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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id o18-20020a170903301200b0015e8d4eb2ddsm6904392pla.295.2022.05.03.18.47.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 May 2022 18:47:35 -0700 (PDT) From: Kees Cook To: "Gustavo A . R . Silva" Cc: Kees Cook , David Gow , kunit-dev@googlegroups.com, Alexei Starovoitov , alsa-devel@alsa-project.org, Al Viro , Andrew Gabbasov , Andrew Morton , Andy Gross , Andy Lavr , Arend van Spriel , Baowen Zheng , Bjorn Andersson , Boris Ostrovsky , Bradley Grove , brcm80211-dev-list.pdl@broadcom.com, Christian Brauner , =?utf-8?q?Christian_G=C3=B6ttsche?= , Christian Lamparter , Chris Zankel , Cong Wang , Daniel Axtens , Daniel Vetter , Dan Williams , David Howells , "David S. Miller" , Dennis Dalessandro , devicetree@vger.kernel.org, Dexuan Cui , Dmitry Kasatkin , Eli Cohen , Eric Dumazet , Eric Paris , Eugeniu Rosca , Felipe Balbi , Francis Laniel , Frank Rowand , Franky Lin , Greg Kroah-Hartman , Gregory Greenman , Guenter Roeck , Haiyang Zhang , Hante Meuleman , Herbert Xu , Hulk Robot , Jakub Kicinski , "James E.J. Bottomley" , James Morris , Jarkko Sakkinen , Jaroslav Kysela , Jason Gunthorpe , Jens Axboe , Johan Hedberg , Johannes Berg , Johannes Berg , John Keeping , Juergen Gross , Kalle Valo , Keith Packard , keyrings@vger.kernel.org, Kuniyuki Iwashima , "K. Y. Srinivasan" , Lars-Peter Clausen , Lee Jones , Leon Romanovsky , Liam Girdwood , linux1394-devel@lists.sourceforge.net, linux-afs@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-bluetooth@vger.kernel.org, linux-hardening@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-integrity@vger.kernel.org, linux-rdma@vger.kernel.org, linux-scsi@vger.kernel.org, linux-security-module@vger.kernel.org, linux-usb@vger.kernel.org, linux-wireless@vger.kernel.org, linux-xtensa@linux-xtensa.org, llvm@lists.linux.dev, Loic Poulain , Louis Peens , Luca Coelho , Luiz Augusto von Dentz , Marc Dionne , Marcel Holtmann , Mark Brown , "Martin K. Petersen" , Max Filippov , Mimi Zohar , Muchun Song , Nathan Chancellor , netdev@vger.kernel.org, Nick Desaulniers , =?utf-8?q?Nuno_S=C3=A1?= , Paolo Abeni , Paul Moore , Rich Felker , Rob Herring , Russell King , selinux@vger.kernel.org, "Serge E. Hallyn" , SHA-cyfmac-dev-list@infineon.com, Simon Horman , Stefano Stabellini , Stefan Richter , Steffen Klassert , Stephen Hemminger , Stephen Smalley , Tadeusz Struk , Takashi Iwai , Tom Rix , Udipto Goswami , Vincenzo Frascino , wcn36xx@lists.infradead.org, Wei Liu , xen-devel@lists.xenproject.org, Xiu Jianfeng , Yang Yingliang Subject: [PATCH 03/32] flex_array: Add Kunit tests Date: Tue, 3 May 2022 18:44:12 -0700 Message-Id: <20220504014440.3697851-4-keescook@chromium.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220504014440.3697851-1-keescook@chromium.org> References: <20220504014440.3697851-1-keescook@chromium.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=19765; h=from:subject; bh=GG9nmr532r4pl7tVh2IFzW2uuFJ/hvJpUQj5i4N5B0I=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBicdqB7/551GkKwZcI+OcZghRu66mEP7FMOhfFmE5a 67h/Z0iJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCYnHagQAKCRCJcvTf3G3AJtfAEA CqSqFekHoLTEwm5Qyt0UbimHFpi/b/6zyOUB2KND396l+syWQ1mJIbLGjTios1NH/eIxHjGEKJ1syg U7L/zPIs4XJhvSt5mtK7HHfsD2jlgvLX3UL7IgUlEzTG1onpa1dDWN1UtoN81ahy1fct7CMGoD/1ll 3ngnIysZAbkbazroo7sUYB/JX8DX8bsjNn97JBfq+F0NovBSkT6UKeW29aHUk5FoZhWo+bijLKKQBA JrEW47fYiaZ04M3TcLGaKkKLllkiajq0N/9TLMbmHrUZphVEZCSiD9eikb/Kpr28WXz4NX00Fu4CGe kq7UO4JP9HeF1pCMUg3iVoEHddmrfhdENHsLrAQzNrTdnkG+Jt7b+DxWscqIxexQR8D0GFXA1TavBy c52biYoOXViqwEmvm12u6MNQYxMVN2/v5fbzbwkcdy4DlhOuLC0Wu4AmEcPHG6wFuSX5NdbPBBeIzQ 911ljxSY+UGfg0USsjIzhH6oqejgpYUmqqLAV0WoW7O8aSmtqBCOORogwfI680pWARJhsTuTVbZ5G4 KsZcDi9opJFLcoYlb9wuFYeQrydBbShjiVXqT/tU0kK4PWWlEc85sOiKq7Bd8cuiixIgJW5Zlc+4n+ 1sgKfTbiJo/zVmyCeEmrKxLCEoinmDvnxEdOeXRWpeTslL+4jMSgSaBMHUCw== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org Add tests for the new flexible array structure helpers. These can be run with: make ARCH=um mrproper ./tools/testing/kunit/kunit.py config ./tools/testing/kunit/kunit.py run flex_array Cc: David Gow Cc: kunit-dev@googlegroups.com Signed-off-by: Kees Cook Reviewed-by: David Gow --- lib/Kconfig.debug | 12 +- lib/Makefile | 1 + lib/flex_array_kunit.c | 523 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 531 insertions(+), 5 deletions(-) create mode 100644 lib/flex_array_kunit.c diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 9077bb38bc93..8bae6b169c50 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -2551,11 +2551,6 @@ config OVERFLOW_KUNIT_TEST Builds unit tests for the check_*_overflow(), size_*(), allocation, and related 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 STACKINIT_KUNIT_TEST tristate "Test level of stack variable initialization" if !KUNIT_ALL_TESTS depends on KUNIT @@ -2567,6 +2562,13 @@ config STACKINIT_KUNIT_TEST CONFIG_GCC_PLUGIN_STRUCTLEAK, CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF, or CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL. +config FLEX_ARRAY_KUNIT_TEST + tristate "Test flex_*() family of helper functions at runtime" if !KUNIT_ALL_TESTS + depends on KUNIT + default KUNIT_ALL_TESTS + help + Builds unit tests for flexible array copy helper functions. + config TEST_UDELAY tristate "udelay test driver" help diff --git a/lib/Makefile b/lib/Makefile index 6b9ffc1bd1ee..9884318db330 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -366,6 +366,7 @@ obj-$(CONFIG_MEMCPY_KUNIT_TEST) += memcpy_kunit.o obj-$(CONFIG_OVERFLOW_KUNIT_TEST) += overflow_kunit.o CFLAGS_stackinit_kunit.o += $(call cc-disable-warning, switch-unreachable) obj-$(CONFIG_STACKINIT_KUNIT_TEST) += stackinit_kunit.o +obj-$(CONFIG_FLEX_ARRAY_KUNIT_TEST) += flex_array_kunit.o obj-$(CONFIG_GENERIC_LIB_DEVMEM_IS_ALLOWED) += devmem_is_allowed.o diff --git a/lib/flex_array_kunit.c b/lib/flex_array_kunit.c new file mode 100644 index 000000000000..48bee88945b4 --- /dev/null +++ b/lib/flex_array_kunit.c @@ -0,0 +1,523 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Test cases for flex_*() array manipulation helpers. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include + +#define COMPARE_STRUCTS(STRUCT_A, STRUCT_B) do { \ + STRUCT_A *ptr_A; \ + STRUCT_B *ptr_B; \ + int rc; \ + size_t size_A, size_B; \ + \ + /* matching types for flex array elements and count */ \ + KUNIT_EXPECT_EQ(test, sizeof(*ptr_A), sizeof(*ptr_B)); \ + KUNIT_EXPECT_TRUE(test, __same_type(*ptr_A->data, \ + *ptr_B->__flex_array_elements)); \ + KUNIT_EXPECT_TRUE(test, __same_type(ptr_A->datalen, \ + ptr_B->__flex_array_elements_count)); \ + KUNIT_EXPECT_EQ(test, sizeof(*ptr_A->data), \ + sizeof(*ptr_B->__flex_array_elements)); \ + KUNIT_EXPECT_EQ(test, offsetof(typeof(*ptr_A), data), \ + offsetof(typeof(*ptr_B), \ + __flex_array_elements)); \ + KUNIT_EXPECT_EQ(test, offsetof(typeof(*ptr_A), datalen), \ + offsetof(typeof(*ptr_B), \ + __flex_array_elements_count)); \ + \ + /* struct_size() vs __fas_bytes() */ \ + size_A = struct_size(ptr_A, data, 13); \ + rc = __fas_bytes(ptr_B, __flex_array_elements, \ + __flex_array_elements_count, 13, &size_B); \ + KUNIT_EXPECT_EQ(test, rc, 0); \ + KUNIT_EXPECT_EQ(test, size_A, size_B); \ + \ + /* flex_array_size() vs __fas_elements_bytes() */ \ + size_A = flex_array_size(ptr_A, data, 13); \ + rc = __fas_elements_bytes(ptr_B, __flex_array_elements, \ + __flex_array_elements_count, 13, &size_B); \ + KUNIT_EXPECT_EQ(test, rc, 0); \ + KUNIT_EXPECT_EQ(test, size_A, size_B); \ + \ + KUNIT_EXPECT_EQ(test, sizeof(*ptr_A) + size_A, \ + offsetof(typeof(*ptr_A), data) + \ + (sizeof(*ptr_A->data) * 13)); \ + KUNIT_EXPECT_EQ(test, sizeof(*ptr_B) + size_B, \ + offsetof(typeof(*ptr_B), \ + __flex_array_elements) + \ + (sizeof(*ptr_B->__flex_array_elements) * \ + 13)); \ +} while (0) + +struct normal { + size_t datalen; + u32 data[]; +}; + +struct decl_normal { + DECLARE_FLEX_ARRAY_ELEMENTS_COUNT(size_t, datalen); + DECLARE_FLEX_ARRAY_ELEMENTS(u32, data); +}; + +struct aligned { + unsigned short datalen; + char data[] __aligned(__alignof__(u64)); +}; + +struct decl_aligned { + DECLARE_FLEX_ARRAY_ELEMENTS_COUNT(unsigned short, datalen); + DECLARE_FLEX_ARRAY_ELEMENTS(char, data) __aligned(__alignof__(u64)); +}; + +static void struct_test(struct kunit *test) +{ + COMPARE_STRUCTS(struct normal, struct decl_normal); + COMPARE_STRUCTS(struct aligned, struct decl_aligned); +} + +/* Flexible array structure with internal padding. */ +struct flex_cpy_obj { + DECLARE_FLEX_ARRAY_ELEMENTS_COUNT(u8, count); + unsigned long empty; + char induce_padding; + /* padding ends up here */ + unsigned long after_padding; + DECLARE_FLEX_ARRAY_ELEMENTS(u32, flex); +}; + +/* Encapsulating flexible array structure. */ +struct flex_dup_obj { + unsigned long flags; + int junk; + struct flex_cpy_obj fas; +}; + +/* Flexible array struct of only bytes. */ +struct tiny_flex { + DECLARE_FLEX_ARRAY_ELEMENTS_COUNT(u8, count); + DECLARE_FLEX_ARRAY_ELEMENTS(u8, byte_array); +}; + +#define CHECK_COPY(ptr) do { \ + typeof(*(ptr)) *_cc_dst = (ptr); \ + KUNIT_EXPECT_EQ(test, _cc_dst->induce_padding, 0); \ + memcpy(&padding, &_cc_dst->induce_padding + sizeof(_cc_dst->induce_padding), \ + sizeof(padding)); \ + /* Padding should be zero too. */ \ + KUNIT_EXPECT_EQ(test, padding, 0); \ + KUNIT_EXPECT_EQ(test, src->count, _cc_dst->count); \ + KUNIT_EXPECT_EQ(test, _cc_dst->count, TEST_TARGET); \ + for (i = 0; i < _cc_dst->count - 1; i++) { \ + /* 'A' is 0x41, and here repeated in a u32. */ \ + KUNIT_EXPECT_EQ(test, _cc_dst->flex[i], 0x41414141); \ + } \ + /* Last item should be different. */ \ + KUNIT_EXPECT_EQ(test, _cc_dst->flex[_cc_dst->count - 1], 0x14141414); \ +} while (0) + +/* Test copying from one flexible array struct into another. */ +static void flex_cpy_test(struct kunit *test) +{ +#define TEST_BOUNDS 13 +#define TEST_TARGET 12 +#define TEST_SMALL 10 + struct flex_cpy_obj *src, *dst; + unsigned long padding; + int i, rc; + + /* Prepare open-coded source. */ + src = kzalloc(struct_size(src, flex, TEST_BOUNDS), GFP_KERNEL); + src->count = TEST_BOUNDS; + memset(src->flex, 'A', flex_array_size(src, flex, TEST_BOUNDS)); + src->flex[src->count - 2] = 0x14141414; + src->flex[src->count - 1] = 0x24242424; + + /* Prepare open-coded destination, alloc only. */ + dst = kzalloc(struct_size(src, flex, TEST_BOUNDS), GFP_KERNEL); + /* Pre-fill with 0xFE marker. */ + memset(dst, 0xFE, struct_size(src, flex, TEST_BOUNDS)); + /* Pretend we're 1 element smaller. */ + dst->count = TEST_TARGET; + + /* Pretend to match the target destination size. */ + src->count = TEST_TARGET; + + rc = flex_cpy(dst, src); + KUNIT_EXPECT_EQ(test, rc, 0); + CHECK_COPY(dst); + /* Item past last copied item is unchanged from initial memset. */ + KUNIT_EXPECT_EQ(test, dst->flex[dst->count], 0xFEFEFEFE); + + /* Now trip overflow, and verify we didn't clobber beyond end. */ + src->count = TEST_BOUNDS; + rc = flex_cpy(dst, src); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + /* Item past last copied item is unchanged from initial memset. */ + KUNIT_EXPECT_EQ(test, dst->flex[dst->count], 0xFEFEFEFE); + + /* Reset destination contents. */ + memset(dst, 0xFD, struct_size(src, flex, TEST_BOUNDS)); + dst->count = TEST_TARGET; + + /* Copy less than max. */ + src->count = TEST_SMALL; + rc = flex_cpy(dst, src); + KUNIT_EXPECT_EQ(test, rc, 0); + /* Verify count was adjusted. */ + KUNIT_EXPECT_EQ(test, dst->count, TEST_SMALL); + /* Verify element beyond src size was wiped. */ + KUNIT_EXPECT_EQ(test, dst->flex[TEST_SMALL], 0); + /* Verify element beyond original dst size was untouched. */ + KUNIT_EXPECT_EQ(test, dst->flex[TEST_TARGET], 0xFDFDFDFD); + + kfree(dst); + kfree(src); +#undef TEST_BOUNDS +#undef TEST_TARGET +#undef TEST_SMALL +} + +static void flex_dup_test(struct kunit *test) +{ +#define TEST_TARGET 12 + struct flex_cpy_obj *src, *dst = NULL, **null = NULL; + struct flex_dup_obj *encap = NULL; + unsigned long padding; + int i, rc; + + /* Prepare open-coded source. */ + src = kzalloc(struct_size(src, flex, TEST_TARGET), GFP_KERNEL); + src->count = TEST_TARGET; + memset(src->flex, 'A', flex_array_size(src, flex, TEST_TARGET)); + src->flex[src->count - 1] = 0x14141414; + + /* Reject NULL @alloc. */ + rc = flex_dup(null, src, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -EINVAL); + + /* Check good copy. */ + rc = flex_dup(&dst, src, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, 0); + KUNIT_ASSERT_TRUE(test, dst != NULL); + CHECK_COPY(dst); + + /* Reject non-NULL *@alloc. */ + rc = flex_dup(&dst, src, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -EINVAL); + + kfree(dst); + + /* Check good encap copy. */ + rc = __flex_dup(&encap, .fas, src, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, 0); + KUNIT_ASSERT_TRUE(test, dst != NULL); + CHECK_COPY(&encap->fas); + /* Check that items external to "fas" are zero. */ + KUNIT_EXPECT_EQ(test, encap->flags, 0); + KUNIT_EXPECT_EQ(test, encap->junk, 0); + kfree(encap); +#undef MAGIC_WORD +#undef TEST_TARGET +} + +static void mem_to_flex_test(struct kunit *test) +{ +#define TEST_TARGET 9 +#define TEST_MAX U8_MAX +#define MAGIC_WORD 0x03030303 + u8 magic_byte = MAGIC_WORD & 0xff; + struct flex_cpy_obj *dst; + size_t big = (size_t)INT_MAX + 1; + char small[] = "Hello"; + char *src; + u32 src_len; + int rc; + + /* Open coded allocations, 1 larger than actually used. */ + src_len = flex_array_size(dst, flex, TEST_MAX + 1); + src = kzalloc(src_len, GFP_KERNEL); + dst = kzalloc(struct_size(dst, flex, TEST_MAX + 1), GFP_KERNEL); + dst->count = TEST_TARGET; + + /* Fill source. */ + memset(src, magic_byte, src_len); + + /* Short copy is fine. */ + KUNIT_EXPECT_EQ(test, dst->flex[0], 0); + KUNIT_EXPECT_EQ(test, dst->flex[1], 0); + rc = mem_to_flex(dst, src, 1); + KUNIT_EXPECT_EQ(test, rc, 0); + KUNIT_EXPECT_EQ(test, dst->count, 1); + KUNIT_EXPECT_EQ(test, dst->after_padding, 0); + KUNIT_EXPECT_EQ(test, dst->flex[0], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, dst->flex[1], 0); + dst->count = TEST_TARGET; + + /* Reject negative elements count. */ + rc = mem_to_flex(dst, small, -1); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + /* Make sure dst is unchanged. */ + KUNIT_EXPECT_EQ(test, dst->flex[0], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, dst->flex[1], 0); + + /* Reject compile-time read overflow. */ + rc = mem_to_flex(dst, small, 20); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + /* Make sure dst is unchanged. */ + KUNIT_EXPECT_EQ(test, dst->flex[0], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, dst->flex[1], 0); + + /* Reject giant buffer source. */ + rc = mem_to_flex(dst, small, big); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + /* Make sure dst is unchanged. */ + KUNIT_EXPECT_EQ(test, dst->flex[0], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, dst->flex[1], 0); + + /* Copy beyond storage size is rejected. */ + dst->count = TEST_MAX; + KUNIT_EXPECT_EQ(test, dst->flex[TEST_MAX - 1], 0); + KUNIT_EXPECT_EQ(test, dst->flex[TEST_MAX], 0); + rc = mem_to_flex(dst, src, TEST_MAX + 1); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + /* Make sure dst is unchanged. */ + KUNIT_EXPECT_EQ(test, dst->flex[0], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, dst->flex[1], 0); + + kfree(dst); + kfree(src); +#undef MAGIC_WORD +#undef TEST_MAX +#undef TEST_TARGET +} + +static void mem_to_flex_dup_test(struct kunit *test) +{ +#define ELEMENTS_COUNT 259 +#define MAGIC_WORD 0xABABABAB + u8 magic_byte = MAGIC_WORD & 0xff; + struct flex_dup_obj *obj = NULL; + struct tiny_flex *tiny = NULL, **null = NULL; + size_t src_len, count, big = (size_t)INT_MAX + 1; + char small[] = "Hello"; + u8 *src; + int rc; + + src_len = struct_size(tiny, byte_array, ELEMENTS_COUNT); + src = kzalloc(src_len, GFP_KERNEL); + KUNIT_ASSERT_TRUE(test, src != NULL); + /* Fill with bytes. */ + memset(src, magic_byte, src_len); + KUNIT_EXPECT_EQ(test, src[0], magic_byte); + KUNIT_EXPECT_EQ(test, src[src_len / 2], magic_byte); + KUNIT_EXPECT_EQ(test, src[src_len - 1], magic_byte); + + /* Reject storage exceeding elements_count type. */ + count = ELEMENTS_COUNT; + rc = mem_to_flex_dup(&tiny, src, count, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + KUNIT_EXPECT_TRUE(test, tiny == NULL); + + /* Reject negative elements count. */ + rc = mem_to_flex_dup(&tiny, src, -1, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + KUNIT_EXPECT_TRUE(test, tiny == NULL); + + /* Reject compile-time read overflow. */ + rc = mem_to_flex_dup(&tiny, small, 20, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + KUNIT_EXPECT_TRUE(test, tiny == NULL); + + /* Reject giant buffer source. */ + rc = mem_to_flex_dup(&tiny, small, big, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + KUNIT_EXPECT_TRUE(test, tiny == NULL); + + /* Reject NULL @alloc. */ + rc = mem_to_flex_dup(null, src, count, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -EINVAL); + + /* Allow reasonable count.*/ + count = ELEMENTS_COUNT / 2; + rc = mem_to_flex_dup(&tiny, src, count, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, 0); + KUNIT_ASSERT_TRUE(test, tiny != NULL); + /* Spot check the copy happened. */ + KUNIT_EXPECT_EQ(test, tiny->count, count); + KUNIT_EXPECT_EQ(test, tiny->byte_array[0], magic_byte); + KUNIT_EXPECT_EQ(test, tiny->byte_array[count / 2], magic_byte); + KUNIT_EXPECT_EQ(test, tiny->byte_array[count - 1], magic_byte); + + /* Reject non-NULL *@alloc. */ + rc = mem_to_flex_dup(&tiny, src, count, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -EINVAL); + kfree(tiny); + + /* Works with encapsulation too. */ + count = ELEMENTS_COUNT / 10; + rc = __mem_to_flex_dup(&obj, .fas, src, count, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, 0); + KUNIT_ASSERT_TRUE(test, obj != NULL); + /* Spot check the copy happened. */ + KUNIT_EXPECT_EQ(test, obj->fas.count, count); + KUNIT_EXPECT_EQ(test, obj->fas.after_padding, 0); + KUNIT_EXPECT_EQ(test, obj->fas.flex[0], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, obj->fas.flex[count / 2], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, obj->fas.flex[count - 1], MAGIC_WORD); + /* Check members before flexible array struct are zero. */ + KUNIT_EXPECT_EQ(test, obj->flags, 0); + KUNIT_EXPECT_EQ(test, obj->junk, 0); + kfree(obj); +#undef MAGIC_WORD +#undef ELEMENTS_COUNT +} + +static void flex_to_mem_test(struct kunit *test) +{ +#define ELEMENTS_COUNT 200 +#define MAGIC_WORD 0xF1F2F3F4 + struct flex_cpy_obj *src; + typeof(*src->flex) *cast; + size_t src_len = struct_size(src, flex, ELEMENTS_COUNT); + size_t copy_len = flex_array_size(src, flex, ELEMENTS_COUNT); + int i, rc; + size_t bytes = 0; + u8 too_small; + u8 *dst; + + /* Create a filled flexible array struct. */ + src = kzalloc(src_len, GFP_KERNEL); + KUNIT_ASSERT_TRUE(test, src != NULL); + src->count = ELEMENTS_COUNT; + src->after_padding = 13; + for (i = 0; i < ELEMENTS_COUNT; i++) + src->flex[i] = MAGIC_WORD; + + /* Over-allocate space to do past-src_len checking. */ + dst = kzalloc(src_len * 2, GFP_KERNEL); + KUNIT_ASSERT_TRUE(test, dst != NULL); + cast = (void *)dst; + + /* Fail if dst is too small. */ + rc = flex_to_mem(dst, copy_len - 1, src, &bytes); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + /* Make sure nothing was copied. */ + KUNIT_EXPECT_EQ(test, bytes, 0); + KUNIT_EXPECT_EQ(test, cast[0], 0); + + /* Fail if type too small to hold size of copy. */ + KUNIT_EXPECT_GT(test, copy_len, type_max(typeof(too_small))); + rc = flex_to_mem(dst, copy_len, src, &too_small); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + /* Make sure nothing was copied. */ + KUNIT_EXPECT_EQ(test, bytes, 0); + KUNIT_EXPECT_EQ(test, cast[0], 0); + + /* Check good copy. */ + rc = flex_to_mem(dst, copy_len, src, &bytes); + KUNIT_EXPECT_EQ(test, rc, 0); + KUNIT_EXPECT_EQ(test, bytes, copy_len); + /* Spot check the copy */ + KUNIT_EXPECT_EQ(test, cast[0], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, cast[ELEMENTS_COUNT / 2], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, cast[ELEMENTS_COUNT - 1], MAGIC_WORD); + /* Make sure nothing was written after last element. */ + KUNIT_EXPECT_EQ(test, cast[ELEMENTS_COUNT], 0); + + kfree(dst); + kfree(src); +#undef MAGIC_WORD +#undef ELEMENTS_COUNT +} + +static void flex_to_mem_dup_test(struct kunit *test) +{ +#define ELEMENTS_COUNT 210 +#define MAGIC_WORD 0xF0F1F2F3 + struct flex_dup_obj *obj, **null = NULL; + struct flex_cpy_obj *src; + typeof(*src->flex) *cast; + size_t obj_len = struct_size(obj, fas.flex, ELEMENTS_COUNT); + size_t src_len = struct_size(src, flex, ELEMENTS_COUNT); + size_t copy_len = flex_array_size(src, flex, ELEMENTS_COUNT); + int i, rc; + size_t bytes = 0; + u8 too_small = 0; + u8 *dst = NULL; + + /* Create a filled flexible array struct. */ + obj = kzalloc(obj_len, GFP_KERNEL); + KUNIT_ASSERT_TRUE(test, obj != NULL); + obj->fas.count = ELEMENTS_COUNT; + obj->fas.after_padding = 13; + for (i = 0; i < ELEMENTS_COUNT; i++) + obj->fas.flex[i] = MAGIC_WORD; + src = &obj->fas; + + /* Fail if type too small to hold size of copy. */ + KUNIT_EXPECT_GT(test, src_len, type_max(typeof(too_small))); + rc = flex_to_mem_dup(&dst, &too_small, src, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -E2BIG); + KUNIT_EXPECT_TRUE(test, dst == NULL); + KUNIT_EXPECT_EQ(test, too_small, 0); + + /* Fail if @alloc_size is NULL. */ + KUNIT_EXPECT_TRUE(test, dst == NULL); + rc = flex_to_mem_dup(&dst, dst, src, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -EINVAL); + KUNIT_EXPECT_TRUE(test, dst == NULL); + + /* Fail if @alloc is NULL. */ + rc = flex_to_mem_dup(null, &bytes, src, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -EINVAL); + KUNIT_EXPECT_TRUE(test, dst == NULL); + KUNIT_EXPECT_EQ(test, bytes, 0); + + /* Check good copy. */ + rc = flex_to_mem_dup(&dst, &bytes, src, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, 0); + KUNIT_EXPECT_TRUE(test, dst != NULL); + KUNIT_EXPECT_EQ(test, bytes, copy_len); + cast = (void *)dst; + /* Spot check the copy */ + KUNIT_EXPECT_EQ(test, cast[0], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, cast[ELEMENTS_COUNT / 2], MAGIC_WORD); + KUNIT_EXPECT_EQ(test, cast[ELEMENTS_COUNT - 1], MAGIC_WORD); + + /* Fail if *@alloc is non-NULL. */ + bytes = 0; + rc = flex_to_mem_dup(&dst, &bytes, src, GFP_KERNEL); + KUNIT_EXPECT_EQ(test, rc, -EINVAL); + KUNIT_EXPECT_EQ(test, bytes, 0); + + kfree(dst); + kfree(obj); +#undef MAGIC_WORD +#undef ELEMENTS_COUNT +} + +static struct kunit_case flex_array_test_cases[] = { + KUNIT_CASE(struct_test), + KUNIT_CASE(flex_cpy_test), + KUNIT_CASE(flex_dup_test), + KUNIT_CASE(mem_to_flex_test), + KUNIT_CASE(mem_to_flex_dup_test), + KUNIT_CASE(flex_to_mem_test), + KUNIT_CASE(flex_to_mem_dup_test), + {} +}; + +static struct kunit_suite flex_array_test_suite = { + .name = "flex_array", + .test_cases = flex_array_test_cases, +}; + +kunit_test_suite(flex_array_test_suite); + +MODULE_LICENSE("GPL");