From patchwork Thu Apr 6 00:40:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Rosenberg X-Patchwork-Id: 13202725 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 C27D2C7619A for ; Thu, 6 Apr 2023 00:40:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234655AbjDFAk4 (ORCPT ); Wed, 5 Apr 2023 20:40:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234519AbjDFAkw (ORCPT ); Wed, 5 Apr 2023 20:40:52 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 81F4265AE for ; Wed, 5 Apr 2023 17:40:45 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-54c060d7cdfso17531757b3.13 for ; Wed, 05 Apr 2023 17:40:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; t=1680741644; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=x8R/SEDfqF4QrtFeRx/u2abN72cLJ7gQ42FhuO/V5K0=; b=ZCqkQYcafiAtvRvV3fHcQ/fGM6OE4T8iRV3w1fmZKzRWP42x57FdCTAbn2xhSCkS8D g7/sHITX3xpmjygzz850+hz+7Ofn3Ga29i16IQLKsvuDl/ARP0XS69IBvokQc1B/y7kj EQxUO30KM7p3z4QSgWyx3Y/XtS6cr8O8OiY23SPHPIV7y5SZucR1PBQaJFUk3nVogKey umNa/tl3tx8FFtyMktnCpJp4P21tuOkDjq4R1mI+bABEvC2PCUv4g/L2Ig8H9ne32mrO L7R0SzslBoH8PJ3dFikEKFHx3W+Uf2A5ns3c9zmYpx9t9NykulL6jkR+cNRJLm5KUmhK ofgg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680741644; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=x8R/SEDfqF4QrtFeRx/u2abN72cLJ7gQ42FhuO/V5K0=; b=60c+IZWxeExrfHt3Egtn93oeVRvMcmogFT1ItJCF633mAY8Pnf/pKozASJt/LLZPlM zW/WCp7P3Lj9BPf2mG23CNlh+SksgNZTXavwRDc76hkLDFjyX6K/A3SkZMAbTHym1lmp KH6OntJOuXIoTHdj8B4p6EFFhrX30AO+rNXuICZ+MKuvHX+qTwavJ+FnhzOpfMDdJb1i Yz5o+5szE8qds+g3nADs5MHyUk60JsDcnva/KG1CPjnm8s7ZrVrYO6Fkm1wlafZ7LVi4 yqyUJB8h7yzNd9BWAUXttDRiOr6UC+iixMYqy8Q8ztRvhlLG3CA1PY4XXXBxq5Jau2wy kV3g== X-Gm-Message-State: AAQBX9czRUeRM1EpEj54rxUcFTh1hXCYBcjMEdkmOML8/CVS2+6JqyUQ FsNNNAQnOjwB/EvCOoHK/gB5GpUlc2M= X-Google-Smtp-Source: AKy350Y+if23WZgYEhMrSezh2kGa1/V3dBjppuEeSCDz5TpXpURFDSDF0HvuDxVTPEWFxq3wS4lP9CWr3/Q= X-Received: from drosen.mtv.corp.google.com ([2620:15c:211:201:694f:f21b:c6de:aead]) (user=drosen job=sendgmr) by 2002:a25:d4c7:0:b0:b76:126b:5aa1 with SMTP id m190-20020a25d4c7000000b00b76126b5aa1mr715873ybf.8.1680741644750; Wed, 05 Apr 2023 17:40:44 -0700 (PDT) Date: Wed, 5 Apr 2023 17:40:18 -0700 In-Reply-To: <20230406004018.1439952-1-drosen@google.com> Mime-Version: 1.0 References: <20230406004018.1439952-1-drosen@google.com> X-Mailer: git-send-email 2.40.0.577.gac1e443424-goog Message-ID: <20230406004018.1439952-4-drosen@google.com> Subject: [PATCH 3/3] selftests/bpf: Test allowing NULL buffer in dynptr slice From: Daniel Rosenberg To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Jonathan Corbet , Joanne Koong , Mykola Lysenko , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-team@android.com, Daniel Rosenberg Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org bpf_dynptr_slice(_rw) no longer requires a buffer for verification. If the buffer is needed, but not present, the function will return NULL. Signed-off-by: Daniel Rosenberg --- .../testing/selftests/bpf/prog_tests/dynptr.c | 1 + .../selftests/bpf/progs/dynptr_success.c | 21 +++++++++++++++++++ 2 files changed, 22 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/dynptr.c b/tools/testing/selftests/bpf/prog_tests/dynptr.c index d176c34a7d2e..db22cad32657 100644 --- a/tools/testing/selftests/bpf/prog_tests/dynptr.c +++ b/tools/testing/selftests/bpf/prog_tests/dynptr.c @@ -20,6 +20,7 @@ static struct { {"test_ringbuf", SETUP_SYSCALL_SLEEP}, {"test_skb_readonly", SETUP_SKB_PROG}, {"test_dynptr_skb_data", SETUP_SKB_PROG}, + {"test_dynptr_skb_nobuff", SETUP_SKB_PROG}, }; static void verify_success(const char *prog_name, enum test_setup_type setup_type) diff --git a/tools/testing/selftests/bpf/progs/dynptr_success.c b/tools/testing/selftests/bpf/progs/dynptr_success.c index b2fa6c47ecc0..a059ed8d4590 100644 --- a/tools/testing/selftests/bpf/progs/dynptr_success.c +++ b/tools/testing/selftests/bpf/progs/dynptr_success.c @@ -207,3 +207,24 @@ int test_dynptr_skb_data(struct __sk_buff *skb) return 1; } + +SEC("?cgroup_skb/egress") +int test_dynptr_skb_no_buff(struct __sk_buff *skb) +{ + struct bpf_dynptr ptr; + __u64 *data; + + if (bpf_dynptr_from_skb(skb, 0, &ptr)) { + err = 1; + return 1; + } + + /* This should return NULL. SKB may require a buffer */ + data = bpf_dynptr_slice(&ptr, 0, NULL, 1); + if (data) { + err = 2; + return 1; + } + + return 1; +}