scripts/sortextable.c - kernel/msm-4.19 - Gitiles

 /*
  * sortextable.c: Sort the kernel's exception table
  *
  * Copyright 2011 - 2012 Cavium, Inc.
  *
  * Based on code taken from recortmcount.c which is:
  *
  * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>.  All rights reserved.
  * Licensed under the GNU General Public License, version 2 (GPLv2).
  *
  * Restructured to fit Linux format, as well as other updates:
  *  Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
  */

 /*
  * Strategy: alter the vmlinux file in-place.
  */

 #include <sys/types.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <getopt.h>
 #include <elf.h>
 #include <fcntl.h>
 #include <setjmp.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>

 #include <tools/be_byteshift.h>
 #include <tools/le_byteshift.h>

 #ifndef EM_ARCOMPACT
 #define EM_ARCOMPACT	93
 #endif

 #ifndef EM_XTENSA
 #define EM_XTENSA	94
 #endif

 #ifndef EM_AARCH64
 #define EM_AARCH64	183
 #endif

 #ifndef EM_MICROBLAZE
 #define EM_MICROBLAZE	189
 #endif

 #ifndef EM_ARCV2
 #define EM_ARCV2	195
 #endif

 static int fd_map;	/* File descriptor for file being modified. */
 static int mmap_failed; /* Boolean flag. */
 static void *ehdr_curr; /* current ElfXX_Ehdr *  for resource cleanup */
 static struct stat sb;	/* Remember .st_size, etc. */
 static jmp_buf jmpenv;	/* setjmp/longjmp per-file error escape */

 /* setjmp() return values */
 enum {
 	SJ_SETJMP = 0,  /* hardwired first return */
 	SJ_FAIL,
 	SJ_SUCCEED
 };

 /* Per-file resource cleanup when multiple files. */
 static void
 cleanup(void)
 {
 	if (!mmap_failed)
 		munmap(ehdr_curr, sb.st_size);
 	close(fd_map);
 }

 static void __attribute__((noreturn))
 fail_file(void)
 {
 	cleanup();
 	longjmp(jmpenv, SJ_FAIL);
 }

 /*
  * Get the whole file as a programming convenience in order to avoid
  * malloc+lseek+read+free of many pieces.  If successful, then mmap
  * avoids copying unused pieces; else just read the whole file.
  * Open for both read and write.
  */
 static void *mmap_file(char const *fname)
 {
 	void *addr;

 	fd_map = open(fname, O_RDWR);
 	if (fd_map < 0 || fstat(fd_map, &sb) < 0) {
 		perror(fname);
 		fail_file();
 	}
 	if (!S_ISREG(sb.st_mode)) {
 		fprintf(stderr, "not a regular file: %s\n", fname);
 		fail_file();
 	}
 	addr = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_SHARED,
 		    fd_map, 0);
 	if (addr == MAP_FAILED) {
 		mmap_failed = 1;
 		fprintf(stderr, "Could not mmap file: %s\n", fname);
 		fail_file();
 	}
 	return addr;
 }

 static uint64_t r8be(const uint64_t *x)
 {
 	return get_unaligned_be64(x);
 }
 static uint32_t rbe(const uint32_t *x)
 {
 	return get_unaligned_be32(x);
 }
 static uint16_t r2be(const uint16_t *x)
 {
 	return get_unaligned_be16(x);
 }
 static uint64_t r8le(const uint64_t *x)
 {
 	return get_unaligned_le64(x);
 }
 static uint32_t rle(const uint32_t *x)
 {
 	return get_unaligned_le32(x);
 }
 static uint16_t r2le(const uint16_t *x)
 {
 	return get_unaligned_le16(x);
 }

 static void w8be(uint64_t val, uint64_t *x)
 {
 	put_unaligned_be64(val, x);
 }
 static void wbe(uint32_t val, uint32_t *x)
 {
 	put_unaligned_be32(val, x);
 }
 static void w2be(uint16_t val, uint16_t *x)
 {
 	put_unaligned_be16(val, x);
 }
 static void w8le(uint64_t val, uint64_t *x)
 {
 	put_unaligned_le64(val, x);
 }
 static void wle(uint32_t val, uint32_t *x)
 {
 	put_unaligned_le32(val, x);
 }
 static void w2le(uint16_t val, uint16_t *x)
 {
 	put_unaligned_le16(val, x);
 }

 static uint64_t (*r8)(const uint64_t *);
 static uint32_t (*r)(const uint32_t *);
 static uint16_t (*r2)(const uint16_t *);
 static void (*w8)(uint64_t, uint64_t *);
 static void (*w)(uint32_t, uint32_t *);
 static void (*w2)(uint16_t, uint16_t *);

 typedef void (*table_sort_t)(char *, int);

 /*
  * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
  * the way to -256..-1, to avoid conflicting with real section
  * indices.
  */
 #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1))

 static inline int is_shndx_special(unsigned int i)
 {
 	return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE;
 }

 /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
 static inline unsigned int get_secindex(unsigned int shndx,
 					unsigned int sym_offs,
 					const Elf32_Word *symtab_shndx_start)
 {
 	if (is_shndx_special(shndx))
 		return SPECIAL(shndx);
 	if (shndx != SHN_XINDEX)
 		return shndx;
 	return r(&symtab_shndx_start[sym_offs]);
 }

 /* 32 bit and 64 bit are very similar */
 #include "sortextable.h"
 #define SORTEXTABLE_64
 #include "sortextable.h"

 static int compare_relative_table(const void *a, const void *b)
 {
 	int32_t av = (int32_t)r(a);
 	int32_t bv = (int32_t)r(b);

 	if (av < bv)
 		return -1;
 	if (av > bv)
 		return 1;
 	return 0;
 }

 static void x86_sort_relative_table(char *extab_image, int image_size)
 {
 	int i;

 	i = 0;
 	while (i < image_size) {
 		uint32_t *loc = (uint32_t *)(extab_image + i);

 		w(r(loc) + i, loc);
 		w(r(loc + 1) + i + 4, loc + 1);
 		w(r(loc + 2) + i + 8, loc + 2);

 		i += sizeof(uint32_t) * 3;
 	}

 	qsort(extab_image, image_size / 12, 12, compare_relative_table);

 	i = 0;
 	while (i < image_size) {
 		uint32_t *loc = (uint32_t *)(extab_image + i);

 		w(r(loc) - i, loc);
 		w(r(loc + 1) - (i + 4), loc + 1);
 		w(r(loc + 2) - (i + 8), loc + 2);

 		i += sizeof(uint32_t) * 3;
 	}
 }

 static void sort_relative_table(char *extab_image, int image_size)
 {
 	int i;

 	/*
 	 * Do the same thing the runtime sort does, first normalize to
 	 * being relative to the start of the section.
 	 */
 	i = 0;
 	while (i < image_size) {
 		uint32_t *loc = (uint32_t *)(extab_image + i);
 		w(r(loc) + i, loc);
 		i += 4;
 	}

 	qsort(extab_image, image_size / 8, 8, compare_relative_table);

 	/* Now denormalize. */
 	i = 0;
 	while (i < image_size) {
 		uint32_t *loc = (uint32_t *)(extab_image + i);
 		w(r(loc) - i, loc);
 		i += 4;
 	}
 }

 static void
 do_file(char const *const fname)
 {
 	table_sort_t custom_sort;
 	Elf32_Ehdr *ehdr = mmap_file(fname);

 	ehdr_curr = ehdr;
 	switch (ehdr->e_ident[EI_DATA]) {
 	default:
 		fprintf(stderr, "unrecognized ELF data encoding %d: %s\n",
 			ehdr->e_ident[EI_DATA], fname);
 		fail_file();
 		break;
 	case ELFDATA2LSB:
 		r = rle;
 		r2 = r2le;
 		r8 = r8le;
 		w = wle;
 		w2 = w2le;
 		w8 = w8le;
 		break;
 	case ELFDATA2MSB:
 		r = rbe;
 		r2 = r2be;
 		r8 = r8be;
 		w = wbe;
 		w2 = w2be;
 		w8 = w8be;
 		break;
 	}  /* end switch */
 	if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0
 	||  (r2(&ehdr->e_type) != ET_EXEC && r2(&ehdr->e_type) != ET_DYN)
 	||  ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
 		fprintf(stderr, "unrecognized ET_EXEC/ET_DYN file %s\n", fname);
 		fail_file();
 	}

 	custom_sort = NULL;
 	switch (r2(&ehdr->e_machine)) {
 	default:
 		fprintf(stderr, "unrecognized e_machine %d %s\n",
 			r2(&ehdr->e_machine), fname);
 		fail_file();
 		break;
 	case EM_386:
 	case EM_X86_64:
 		custom_sort = x86_sort_relative_table;
 		break;

 	case EM_S390:
 	case EM_AARCH64:
 		custom_sort = sort_relative_table;
 		break;
 	case EM_ARCOMPACT:
 	case EM_ARCV2:
 	case EM_ARM:
 	case EM_MICROBLAZE:
 	case EM_MIPS:
 	case EM_XTENSA:
 		break;
 	}  /* end switch */

 	switch (ehdr->e_ident[EI_CLASS]) {
 	default:
 		fprintf(stderr, "unrecognized ELF class %d %s\n",
 			ehdr->e_ident[EI_CLASS], fname);
 		fail_file();
 		break;
 	case ELFCLASS32:
 		if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr)
 		||  r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) {
 			fprintf(stderr,
 				"unrecognized ET_EXEC/ET_DYN file: %s\n", fname);
 			fail_file();
 		}
 		do32(ehdr, fname, custom_sort);
 		break;
 	case ELFCLASS64: {
 		Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr;
 		if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr)
 		||  r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) {
 			fprintf(stderr,
 				"unrecognized ET_EXEC/ET_DYN file: %s\n", fname);
 			fail_file();
 		}
 		do64(ghdr, fname, custom_sort);
 		break;
 	}
 	}  /* end switch */

 	cleanup();
 }

 int
 main(int argc, char *argv[])
 {
 	int n_error = 0;  /* gcc-4.3.0 false positive complaint */
 	int i;

 	if (argc < 2) {
 		fprintf(stderr, "usage: sortextable vmlinux...\n");
 		return 0;
 	}

 	/* Process each file in turn, allowing deep failure. */
 	for (i = 1; i < argc; i++) {
 		char *file = argv[i];
 		int const sjval = setjmp(jmpenv);

 		switch (sjval) {
 		default:
 			fprintf(stderr, "internal error: %s\n", file);
 			exit(1);
 			break;
 		case SJ_SETJMP:    /* normal sequence */
 			/* Avoid problems if early cleanup() */
 			fd_map = -1;
 			ehdr_curr = NULL;
 			mmap_failed = 1;
 			do_file(file);
 			break;
 		case SJ_FAIL:    /* error in do_file or below */
 			++n_error;
 			break;
 		case SJ_SUCCEED:    /* premature success */
 			/* do nothing */
 			break;
 		}  /* end switch */
 	}
 	return !!n_error;
 }
	/*
	* sortextable.c: Sort the kernel's exception table
	*
	* Copyright 2011 - 2012 Cavium, Inc.
	*
	* Based on code taken from recortmcount.c which is:
	*
	* Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved.
	* Licensed under the GNU General Public License, version 2 (GPLv2).
	*
	* Restructured to fit Linux format, as well as other updates:
	* Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
	*/

	/*
	* Strategy: alter the vmlinux file in-place.
	*/

	#include <sys/types.h>
	#include <sys/mman.h>
	#include <sys/stat.h>
	#include <getopt.h>
	#include <elf.h>
	#include <fcntl.h>
	#include <setjmp.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <unistd.h>

	#include <tools/be_byteshift.h>
	#include <tools/le_byteshift.h>

	#ifndef EM_ARCOMPACT
	#define EM_ARCOMPACT 93
	#endif

	#ifndef EM_XTENSA
	#define EM_XTENSA 94
	#endif

	#ifndef EM_AARCH64
	#define EM_AARCH64 183
	#endif

	#ifndef EM_MICROBLAZE
	#define EM_MICROBLAZE 189
	#endif

	#ifndef EM_ARCV2
	#define EM_ARCV2 195
	#endif

	static int fd_map; /* File descriptor for file being modified. */
	static int mmap_failed; /* Boolean flag. */
	static void ehdr_curr; / current ElfXX_Ehdr * for resource cleanup */
	static struct stat sb; /* Remember .st_size, etc. */
	static jmp_buf jmpenv; /* setjmp/longjmp per-file error escape */

	/* setjmp() return values */
	enum {
	SJ_SETJMP = 0, /* hardwired first return */
	SJ_FAIL,
	SJ_SUCCEED
	};

	/* Per-file resource cleanup when multiple files. */
	static void
	cleanup(void)
	{
	if (!mmap_failed)
	munmap(ehdr_curr, sb.st_size);
	close(fd_map);
	}

	static void __attribute__((noreturn))
	fail_file(void)
	{
	cleanup();
	longjmp(jmpenv, SJ_FAIL);
	}

	/*
	* Get the whole file as a programming convenience in order to avoid
	* malloc+lseek+read+free of many pieces. If successful, then mmap
	* avoids copying unused pieces; else just read the whole file.
	* Open for both read and write.
	*/
	static void mmap_file(char const fname)
	{
	void *addr;

	fd_map = open(fname, O_RDWR);
	if (fd_map < 0 \|\| fstat(fd_map, &sb) < 0) {
	perror(fname);
	fail_file();
	}
	if (!S_ISREG(sb.st_mode)) {
	fprintf(stderr, "not a regular file: %s\n", fname);
	fail_file();
	}
	addr = mmap(0, sb.st_size, PROT_READ\|PROT_WRITE, MAP_SHARED,
	fd_map, 0);
	if (addr == MAP_FAILED) {
	mmap_failed = 1;
	fprintf(stderr, "Could not mmap file: %s\n", fname);
	fail_file();
	}
	return addr;
	}

	static uint64_t r8be(const uint64_t *x)
	{
	return get_unaligned_be64(x);
	}
	static uint32_t rbe(const uint32_t *x)
	{
	return get_unaligned_be32(x);
	}
	static uint16_t r2be(const uint16_t *x)
	{
	return get_unaligned_be16(x);
	}
	static uint64_t r8le(const uint64_t *x)
	{
	return get_unaligned_le64(x);
	}
	static uint32_t rle(const uint32_t *x)
	{
	return get_unaligned_le32(x);
	}
	static uint16_t r2le(const uint16_t *x)
	{
	return get_unaligned_le16(x);
	}

	static void w8be(uint64_t val, uint64_t *x)
	{
	put_unaligned_be64(val, x);
	}
	static void wbe(uint32_t val, uint32_t *x)
	{
	put_unaligned_be32(val, x);
	}
	static void w2be(uint16_t val, uint16_t *x)
	{
	put_unaligned_be16(val, x);
	}
	static void w8le(uint64_t val, uint64_t *x)
	{
	put_unaligned_le64(val, x);
	}
	static void wle(uint32_t val, uint32_t *x)
	{
	put_unaligned_le32(val, x);
	}
	static void w2le(uint16_t val, uint16_t *x)
	{
	put_unaligned_le16(val, x);
	}

	static uint64_t (r8)(const uint64_t );
	static uint32_t (r)(const uint32_t );
	static uint16_t (r2)(const uint16_t );
	static void (w8)(uint64_t, uint64_t );
	static void (w)(uint32_t, uint32_t );
	static void (w2)(uint16_t, uint16_t );

	typedef void (table_sort_t)(char , int);

	/*
	* Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
	* the way to -256..-1, to avoid conflicting with real section
	* indices.
	*/
	#define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1))

	static inline int is_shndx_special(unsigned int i)
	{
	return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE;
	}

	/* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
	static inline unsigned int get_secindex(unsigned int shndx,
	unsigned int sym_offs,
	const Elf32_Word *symtab_shndx_start)
	{
	if (is_shndx_special(shndx))
	return SPECIAL(shndx);
	if (shndx != SHN_XINDEX)
	return shndx;
	return r(&symtab_shndx_start[sym_offs]);
	}

	/* 32 bit and 64 bit are very similar */
	#include "sortextable.h"
	#define SORTEXTABLE_64
	#include "sortextable.h"

	static int compare_relative_table(const void a, const void b)
	{
	int32_t av = (int32_t)r(a);
	int32_t bv = (int32_t)r(b);

	if (av < bv)
	return -1;
	if (av > bv)
	return 1;
	return 0;
	}

	static void x86_sort_relative_table(char *extab_image, int image_size)
	{
	int i;

	i = 0;
	while (i < image_size) {
	uint32_t loc = (uint32_t )(extab_image + i);

	w(r(loc) + i, loc);
	w(r(loc + 1) + i + 4, loc + 1);
	w(r(loc + 2) + i + 8, loc + 2);

	i += sizeof(uint32_t) * 3;
	}

	qsort(extab_image, image_size / 12, 12, compare_relative_table);

	i = 0;
	while (i < image_size) {
	uint32_t loc = (uint32_t )(extab_image + i);

	w(r(loc) - i, loc);
	w(r(loc + 1) - (i + 4), loc + 1);
	w(r(loc + 2) - (i + 8), loc + 2);

	i += sizeof(uint32_t) * 3;
	}
	}

	static void sort_relative_table(char *extab_image, int image_size)
	{
	int i;

	/*
	* Do the same thing the runtime sort does, first normalize to
	* being relative to the start of the section.
	*/
	i = 0;
	while (i < image_size) {
	uint32_t loc = (uint32_t )(extab_image + i);
	w(r(loc) + i, loc);
	i += 4;
	}

	qsort(extab_image, image_size / 8, 8, compare_relative_table);

	/* Now denormalize. */
	i = 0;
	while (i < image_size) {
	uint32_t loc = (uint32_t )(extab_image + i);
	w(r(loc) - i, loc);
	i += 4;
	}
	}

	static void
	do_file(char const *const fname)
	{
	table_sort_t custom_sort;
	Elf32_Ehdr *ehdr = mmap_file(fname);

	ehdr_curr = ehdr;
	switch (ehdr->e_ident[EI_DATA]) {
	default:
	fprintf(stderr, "unrecognized ELF data encoding %d: %s\n",
	ehdr->e_ident[EI_DATA], fname);
	fail_file();
	break;
	case ELFDATA2LSB:
	r = rle;
	r2 = r2le;
	r8 = r8le;
	w = wle;
	w2 = w2le;
	w8 = w8le;
	break;
	case ELFDATA2MSB:
	r = rbe;
	r2 = r2be;
	r8 = r8be;
	w = wbe;
	w2 = w2be;
	w8 = w8be;
	break;
	} /* end switch */
	if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0
	\|\| (r2(&ehdr->e_type) != ET_EXEC && r2(&ehdr->e_type) != ET_DYN)
	\|\| ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
	fprintf(stderr, "unrecognized ET_EXEC/ET_DYN file %s\n", fname);
	fail_file();
	}

	custom_sort = NULL;
	switch (r2(&ehdr->e_machine)) {
	default:
	fprintf(stderr, "unrecognized e_machine %d %s\n",
	r2(&ehdr->e_machine), fname);
	fail_file();
	break;
	case EM_386:
	case EM_X86_64:
	custom_sort = x86_sort_relative_table;
	break;

	case EM_S390:
	case EM_AARCH64:
	custom_sort = sort_relative_table;
	break;
	case EM_ARCOMPACT:
	case EM_ARCV2:
	case EM_ARM:
	case EM_MICROBLAZE:
	case EM_MIPS:
	case EM_XTENSA:
	break;
	} /* end switch */

	switch (ehdr->e_ident[EI_CLASS]) {
	default:
	fprintf(stderr, "unrecognized ELF class %d %s\n",
	ehdr->e_ident[EI_CLASS], fname);
	fail_file();
	break;
	case ELFCLASS32:
	if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr)
	\|\| r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) {
	fprintf(stderr,
	"unrecognized ET_EXEC/ET_DYN file: %s\n", fname);
	fail_file();
	}
	do32(ehdr, fname, custom_sort);
	break;
	case ELFCLASS64: {
	Elf64_Ehdr const ghdr = (Elf64_Ehdr )ehdr;
	if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr)
	\|\| r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) {
	fprintf(stderr,
	"unrecognized ET_EXEC/ET_DYN file: %s\n", fname);
	fail_file();
	}
	do64(ghdr, fname, custom_sort);
	break;
	}
	} /* end switch */

	cleanup();
	}

	int
	main(int argc, char *argv[])
	{
	int n_error = 0; /* gcc-4.3.0 false positive complaint */
	int i;

	if (argc < 2) {
	fprintf(stderr, "usage: sortextable vmlinux...\n");
	return 0;
	}

	/* Process each file in turn, allowing deep failure. */
	for (i = 1; i < argc; i++) {
	char *file = argv[i];
	int const sjval = setjmp(jmpenv);

	switch (sjval) {
	default:
	fprintf(stderr, "internal error: %s\n", file);
	exit(1);
	break;
	case SJ_SETJMP: /* normal sequence */
	/* Avoid problems if early cleanup() */
	fd_map = -1;
	ehdr_curr = NULL;
	mmap_failed = 1;
	do_file(file);
	break;
	case SJ_FAIL: /* error in do_file or below */
	++n_error;
	break;
	case SJ_SUCCEED: /* premature success */
	/* do nothing */
	break;
	} /* end switch */
	}
	return !!n_error;
	}