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[PATCH 3/4] selftests/arm: Add elf test

Dev Jain posted 4 patches 1 year, 10 months ago
There is a newer version of this series
[PATCH 3/4] selftests/arm: Add elf test
Posted by Dev Jain 1 year, 10 months ago 
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 <dev.jain@arm.com>
---
 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 <dev.jain@arm.com>
+ *
+ * Parse elf header to confirm 32-bit process
+ */
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <elf.h>
+#include <stdint.h>
+
+#include <kselftest.h>
+
+/* 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();
+}
-- 
2.39.2
Re: [PATCH 3/4] selftests/arm: Add elf test
Posted by Muhammad Usama Anjum 1 year, 10 months ago 
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 <dev.jain@arm.com>
> ---
>  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 <dev.jain@arm.com>
> + *
> + * Parse elf header to confirm 32-bit process
> + */
> +
> +#define _GNU_SOURCE
> +#include <stdio.h>
> +#include <unistd.h>
> +#include <stdlib.h>
> +#include <elf.h>
> +#include <stdint.h>
> +
> +#include <kselftest.h>
> +
> +/* 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().

> +}
> +
> +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();
> +}

-- 
BR,
Muhammad Usama Anjum
Re: [PATCH 3/4] selftests/arm: Add elf test
Posted by Dev Jain 1 year, 10 months ago 
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 <dev.jain@arm.com>
>> ---
>>   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 <dev.jain@arm.com>
>> + *
>> + * Parse elf header to confirm 32-bit process
>> + */
>> +
>> +#define _GNU_SOURCE
>> +#include <stdio.h>
>> +#include <unistd.h>
>> +#include <stdlib.h>
>> +#include <elf.h>
>> +#include <stdint.h>
>> +
>> +#include <kselftest.h>
>> +
>> +/* 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();
>> +}

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