From patchwork Fri Apr 5 08:44:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dev Jain X-Patchwork-Id: 786617 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id CF61A15FD0A; Fri, 5 Apr 2024 08:50:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712307003; cv=none; b=jhtTyvblDRH/07NDbgaW3gHgTIu82+NWA+CTaQ5IPpNjtt3+JMqYUAOcKelTO02zwcqmhGrj7j84hy8DS68fCXtCi2kg2Dpyb9EDvqvr7GUTM6rYKJm8XG/w6YG9zy/a5gZRe74HOBaaKP+hQUoQKXSZsyXl/IVUYq7wupaeKh0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712307003; c=relaxed/simple; bh=p/8Fq+jpurELJ6V7Gi3YxX1mI3RCEZP5MKqChiEaFz0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=sfDqEbJMUnNfIkhtgYmouD1/Z5g79Iu+O2xK0fsB446Z6rJQuxY2aaykeIUq/8UmLHlMwj+wiwYuCmy//6GVFE8ilW1nNNqXWpJ3w8t+vaSAuJRy/YgWmJeBaDgwV2oOp2AulVlTzKwD5of14HDzDjo8ATQ6txLVXD9ocHFjW3A= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C73FFFEC; Fri, 5 Apr 2024 01:50:31 -0700 (PDT) Received: from e116581.blr.arm.com (e116581.arm.com [10.162.43.7]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id BF8443F64C; Fri, 5 Apr 2024 01:49:56 -0700 (PDT) From: Dev Jain To: shuah@kernel.org, linux-arm-kernel@lists.infradead.org Cc: linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Anshuman.Khandual@arm.com, suzuki.poulose@arm.com, ryan.roberts@arm.com, rob.herring@arm.com, Catalin.Marinas@arm.com, broonie@kernel.org, will@kernel.org, mark.rutland@arm.com, Dev Jain Subject: [PATCH 3/4] selftests/arm: Add elf test Date: Fri, 5 Apr 2024 14:14:09 +0530 Message-Id: <20240405084410.256788-4-dev.jain@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240405084410.256788-1-dev.jain@arm.com> References: <20240405084410.256788-1-dev.jain@arm.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This patch introduces an ELF parsing test; the 5th byte of the ELF header must be 0x01 for a 32-bit process. A basic sanity check is required to ensure that we are actually testing a 32-bit build. Signed-off-by: Dev Jain --- tools/testing/selftests/arm/elf/parse_elf.c | 75 +++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 tools/testing/selftests/arm/elf/parse_elf.c diff --git a/tools/testing/selftests/arm/elf/parse_elf.c b/tools/testing/selftests/arm/elf/parse_elf.c new file mode 100644 index 000000000000..decd65699858 --- /dev/null +++ b/tools/testing/selftests/arm/elf/parse_elf.c @@ -0,0 +1,75 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2024 ARM Limited + * + * Author : Dev Jain + * + * Parse elf header to confirm 32-bit process + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include + +#include + +/* The ELF file header. This appears at the start of every ELF file. */ + +struct elf_header { + unsigned char e_ident[16]; /* Magic number and other info */ + uint16_t e_type; /* Object file type */ + uint16_t e_machine; /* Architecture */ + uint32_t e_version; /* Object file version */ + uint64_t e_entry; /* Entry point virtual address */ + uint64_t e_phoff; /* Program header table file offset */ + uint64_t e_shoff; /* Section header table file offset */ + uint32_t e_flags; /* Processor-specific flags */ + uint16_t e_ehsize; /* ELF header size in bytes */ + uint16_t e_phentsize; /* Program header table entry size */ + uint16_t e_phnum; /* Program header table entry count */ + uint16_t e_shentsize; /* Section header table entry size */ + uint16_t e_shnum; /* Section header table entry count */ + uint16_t e_shstrndx; /* Section header string table index */ +}; + +static int read_elf_header(const char *elfFile) +{ + struct elf_header header; + FILE *file; + + file = fopen(elfFile, "r"); + if (file) { + + /* store header in struct */ + fread(&header, 1, sizeof(header), file); + fclose(file); + + /* sanity check: does it really follow ELF format */ + if (header.e_ident[0] == 0x7f && + header.e_ident[1] == 'E' && + header.e_ident[2] == 'L' && + header.e_ident[3] == 'F') { + if (header.e_ident[4] == 0x01) + return 0; + return 1; + } + ksft_exit_fail_msg("Cannot parse /proc/self/exe\n"); + } + ksft_exit_fail_msg("Cannot open /proc/self/exe\n"); + exit(EXIT_FAILURE); +} + +int main(int argc, char *argv[]) +{ + const char *file_name; + + ksft_print_header(); + ksft_set_plan(1); + + file_name = "/proc/self/exe"; + ksft_test_result(read_elf_header(file_name) == 0, "ELF is 32 bit\n"); + ksft_finished(); +}