: "weiyongjun (A)" , yuehaibing Subject: =?utf-8?q?=E7=AD=94=E5=A4=8D=3A_=5BPATCH_v3=2Cbpf-next=5D_samples/b?= =?utf-8?q?pf=3A_check_detach_prog_exist_or_not_in_xdp=5Ffwd?= Thread-Topic: [PATCH v3,bpf-next] samples/bpf: check detach prog exist or not in xdp_fwd Thread-Index: AQHYbMwX/T6Yw+1VQUW5SPSwZfp9Ia0u9MSQ Date: Wed, 25 May 2022 03:27:33 +0000 Message-ID: References: <20220521043509.389007-1-shaozhengchao@huawei.com> In-Reply-To: <20220521043509.389007-1-shaozhengchao@huawei.com> Accept-Language: zh-CN, en-US Content-Language: zh-CN X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.174.178.66] MIME-Version: 1.0 X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org -----邮件原件----- 发件人: shaozhengchao 发送时间: 2022年5月21日 12:35 收件人: bpf@vger.kernel.org; netdev@vger.kernel.org; linux-kernel@vger.kernel.org; ast@kernel.org; daniel@iogearbox.net; davem@davemloft.net; kuba@kernel.org; hawk@kernel.org; john.fastabend@gmail.com; andrii@kernel.org; kafai@fb.com; songliubraving@fb.com; yhs@fb.com; kpsingh@kernel.org 抄送: weiyongjun (A) ; shaozhengchao ; yuehaibing 主题: [PATCH v3,bpf-next] samples/bpf: check detach prog exist or not in xdp_fwd Before detach the prog, we should check detach prog exist or not. Signed-off-by: Zhengchao Shao --- samples/bpf/xdp_fwd_user.c | 59 ++++++++++++++++++++++++++++++++------ 1 file changed, 50 insertions(+), 9 deletions(-) -- 2.17.1 Hi Toke, Do you have any more feedback? Does it look better to you now? diff --git a/samples/bpf/xdp_fwd_user.c b/samples/bpf/xdp_fwd_user.c index 1828487bae9a..03a50f64e99a 100644 --- a/samples/bpf/xdp_fwd_user.c +++ b/samples/bpf/xdp_fwd_user.c @@ -47,17 +47,58 @@ static int do_attach(int idx, int prog_fd, int map_fd, const char *name) return err; } -static int do_detach(int idx, const char *name) +static int do_detach(int ifindex, const char *ifname, const char +*app_name) { - int err; + LIBBPF_OPTS(bpf_xdp_attach_opts, opts); + struct bpf_prog_info prog_info = {}; + char prog_name[BPF_OBJ_NAME_LEN]; + __u32 info_len, curr_prog_id; + int prog_fd; + int err = 1; + + if (bpf_xdp_query_id(ifindex, xdp_flags, &curr_prog_id)) { + printf("ERROR: bpf_xdp_query_id failed (%s)\n", + strerror(errno)); + return err; + } + + if (!curr_prog_id) { + printf("ERROR: flags(0x%x) xdp prog is not attached to %s\n", + xdp_flags, ifname); + return err; + } - err = bpf_xdp_detach(idx, xdp_flags, NULL); - if (err < 0) - printf("ERROR: failed to detach program from %s\n", name); + info_len = sizeof(prog_info); + prog_fd = bpf_prog_get_fd_by_id(curr_prog_id); + if (prog_fd < 0) { + printf("ERROR: bpf_prog_get_fd_by_id failed (%s)\n", + strerror(errno)); + return err; + } + + err = bpf_obj_get_info_by_fd(prog_fd, &prog_info, &info_len); + if (err) { + printf("ERROR: bpf_obj_get_info_by_fd failed (%s)\n", + strerror(errno)); + return err; + } + snprintf(prog_name, sizeof(prog_name), "%s_prog", app_name); + prog_name[BPF_OBJ_NAME_LEN - 1] = '\0'; + + if (strcmp(prog_info.name, prog_name)) { + printf("ERROR: %s isn't attached to %s\n", app_name, ifname); + err = 1; + } else { + opts.old_prog_fd = prog_fd; + err = bpf_xdp_detach(ifindex, xdp_flags, &opts); + if (err < 0) + printf("ERROR: failed to detach program from %s (%s)\n", + ifname, strerror(errno)); + /* TODO: Remember to cleanup map, when adding use of shared map + * bpf_map_delete_elem((map_fd, &idx); + */ + } - /* TODO: Remember to cleanup map, when adding use of shared map - * bpf_map_delete_elem((map_fd, &idx); - */ return err; } @@ -169,7 +210,7 @@ int main(int argc, char **argv) return 1; } if (!attach) { - err = do_detach(idx, argv[i]); + err = do_detach(idx, argv[i], prog_name); if (err) ret = err; } else {