From patchwork Tue Jun 23 03:22:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 1314858 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=reject dis=none) header.from=fb.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.a=rsa-sha256 header.s=facebook header.b=ofhWpTG1; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49rWmx6Y0Dz9sRf for ; Tue, 23 Jun 2020 13:22:41 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731909AbgFWDWk (ORCPT ); Mon, 22 Jun 2020 23:22:40 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:1462 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731803AbgFWDWj (ORCPT ); Mon, 22 Jun 2020 23:22:39 -0400 Received: from pps.filterd (m0044010.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 05N3Fseg025247 for ; Mon, 22 Jun 2020 20:22:39 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=jGEd8Qm8VYhVNHEomGb8YOl2uMOuG8pc+dweqhO0500=; b=ofhWpTG1CQ1SCDp2xE+HKKhUiZNPvpmE+eKQJ1TgtcSGYkSiiYkIoa5hqwtigUQ7fcBq HWm4JF4hPmpAYCXFlj17FOzGA6CtfC51veduL8jXydzqAWn+rlED6eFXQpsY7W6VR37T VWe5zL9YZMRejFAJf2nyVAe5xT7pidDAwHA= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 31t2a2gx9x-3 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 22 Jun 2020 20:22:38 -0700 Received: from intmgw003.08.frc2.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Mon, 22 Jun 2020 20:22:36 -0700 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id 9DD882EC33D1; Mon, 22 Jun 2020 20:22:29 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Andrii Nakryiko Smtp-Origin-Hostname: devbig012.ftw2.facebook.com To: , , , , CC: , , Andrii Nakryiko Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH v3 bpf-next 3/3] selftests/bpf: add variable-length data concat pattern less than test Date: Mon, 22 Jun 2020 20:22:23 -0700 Message-ID: <20200623032224.4020118-3-andriin@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200623032224.4020118-1-andriin@fb.com> References: <20200623032224.4020118-1-andriin@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.216, 18.0.687 definitions=2020-06-22_16:2020-06-22,2020-06-22 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 lowpriorityscore=0 adultscore=0 priorityscore=1501 phishscore=0 malwarescore=0 clxscore=1015 mlxlogscore=534 bulkscore=0 cotscore=-2147483648 mlxscore=0 impostorscore=0 suspectscore=8 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2006230024 X-FB-Internal: deliver Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org From: John Fastabend Extend original variable-length tests with a case to catch a common existing pattern of testing for < 0 for errors. Note because verifier also tracks upper bounds and we know it can not be greater than MAX_LEN here we can skip upper bound check. In ALU64 enabled compilation converting from long->int return types in probe helpers results in extra instruction pattern, <<= 32, s >>= 32. The trade-off is the non-ALU64 case works. If you really care about every extra insn (XDP case?) then you probably should be using original int type. In addition adding a sext insn to bpf might help the verifier in the general case to avoid these types of tricks. Signed-off-by: John Fastabend Signed-off-by: Andrii Nakryiko --- .../testing/selftests/bpf/prog_tests/varlen.c | 12 ++++ .../testing/selftests/bpf/progs/test_varlen.c | 70 +++++++++++++++++-- 2 files changed, 78 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/varlen.c b/tools/testing/selftests/bpf/prog_tests/varlen.c index 7533565e096d..c75525eab02c 100644 --- a/tools/testing/selftests/bpf/prog_tests/varlen.c +++ b/tools/testing/selftests/bpf/prog_tests/varlen.c @@ -51,6 +51,18 @@ void test_varlen(void) CHECK_VAL(data->total2, size1 + size2); CHECK(memcmp(data->payload2, exp_str, size1 + size2), "content_check", "doesn't match!"); + + CHECK_VAL(data->payload3_len1, size1); + CHECK_VAL(data->payload3_len2, size2); + CHECK_VAL(data->total3, size1 + size2); + CHECK(memcmp(data->payload3, exp_str, size1 + size2), "content_check", + "doesn't match!"); + + CHECK_VAL(data->payload4_len1, size1); + CHECK_VAL(data->payload4_len2, size2); + CHECK_VAL(data->total4, size1 + size2); + CHECK(memcmp(data->payload4, exp_str, size1 + size2), "content_check", + "doesn't match!"); cleanup: test_varlen__destroy(skel); } diff --git a/tools/testing/selftests/bpf/progs/test_varlen.c b/tools/testing/selftests/bpf/progs/test_varlen.c index 09691852debf..cd4b72c55dfe 100644 --- a/tools/testing/selftests/bpf/progs/test_varlen.c +++ b/tools/testing/selftests/bpf/progs/test_varlen.c @@ -26,8 +26,18 @@ int payload2_len2 = -1; int total2 = -1; char payload2[MAX_LEN + MAX_LEN] = { 1 }; +int payload3_len1 = -1; +int payload3_len2 = -1; +int total3= -1; +char payload3[MAX_LEN + MAX_LEN] = { 1 }; + +int payload4_len1 = -1; +int payload4_len2 = -1; +int total4= -1; +char payload4[MAX_LEN + MAX_LEN] = { 1 }; + SEC("raw_tp/sys_enter") -int handler64(void *regs) +int handler64_unsigned(void *regs) { int pid = bpf_get_current_pid_tgid() >> 32; void *payload = payload1; @@ -54,8 +64,34 @@ int handler64(void *regs) return 0; } -SEC("tp_btf/sys_enter") -int handler32(void *regs) +SEC("raw_tp/sys_exit") +int handler64_signed(void *regs) +{ + int pid = bpf_get_current_pid_tgid() >> 32; + void *payload = payload3; + long len; + + /* ignore irrelevant invocations */ + if (test_pid != pid || !capture) + return 0; + + len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in1[0]); + if (len >= 0) { + payload += len; + payload3_len1 = len; + } + len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in2[0]); + if (len >= 0) { + payload += len; + payload3_len2 = len; + } + total3 = payload - (void *)payload3; + + return 0; +} + +SEC("tp/raw_syscalls/sys_enter") +int handler32_unsigned(void *regs) { int pid = bpf_get_current_pid_tgid() >> 32; void *payload = payload2; @@ -82,7 +118,33 @@ int handler32(void *regs) return 0; } -SEC("tp_btf/sys_exit") +SEC("tp/raw_syscalls/sys_exit") +int handler32_signed(void *regs) +{ + int pid = bpf_get_current_pid_tgid() >> 32; + void *payload = payload4; + int len; + + /* ignore irrelevant invocations */ + if (test_pid != pid || !capture) + return 0; + + len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in1[0]); + if (len >= 0) { + payload += len; + payload4_len1 = len; + } + len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in2[0]); + if (len >= 0) { + payload += len; + payload4_len2 = len; + } + total4 = payload - (void *)payload4; + + return 0; +} + +SEC("tp/syscalls/sys_exit_getpid") int handler_exit(void *regs) { long bla;