cregit-Linux how code gets into the kernel

Release 4.14 arch/mn10300/kernel/module.c

/* MN10300 Kernel module helper routines
 *
 * Copyright (C) 2007, 2008, 2009 Red Hat, Inc. All Rights Reserved.
 * Written by Mark Salter (msalter@redhat.com)
 * - Derived from arch/i386/kernel/module.c
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public Licence as published by
 * the Free Software Foundation; either version 2 of the Licence, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public Licence for more details.
 *
 * You should have received a copy of the GNU General Public Licence
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <linux/moduleloader.h>
#include <linux/elf.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/bug.h>

#if 0
#define DEBUGP printk
#else

#define DEBUGP(fmt, ...)
#endif


static void reloc_put16(uint8_t *p, uint32_t val) { p[0] = val & 0xff; p[1] = (val >> 8) & 0xff; }

Contributors

PersonTokensPropCommitsCommitProp
David Howells35100.00%1100.00%
Total35100.00%1100.00%


static void reloc_put24(uint8_t *p, uint32_t val) { reloc_put16(p, val); p[2] = (val >> 16) & 0xff; }

Contributors

PersonTokensPropCommitsCommitProp
David Howells33100.00%1100.00%
Total33100.00%1100.00%


static void reloc_put32(uint8_t *p, uint32_t val) { reloc_put16(p, val); reloc_put16(p+2, val >> 16); }

Contributors

PersonTokensPropCommitsCommitProp
David Howells31100.00%1100.00%
Total31100.00%1100.00%

/* * apply a RELA relocation */
int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex, unsigned int relsec, struct module *me) { unsigned int i, sym_diff_seen = 0; Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; Elf32_Sym *sym; Elf32_Addr relocation, sym_diff_val = 0; uint8_t *location; uint32_t value; DEBUGP("Applying relocate section %u to %u\n", relsec, sechdrs[relsec].sh_info); for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { /* this is where to make the change */ location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr + rel[i].r_offset; /* this is the symbol the relocation is referring to (note that * all undefined symbols have been resolved by the caller) */ sym = (Elf32_Sym *)sechdrs[symindex].sh_addr + ELF32_R_SYM(rel[i].r_info); /* this is the adjustment to be made */ relocation = sym->st_value + rel[i].r_addend; if (sym_diff_seen) { switch (ELF32_R_TYPE(rel[i].r_info)) { case R_MN10300_32: case R_MN10300_24: case R_MN10300_16: case R_MN10300_8: relocation -= sym_diff_val; sym_diff_seen = 0; break; default: printk(KERN_ERR "module %s: Unexpected SYM_DIFF relocation: %u\n", me->name, ELF32_R_TYPE(rel[i].r_info)); return -ENOEXEC; } } switch (ELF32_R_TYPE(rel[i].r_info)) { /* for the first four relocation types, we simply * store the adjustment at the location given */ case R_MN10300_32: reloc_put32(location, relocation); break; case R_MN10300_24: reloc_put24(location, relocation); break; case R_MN10300_16: reloc_put16(location, relocation); break; case R_MN10300_8: *location = relocation; break; /* for the next three relocation types, we write the * adjustment with the address subtracted over the * value at the location given */ case R_MN10300_PCREL32: value = relocation - (uint32_t) location; reloc_put32(location, value); break; case R_MN10300_PCREL16: value = relocation - (uint32_t) location; reloc_put16(location, value); break; case R_MN10300_PCREL8: *location = relocation - (uint32_t) location; break; case R_MN10300_SYM_DIFF: /* This is used to adjust the next reloc as required * by relaxation. */ sym_diff_seen = 1; sym_diff_val = sym->st_value; break; case R_MN10300_ALIGN: /* Just ignore the ALIGN relocs. * Only interesting if kernel performed relaxation. */ continue; default: printk(KERN_ERR "module %s: Unknown relocation: %u\n", me->name, ELF32_R_TYPE(rel[i].r_info)); return -ENOEXEC; } } if (sym_diff_seen) { printk(KERN_ERR "module %s: Nothing follows SYM_DIFF relocation: %u\n", me->name, ELF32_R_TYPE(rel[i].r_info)); return -ENOEXEC; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
David Howells29969.86%133.33%
Mark Salter12930.14%266.67%
Total428100.00%3100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
David Howells43676.63%125.00%
Mark Salter13022.85%250.00%
Paul Mundt30.53%125.00%
Total569100.00%4100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.