From patchwork Mon Mar 6 03:31:17 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xu Kuohai X-Patchwork-Id: 13160169 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 DB2B2C61DA4 for ; Sun, 5 Mar 2023 14:31:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229766AbjCEObo (ORCPT ); Sun, 5 Mar 2023 09:31:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229780AbjCEObn (ORCPT ); Sun, 5 Mar 2023 09:31:43 -0500 Received: from dggsgout11.his.huawei.com (unknown [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7EF9212BE5; Sun, 5 Mar 2023 06:31:34 -0800 (PST) Received: from mail02.huawei.com (unknown [172.30.67.153]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4PV4000sHrz4f3jLk; Sun, 5 Mar 2023 22:31:28 +0800 (CST) Received: from k01.huawei.com (unknown [10.67.174.197]) by APP4 (Coremail) with SMTP id gCh0CgBnF6vApwRkTwIvEw--.13658S2; Sun, 05 Mar 2023 22:31:29 +0800 (CST) From: Xu Kuohai To: bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@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 , Mykola Lysenko , Shuah Khan Subject: [PATCH bpf-next 0/2] bpf: add bound tracking for BPF_MOD Date: Sun, 5 Mar 2023 22:31:17 -0500 Message-Id: <20230306033119.2634976-1-xukuohai@huaweicloud.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-CM-TRANSID: gCh0CgBnF6vApwRkTwIvEw--.13658S2 X-Coremail-Antispam: 1UD129KBjvdXoWruFyfKr1UXF1kWrW7Cw47CFg_yoW3WrcEya 92vas0vFsxtFn3Za9a9F17XFWUCw4UKry5JFsFgFW7XFykAryY9Fn5CrnYqa4DWayrJ39r JrnxtaykArnI9jkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbskYFVCjjxCrM7AC8VAFwI0_Gr0_Xr1l1xkIjI8I6I8E6xAIw20E Y4v20xvaj40_Wr0E3s1l1IIY67AEw4v_Jr0_Jr4l87I20VAvwVAaII0Ic2I_Grv_XF1l8c AvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWDJVCq 3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Gc CE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxI r21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1Y6r17McIj6I8E87 Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIE c7CjxVA2Y2ka0xkIwI1l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2 IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v2 6r4a6rW5MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2 IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWrJr0_WFyUJwCI42IY6I8E 87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73Uj IFyTuYvjxUcgyCDUUUU X-CM-SenderInfo: 50xn30hkdlqx5xdzvxpfor3voofrz/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net From: Xu Kuohai dst_reg is marked as unknown when BPF_MOD instruction is verified, causing the following bpf prog to be incorrectly rejected. 0: r0 = 0 1: r0 %= 10 // r0 is marked as unknown 2: r1 = 0 3: r1 += 1 4: if r1 < r0 goto pc-2 // verifier concludes the loop is unbounded 5: exit To teach verifier to accept the above prog, this series adds bound tracking for BPF_MOD. Xu Kuohai (2): bpf: add bound tracking for BPF_MOD selftests/bpf: check if verifier tracks dst_reg bound for BPF_MOD kernel/bpf/verifier.c | 98 +++++++- tools/testing/selftests/bpf/verifier/mod.c | 247 +++++++++++++++++++++ 2 files changed, 340 insertions(+), 5 deletions(-) create mode 100644 tools/testing/selftests/bpf/verifier/mod.c