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=-23.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 37E8AC432BE for ; Tue, 24 Aug 2021 07:00:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1694161360 for ; Tue, 24 Aug 2021 07:00:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234496AbhHXHBS (ORCPT ); Tue, 24 Aug 2021 03:01:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56894 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234557AbhHXHBQ (ORCPT ); Tue, 24 Aug 2021 03:01:16 -0400 Received: from mail-wm1-x32c.google.com (mail-wm1-x32c.google.com [IPv6:2a00:1450:4864:20::32c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6916EC06175F for ; Tue, 24 Aug 2021 00:00:32 -0700 (PDT) Received: by mail-wm1-x32c.google.com with SMTP id i3so1265411wmq.3 for ; Tue, 24 Aug 2021 00:00:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ICdLCAE9F2d1J4gjoAJ7XKYwkHuUbm1vnXwFQHx40iE=; b=nNas2w1Y3fz7wuL5P1E4e+IpX/4X0yObkGSivzMK3HvusWrYcgIzL40Hiw1OWyvMvx V1TwzHfaP7mJ+ozxvftB5YmzAd8LkjY6KaXFmiwCh6GB5fCekybMW1q4mkuHQCVRgMtl 15FX6VANBhbuEthFCdEM7IOB2kxLgPBxMmlUwStsnThtykN40bdUCHxiOVq9vgzeyOqm jgylqVQ7leXHJYyQfpdtHbgQU4xpy6TsRmmdwA7qVg1UbZoKv+Rc3Qju2U2pV6ySHAZR XFN7QZ2q4Ytest0WptzCMsW4xklMPvZO+G/ZZxCEYI6qJ4aHmsALSZuTJESB93aKgoUq 7crQ== 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=ICdLCAE9F2d1J4gjoAJ7XKYwkHuUbm1vnXwFQHx40iE=; b=YFEWWnWPDcmUyMXHfMt/gdxMatdiAWJ3W4fVux2O0hCcLSn1BygSIBiHSBiHmpZZ1G cT74+nZnNkrxIgRhNUx/Do/1+LjOEOt+sJQc9KVGdgeg6NePKEG33n4bfl/ap6vsN2g4 LOYv8/8GxlqzKDiopdtaQgXDi4THXFuUYSNp8hw6g8gFMACG3lJ9R2LjYrVAyO+AB+dx LhZO/L2shtkRMUteoDMzAruxapOiUeuMHeEm+oJJ6VDHBBxmC2TdAh8w5mC/QZkITQSr qWuKhr+dynG2OVlLCHLXxsQw5QyfJp5ZaUdiraEqmitYt9AkpHy3WfZTaJVQ71mL8KpE YVWg== X-Gm-Message-State: AOAM531za0oUexmo3DxKMNgJ/WYzggGPeh3aD4s6sPyQoWeGx1xtnglY zOPUioydd5aaq493WwRzzj3QEPYIJuvmKNPKQBWU6A== X-Google-Smtp-Source: ABdhPJy985yRA4Oysjxf1QPktANY8Xl8Fwej2Qliu0YbgVY7veBPK5GUw1LEddDO8iS31szVLE9BN4bRrkY/cQdVlMw= X-Received: by 2002:a05:600c:3514:: with SMTP id h20mr2545861wmq.31.1629788430655; Tue, 24 Aug 2021 00:00:30 -0700 (PDT) MIME-Version: 1.0 References: <20210822075122.864511-1-keescook@chromium.org> <20210822075122.864511-22-keescook@chromium.org> In-Reply-To: <20210822075122.864511-22-keescook@chromium.org> From: David Gow Date: Tue, 24 Aug 2021 15:00:19 +0800 Message-ID: Subject: Re: [PATCH for-next 21/25] lib: Introduce CONFIG_TEST_MEMCPY To: Kees Cook Cc: Linux Kernel Mailing List , Rasmus Villemoes , Daniel Micay , Francis Laniel , Bart Van Assche , Linux Memory Management List , clang-built-linux@googlegroups.com, linux-hardening@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org On Sun, Aug 22, 2021 at 3:56 PM Kees Cook wrote: > > Before changing anything about memcpy(), memmove(), and memset(), add > run-time tests to check basic behaviors for any regressions. > > Signed-off-by: Kees Cook > --- Thanks for adding a KUnit test here: it's great to have better coverage of some of these basic functions! There's a name mismatch with the Kconfig entry and the Makefile, otherwise this looks good and works fine on my machine (under both UML and qemu/x86_64). It would be possible to split these tests up further if you wanted, which could be useful if there's a desire to track the individual assertion results independently. That's probably what I'd've done, but It's a matter of personal preference either way, though: the tests aren't absurdly huge or over-complicated as-is. Cheers, -- David > MAINTAINERS | 9 ++ > lib/Kconfig.debug | 11 ++ > lib/Makefile | 1 + > lib/test_memcpy.c | 265 ++++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 286 insertions(+) > create mode 100644 lib/test_memcpy.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 6c8be735cc91..e3ffd4bdc24f 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -7248,6 +7248,15 @@ L: netdev@vger.kernel.org > S: Maintained > F: drivers/net/ethernet/nvidia/* > > +FORTIFY_SOURCE > +M: Kees Cook > +L: linux-hardening@vger.kernel.org > +S: Supported > +F: include/linux/fortify-string.h > +F: lib/test_fortify/* > +F: scripts/test_fortify.sh > +K: \b__NO_FORTIFY\b > + Do you want this to be part of the memcpy() KUnit test commit, or is it better suited in one of the changes to the actual fortify stuff? > FPGA DFL DRIVERS > M: Wu Hao > R: Tom Rix > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug > index 831212722924..9199be57ba2a 100644 > --- a/lib/Kconfig.debug > +++ b/lib/Kconfig.debug > @@ -2467,6 +2467,17 @@ config RATIONAL_KUNIT_TEST > > If unsure, say N. > > +config MEMCPY_KUNIT_TEST > + tristate "Test memcpy(), memmove(), and memset() functions at runtime" if !KUNIT_ALL_TESTS > + depends on KUNIT > + default KUNIT_ALL_TESTS > + help > + Builds unit tests for memcpy(), memmove(), and memset() functions. > + For more information on KUnit and unit tests in general please refer > + to the KUnit documentation in Documentation/dev-tools/kunit/. > + > + If unsure, say N. > + > config TEST_UDELAY > tristate "udelay test driver" > help > diff --git a/lib/Makefile b/lib/Makefile > index bd17c2bf43e1..8a4c8bdb38a2 100644 > --- a/lib/Makefile > +++ b/lib/Makefile > @@ -77,6 +77,7 @@ obj-$(CONFIG_TEST_MIN_HEAP) += test_min_heap.o > obj-$(CONFIG_TEST_LKM) += test_module.o > obj-$(CONFIG_TEST_VMALLOC) += test_vmalloc.o > obj-$(CONFIG_TEST_OVERFLOW) += test_overflow.o > +obj-$(CONFIG_TEST_MEMCPY) += test_memcpy.o This doesn't match CONFIG_MEMCPY_KUNIT_TEST above, so the test is never compiled in. > obj-$(CONFIG_TEST_RHASHTABLE) += test_rhashtable.o > obj-$(CONFIG_TEST_SORT) += test_sort.o > obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o > diff --git a/lib/test_memcpy.c b/lib/test_memcpy.c > new file mode 100644 > index 000000000000..ec546cec883e > --- /dev/null > +++ b/lib/test_memcpy.c > @@ -0,0 +1,265 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Test cases for memcpy(), memmove(), and memset(). > + */ > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct some_bytes { > + union { > + u8 data[32]; > + struct { > + u32 one; > + u16 two; > + u8 three; > + /* 1 byte hole */ > + u32 four[4]; > + }; > + }; > +}; > + > +#define check(instance, v) do { \ > + int i; \ > + BUILD_BUG_ON(sizeof(instance.data) != 32); \ > + for (i = 0; i < sizeof(instance.data); i++) { \ > + KUNIT_ASSERT_EQ_MSG(test, instance.data[i], v, \ > + "line %d: '%s' not initialized to 0x%02x @ %d (saw 0x%02x)\n", \ > + __LINE__, #instance, v, i, instance.data[i]); \ > + } \ > +} while (0) > + > +#define compare(name, one, two) do { \ > + int i; \ > + BUILD_BUG_ON(sizeof(one) != sizeof(two)); \ > + for (i = 0; i < sizeof(one); i++) { \ > + KUNIT_EXPECT_EQ_MSG(test, one.data[i], two.data[i], \ > + "line %d: %s.data[%d] (0x%02x) != %s.data[%d] (0x%02x)\n", \ > + __LINE__, #one, i, one.data[i], #two, i, two.data[i]); \ > + } \ > + kunit_info(test, "ok: " TEST_OP "() " name "\n"); \ > +} while (0) > + > +static void memcpy_test(struct kunit *test) > +{ > +#define TEST_OP "memcpy" > + struct some_bytes control = { > + .data = { 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, > + 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, > + 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, > + 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, > + }, > + }; > + struct some_bytes zero = { }; > + struct some_bytes middle = { > + .data = { 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, > + 0x20, 0x20, 0x20, 0x20, 0x00, 0x00, 0x00, 0x00, > + 0x00, 0x00, 0x00, 0x20, 0x20, 0x20, 0x20, 0x20, > + 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, > + }, > + }; > + struct some_bytes three = { > + .data = { 0x00, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, > + 0x20, 0x00, 0x00, 0x20, 0x20, 0x20, 0x20, 0x20, > + 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, > + 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, > + }, > + }; > + struct some_bytes dest = { }; > + int count; > + u8 *ptr; > + > + /* Verify static initializers. */ > + check(control, 0x20); > + check(zero, 0); > + compare("static initializers", dest, zero); > + > + /* Verify assignment. */ > + dest = control; > + compare("direct assignment", dest, control); > + > + /* Verify complete overwrite. */ > + memcpy(dest.data, zero.data, sizeof(dest.data)); > + compare("complete overwrite", dest, zero); > + > + /* Verify middle overwrite. */ > + dest = control; > + memcpy(dest.data + 12, zero.data, 7); > + compare("middle overwrite", dest, middle); > + > + /* Verify argument side-effects aren't repeated. */ > + dest = control; > + ptr = dest.data; > + count = 1; > + memcpy(ptr++, zero.data, count++); > + ptr += 8; > + memcpy(ptr++, zero.data, count++); > + compare("argument side-effects", dest, three); > +#undef TEST_OP > +} > + > +static void memmove_test(struct kunit *test) > +{ > +#define TEST_OP "memmove" > + struct some_bytes control = { > + .data = { 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + }, > + }; > + struct some_bytes zero = { }; > + struct some_bytes middle = { > + .data = { 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + 0x99, 0x99, 0x99, 0x99, 0x00, 0x00, 0x00, 0x00, > + 0x00, 0x00, 0x00, 0x99, 0x99, 0x99, 0x99, 0x99, > + 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + }, > + }; > + struct some_bytes five = { > + .data = { 0x00, 0x00, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + 0x99, 0x99, 0x00, 0x00, 0x00, 0x99, 0x99, 0x99, > + 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + }, > + }; > + struct some_bytes overlap = { > + .data = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, > + 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, > + 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + }, > + }; > + struct some_bytes overlap_expected = { > + .data = { 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x04, 0x07, > + 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, > + 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, 0x99, > + }, > + }; > + struct some_bytes dest = { }; > + int count; > + u8 *ptr; > + > + /* Verify static initializers. */ > + check(control, 0x99); > + check(zero, 0); > + compare("static initializers", zero, dest); > + > + /* Verify assignment. */ > + dest = control; > + compare("direct assignment", dest, control); > + > + /* Verify complete overwrite. */ > + memmove(dest.data, zero.data, sizeof(dest.data)); > + compare("complete overwrite", dest, zero); > + > + /* Verify middle overwrite. */ > + dest = control; > + memmove(dest.data + 12, zero.data, 7); > + compare("middle overwrite", dest, middle); > + > + /* Verify argument side-effects aren't repeated. */ > + dest = control; > + ptr = dest.data; > + count = 2; > + memmove(ptr++, zero.data, count++); > + ptr += 9; > + memmove(ptr++, zero.data, count++); > + compare("argument side-effects", dest, five); > + > + /* Verify overlapping overwrite is correct. */ > + ptr = &overlap.data[2]; > + memmove(ptr, overlap.data, 5); > + compare("overlapping write", overlap, overlap_expected); > +#undef TEST_OP > +} > + > +static void memset_test(struct kunit *test) > +{ > +#define TEST_OP "memset" > + struct some_bytes control = { > + .data = { 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, > + 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, > + 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, > + 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, > + }, > + }; > + struct some_bytes complete = { > + .data = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, > + }, > + }; > + struct some_bytes middle = { > + .data = { 0x30, 0x30, 0x30, 0x30, 0x31, 0x31, 0x31, 0x31, > + 0x31, 0x31, 0x31, 0x31, 0x31, 0x31, 0x31, 0x31, > + 0x31, 0x31, 0x31, 0x31, 0x30, 0x30, 0x30, 0x30, > + 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, > + }, > + }; > + struct some_bytes three = { > + .data = { 0x60, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, > + 0x30, 0x61, 0x61, 0x30, 0x30, 0x30, 0x30, 0x30, > + 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, > + 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, > + }, > + }; > + struct some_bytes dest = { }; > + int count, value; > + u8 *ptr; > + > + /* Verify static initializers. */ > + check(control, 0x30); > + check(dest, 0); > + > + /* Verify assignment. */ > + dest = control; > + compare("direct assignment", dest, control); > + > + /* Verify complete overwrite. */ > + memset(dest.data, 0xff, sizeof(dest.data)); > + compare("complete overwrite", dest, complete); > + > + /* Verify middle overwrite. */ > + dest = control; > + memset(dest.data + 4, 0x31, 16); > + compare("middle overwrite", dest, middle); > + > + /* Verify argument side-effects aren't repeated. */ > + dest = control; > + ptr = dest.data; > + value = 0x60; > + count = 1; > + memset(ptr++, value++, count++); > + ptr += 8; > + memset(ptr++, value++, count++); > + compare("argument side-effects", dest, three); > +#undef TEST_OP > +} > + > +static struct kunit_case memcpy_test_cases[] = { > + KUNIT_CASE(memset_test), > + KUNIT_CASE(memcpy_test), > + KUNIT_CASE(memmove_test), > + {} > +}; > + > +static struct kunit_suite memcpy_test_suite = { > + .name = "memcpy-test", It may be better to just name the suite "memcpy", since -- by definition -- it's a test if it's a KUnit test suite. > + .test_cases = memcpy_test_cases, > +}; > + > +kunit_test_suite(memcpy_test_suite); > + > +MODULE_LICENSE("GPL"); > -- > 2.30.2 >