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=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 4B028C4320A for ; Fri, 13 Aug 2021 23:30:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 297BE610F7 for ; Fri, 13 Aug 2021 23:30:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235523AbhHMXbJ (ORCPT ); Fri, 13 Aug 2021 19:31:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48318 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235330AbhHMXbJ (ORCPT ); Fri, 13 Aug 2021 19:31:09 -0400 Received: from mail-yb1-xb2a.google.com (mail-yb1-xb2a.google.com [IPv6:2607:f8b0:4864:20::b2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 902F1C061756; Fri, 13 Aug 2021 16:30:41 -0700 (PDT) Received: by mail-yb1-xb2a.google.com with SMTP id z5so21846456ybj.2; Fri, 13 Aug 2021 16:30:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=fbF5MrkpdZcrtC+qEDXqiSIRzXw6E9ONxnt1fjH3g3c=; b=tFM5k4D+n6Z3fUdxDmEUl7609+nxwRUyfX/bsXhQ0SSv6Kez5y7nAETLdfF+5+Wiow CCcaX3SXFISQwE9Hi6SezqIC4oHkDqTb5N5v7VZaByHWERNR3fuTyvmU/E44z8iVzwHk BhaI7HMdJ2j3Li5ZpLUBBDAWQH3EPpm0/rt1POcpj9Rx7t7wFhjEKk60gBq7B/ZBIhm2 DSfv31MeMcwN1jbAcWMLollrDnGsmav9Mke11S9h1WYTgVVsytW17xC+dNTe27VsQMLM 7EW9iwPVBns+68A7VjDanhqcE00HarrxbwLNI8IFsXoW18gwOilWwvoi0gBOo7EQM8M4 m1uQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=fbF5MrkpdZcrtC+qEDXqiSIRzXw6E9ONxnt1fjH3g3c=; b=WhDMeDMu2dJhbIwGku85CAvHWx3eCPogljZPeRQEA/8u8Z0LMmvUAuVfESKXm0iShD 3qvV0PchLwD8vklEY02N+JxnPqeXvy3/lvbD44sa4VGmdRqwqs0VfCSSMKvNnTpV1hJU Nc5Es8pMntQ879fDoiA/7qAa/bzEtEqmV+IGxDm28ND7NqrwSu9mwE/sFdydtaEtUxK/ L/NgbzfUk5cZj1xq3gVlAbSjfjOR5/E3J519C6uoab9Njc03tIAS+ZxFNAMEVyXSnrKy PM53C8oA0Mnjlhc4HppNJRbCc9eT59rY8JXBlCmXbgG8NrU/YWi0rnZLdcq4phhOJzsO FaqQ== X-Gm-Message-State: AOAM530LyK8/o6lLXWPqk4mJs+NPqgT3XGcEZAWGFyas1Wm5AiWk5c/s MBW3HzkFOyziYM1KrqatECNm9JrUQxm310hkF2E= X-Google-Smtp-Source: ABdhPJwi/hDB8mnYPfUy2EaFZPPmnJqJyMkpTCTeb8P2bLl8X/f9WAL4+6e5RrWksp0ZkD7ZTD0d76gDdyv4436wDJY= X-Received: by 2002:a25:b21f:: with SMTP id i31mr5862051ybj.403.1628897440789; Fri, 13 Aug 2021 16:30:40 -0700 (PDT) MIME-Version: 1.0 References: <20210812164557.79046-1-kuniyu@amazon.co.jp> <20210812164557.79046-5-kuniyu@amazon.co.jp> In-Reply-To: From: Andrii Nakryiko Date: Fri, 13 Aug 2021 16:30:29 -0700 Message-ID: Subject: Re: [PATCH v5 bpf-next 4/4] selftest/bpf: Extend the bpf_snprintf() test for "%c". To: Kuniyuki Iwashima Cc: "David S. Miller" , Jakub Kicinski , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Benjamin Herrenschmidt , Kuniyuki Iwashima , bpf , Networking Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, Aug 13, 2021 at 4:28 PM Andrii Nakryiko wrote: > > On Thu, Aug 12, 2021 at 9:47 AM Kuniyuki Iwashima wrote: > > > > This patch adds a "positive" pattern for "%c", which intentionally uses a > > __u32 value (0x64636261, "dbca") to print a single character "a". If the > > implementation went wrong, other 3 bytes might show up as the part of the > > latter "%+05s". > > > > Also, this patch adds two "negative" patterns for wide character. > > > > Signed-off-by: Kuniyuki Iwashima > > --- > > tools/testing/selftests/bpf/prog_tests/snprintf.c | 4 +++- > > tools/testing/selftests/bpf/progs/test_snprintf.c | 7 ++++--- > > 2 files changed, 7 insertions(+), 4 deletions(-) > > > > diff --git a/tools/testing/selftests/bpf/prog_tests/snprintf.c b/tools/testing/selftests/bpf/prog_tests/snprintf.c > > index dffbcaa1ec98..f77d7def7fed 100644 > > --- a/tools/testing/selftests/bpf/prog_tests/snprintf.c > > +++ b/tools/testing/selftests/bpf/prog_tests/snprintf.c > > @@ -19,7 +19,7 @@ > > #define EXP_ADDR_OUT "0000000000000000 ffff00000add4e55 " > > #define EXP_ADDR_RET sizeof(EXP_ADDR_OUT "unknownhashedptr") > > > > -#define EXP_STR_OUT "str1 longstr" > > +#define EXP_STR_OUT "str1 a longstr" > > #define EXP_STR_RET sizeof(EXP_STR_OUT) > > > > #define EXP_OVER_OUT "%over" > > @@ -114,6 +114,8 @@ void test_snprintf_negative(void) > > ASSERT_ERR(load_single_snprintf("%"), "invalid specifier 3"); > > ASSERT_ERR(load_single_snprintf("%12345678"), "invalid specifier 4"); > > ASSERT_ERR(load_single_snprintf("%--------"), "invalid specifier 5"); > > + ASSERT_ERR(load_single_snprintf("%lc"), "invalid specifier 6"); > > + ASSERT_ERR(load_single_snprintf("%llc"), "invalid specifier 7"); > > ASSERT_ERR(load_single_snprintf("\x80"), "non ascii character"); > > ASSERT_ERR(load_single_snprintf("\x1"), "non printable character"); > > } > > diff --git a/tools/testing/selftests/bpf/progs/test_snprintf.c b/tools/testing/selftests/bpf/progs/test_snprintf.c > > index e2ad26150f9b..afc2c583125b 100644 > > --- a/tools/testing/selftests/bpf/progs/test_snprintf.c > > +++ b/tools/testing/selftests/bpf/progs/test_snprintf.c > > @@ -40,6 +40,7 @@ int handler(const void *ctx) > > /* Convenient values to pretty-print */ > > const __u8 ex_ipv4[] = {127, 0, 0, 1}; > > const __u8 ex_ipv6[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}; > > + const __u32 chr1 = 0x64636261; /* dcba */ > > static const char str1[] = "str1"; > > static const char longstr[] = "longstr"; > > > > @@ -59,9 +60,9 @@ int handler(const void *ctx) > > /* Kernel pointers */ > > addr_ret = BPF_SNPRINTF(addr_out, sizeof(addr_out), "%pK %px %p", > > 0, 0xFFFF00000ADD4E55, 0xFFFF00000ADD4E55); > > - /* Strings embedding */ > > - str_ret = BPF_SNPRINTF(str_out, sizeof(str_out), "%s %+05s", > > - str1, longstr); > > + /* Strings and single-byte character embedding */ > > + str_ret = BPF_SNPRINTF(str_out, sizeof(str_out), "%s % 9c %+05s", > > + str1, chr1, longstr); Can you also add tests for %+2c, %-3c, %04c, %0c? Think outside the box ;) > > > Why this hackery with __u32? You are making an endianness assumption > (it will break on big-endian), and you'd never write real code like > that. Just pass 'a', what's wrong with that? > > > /* Overflow */ > > over_ret = BPF_SNPRINTF(over_out, sizeof(over_out), "%%overflow"); > > /* Padding of fixed width numbers */ > > -- > > 2.30.2 > >