From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E0474C127; Wed, 10 Apr 2024 04:11:08 +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=1712722271; cv=none; b=aE4qk7+IZLhjoP1bnPSoPTtg/TAte+6pdaKx3L9Nz2cxMvU954B0U868PSflQZoO/uLGRZ4/0FXFqyfYMq675/qzRuK4D3zJaOR6Jb5wAYQ8lCknpXDjQKt8K2behYFA0ctM5FkIxsfVdOtSOED6yUBCMoMl6rq935ebXCHHR1E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712722271; c=relaxed/simple; bh=0m0M4CKHOltghRB0qj2gqbMWbmEB2TWk1Qvso1asGZ0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=SRl/bGz5y95UKd5YeSmEDkMVzke9o1G+N/inexXY25SHNirN3gqEPqHUCdY5YGd3pU3w/0rPivgF6ucXYEh2KsSy3u6yhIPRTX8LHT5jSCIngSoRwknS0g8cu/5ifSQgA25FFzNDuJnOj6C5aDeqyM6AMtLL9FUfd+Mac8ZGYUY= 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 AD018139F; Tue, 9 Apr 2024 21:11:37 -0700 (PDT) Received: from [10.162.40.22] (e116581.arm.com [10.162.40.22]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A61BC3F6C4; Tue, 9 Apr 2024 21:11:03 -0700 (PDT) Message-ID: <15a24a03-6e83-4a25-803a-5c5efcd393fd@arm.com> Date: Wed, 10 Apr 2024 09:41:00 +0530 Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 3/4] selftests/arm: Add elf test To: Muhammad Usama Anjum , 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 References: <20240405084410.256788-1-dev.jain@arm.com> <20240405084410.256788-4-dev.jain@arm.com> <1913ab65-b3d2-40b9-9f81-c9ee9c769d91@collabora.com> Content-Language: en-US From: Dev Jain In-Reply-To: <1913ab65-b3d2-40b9-9f81-c9ee9c769d91@collabora.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 4/7/24 03:00, Muhammad Usama Anjum wrote: > On 4/5/24 1:44 PM, Dev Jain wrote: >> 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); > Instead of failing and exiting multiple times here, use ksft_print_msg, > return error or -1 from here and fail the test case in ksft_test_result(). Thanks for the suggestion. > >> +} >> + >> +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(); >> +}