From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B82A1C10F03 for ; Tue, 19 Mar 2019 22:20:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 86A5A2183E for ; Tue, 19 Mar 2019 22:20:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="u2Brv/hd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727509AbfCSWUP (ORCPT ); Tue, 19 Mar 2019 18:20:15 -0400 Received: from mail-it1-f201.google.com ([209.85.166.201]:51443 "EHLO mail-it1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727579AbfCSWUP (ORCPT ); Tue, 19 Mar 2019 18:20:15 -0400 Received: by mail-it1-f201.google.com with SMTP id e63so433252ita.1 for ; Tue, 19 Mar 2019 15:20:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=ZgxmUh6O3jlArRZafvyJugfH/u2Yb0sWHdTxAViVUGU=; b=u2Brv/hd0MSAJK6kmTdG5AJ+0DeVrTxTiU65cwR24CQYxXL0OxvrkUMIufSBMODtru 4ja7OhoAh9jpG3UyhfiLUfQyOcDTb9QDoJGZN61AQ+lFB5vmU/qMF3QgYi7BonpTmqz7 bc9J0sJblQzxwIX2ngHz9QX0uCgLZ0JOw1bWKyDRzTvQa0Pvpy80H3o4OUAJCqygmm95 8LOmY9pM8p8/OVsdoEDufXoMCh7xijH9+QqdpYyREqRw5ZyiZISHxB7IjOINNUVugi34 CKbL6gWHvcZrntR4uOau91CFTF452NnrRmE8mmUmybSoqcFZX/P0vQp/2z0ONqLIviK9 8BwQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=ZgxmUh6O3jlArRZafvyJugfH/u2Yb0sWHdTxAViVUGU=; b=YeuhadM+7idEei+UsAlKqWkqt1LvuP6ZHZpQXTNeGoOltNH5sde4RjK/qXuWXMfuza g8Th8iT6X0H5Buy3avFmprWhT97UTEefJxTU550Ja+mtOzL5TE8KSsX/3pgruAk6yhJb mBEzWU92f6rVaXNR1NHqt9t1lLNBuLPsT4urOTJbFqoX1I+JobORAtWmUBCqp/0/hzQ+ VSKwvTMwVkO7xQaP1hvHdRoVuCTaz7UnjuzpfmdCLoX2BzJcB1dnmYqyfnr8Oox31JNm 18F8tdspkLZWaAZnorwNcvxHJtiApBhTIeRSAbu2mO2j4Dzyn3lDO3WhbcCRAv4JONEM Fs2g== X-Gm-Message-State: APjAAAVK4OjtNZPvL4S7ZBhFxcwVXCRMLoHI1fjChVw0QFv8CQcGzI/M E6PR9QONsEtfSvpBetmaprXd4q4= X-Google-Smtp-Source: APXvYqyhtvxHjo2wTlZCy4mmtWrql2ONB9uJQ7970N/qlHB8mpCP6V2zeprX4A7qoqp6bD0JuPqNvck= X-Received: by 2002:a24:3608:: with SMTP id l8mr2683213itl.35.1553034014159; Tue, 19 Mar 2019 15:20:14 -0700 (PDT) Date: Tue, 19 Mar 2019 15:19:47 -0700 In-Reply-To: <20190319221948.170441-1-sdf@google.com> Message-Id: <20190319221948.170441-9-sdf@google.com> Mime-Version: 1.0 References: <20190319221948.170441-1-sdf@google.com> X-Mailer: git-send-email 2.21.0.225.g810b269d1ac-goog Subject: [RFC bpf-next v2 8/9] selftests/bpf: add flow dissector bpf_skb_load_bytes helper test From: Stanislav Fomichev To: netdev@vger.kernel.org, bpf@vger.kernel.org Cc: davem@davemloft.net, ast@kernel.org, daniel@iogearbox.net, simon.horman@netronome.com, willemb@google.com, peterpenkov96@gmail.com, Stanislav Fomichev Content-Type: text/plain; charset="UTF-8" Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org With the per-cpu skb, we want to make sure we don't trigger any shinfo access. Add small test which tries to read the data past the packet boundary. Signed-off-by: Stanislav Fomichev --- .../prog_tests/flow_dissector_load_bytes.c | 50 +++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/flow_dissector_load_bytes.c diff --git a/tools/testing/selftests/bpf/prog_tests/flow_dissector_load_bytes.c b/tools/testing/selftests/bpf/prog_tests/flow_dissector_load_bytes.c new file mode 100644 index 000000000000..facf5734c915 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/flow_dissector_load_bytes.c @@ -0,0 +1,50 @@ +// SPDX-License-Identifier: GPL-2.0 +#include + +void test_flow_dissector_load_bytes(void) +{ + struct bpf_flow_keys flow_keys; + __u32 duration = 0, retval, size; + struct bpf_insn prog[] = { + // BPF_REG_1 - 1st argument: context + // BPF_REG_2 - 2nd argument: offset, start at last byte + 1 + BPF_MOV64_IMM(BPF_REG_2, sizeof(pkt_v4)), + // BPF_REG_3 - 3rd argument: destination, reserve byte on stack + BPF_ALU64_REG(BPF_MOV, BPF_REG_3, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, -1), + // BPF_REG_4 - 4th argument: copy one byte + BPF_MOV64_IMM(BPF_REG_4, 1), + // bpf_skb_load_bytes(ctx, sizeof(pkt_v4), ptr, 1) + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, + BPF_FUNC_skb_load_bytes), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 2), + // if (ret == 0) return BPF_DROP (2) + BPF_MOV64_IMM(BPF_REG_0, BPF_DROP), + BPF_EXIT_INSN(), + // if (ret != 0) return BPF_OK (0) + BPF_MOV64_IMM(BPF_REG_0, BPF_OK), + BPF_EXIT_INSN(), + }; + int fd, err; + + /* make sure bpf_skb_load_bytes helper doesn't cause any + * problems when used with the fake skb in the flow + * dissector (try to read past the last byte) + */ + fd = bpf_load_program(BPF_PROG_TYPE_FLOW_DISSECTOR, prog, + ARRAY_SIZE(prog), "GPL", 0, NULL, 0); + CHECK(fd < 0, + "flow_dissector-bpf_skb_load_bytes-load", + "fd %d errno %d\n", + fd, errno); + + err = bpf_prog_test_run(fd, 1, &pkt_v4, sizeof(pkt_v4), + &flow_keys, &size, &retval, &duration); + CHECK(size != sizeof(flow_keys) || err || retval != 1, + "flow_dissector-bpf_skb_load_bytes", + "err %d errno %d retval %d duration %d size %u/%lu\n", + err, errno, retval, duration, size, sizeof(flow_keys)); + + if (fd >= -1) + close(fd); +} -- 2.21.0.225.g810b269d1ac-goog