imgact_linux.c revision 20852
1/*- 2 * Copyright (c) 1994-1996 S�ren Schmidt 3 * All rights reserved. 4 * 5 * Based heavily on /sys/kern/imgact_aout.c which is: 6 * Copyright (c) 1993, David Greenman 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer 13 * in this position and unchanged. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. The name of the author may not be used to endorse or promote products 18 * derived from this software withough specific prior written permission 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 * 31 * $Id: imgact_linux.c,v 1.17 1996/12/22 23:17:00 joerg Exp $ 32 */ 33 34#ifndef LKM 35#include "opt_rlimit.h" 36#endif 37 38#include <sys/param.h> 39#include <sys/systm.h> 40#include <sys/resourcevar.h> 41#include <sys/exec.h> 42#include <sys/mman.h> 43#include <sys/imgact.h> 44#include <sys/imgact_aout.h> 45#include <sys/kernel.h> 46#include <sys/proc.h> 47#include <sys/sysent.h> 48#include <sys/vnode.h> 49 50#include <vm/vm.h> 51#include <vm/vm_kern.h> 52#include <vm/vm_param.h> 53#include <vm/pmap.h> 54#include <vm/lock.h> 55#include <vm/vm_map.h> 56#include <vm/vm_prot.h> 57#include <vm/vm_extern.h> 58 59#include <i386/linux/linux.h> 60#include <i386/linux/linux_proto.h> 61 62extern int exec_linux_imgact __P((struct image_params *iparams)); 63 64int 65exec_linux_imgact(imgp) 66 struct image_params *imgp; 67{ 68 const struct exec *a_out = (const struct exec *) imgp->image_header; 69 struct vmspace *vmspace = imgp->proc->p_vmspace; 70 vm_offset_t vmaddr; 71 unsigned long virtual_offset, file_offset; 72 vm_offset_t buffer; 73 unsigned long bss_size; 74 int error; 75 76 if (((a_out->a_magic >> 16) & 0xff) != 0x64) 77 return -1; 78 79 /* 80 * Set file/virtual offset based on a.out variant. 81 */ 82 switch ((int)(a_out->a_magic & 0xffff)) { 83 case 0413: 84 virtual_offset = 0; 85 file_offset = 1024; 86 break; 87 case 0314: 88 virtual_offset = 4096; 89 file_offset = 0; 90 break; 91 default: 92 return (-1); 93 } 94 bss_size = round_page(a_out->a_bss); 95#ifdef DEBUG 96 printf("imgact: text: %08x, data: %08x, bss: %08x\n", a_out->a_text, a_out->a_data, bss_size); 97#endif 98 99 /* 100 * Check various fields in header for validity/bounds. 101 */ 102 if (a_out->a_entry < virtual_offset || 103 a_out->a_entry >= virtual_offset + a_out->a_text || 104 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK) 105 return (-1); 106 107 /* text + data can't exceed file size */ 108 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 109 return (EFAULT); 110 /* 111 * text/data/bss must not exceed limits 112 */ 113 if (a_out->a_text > MAXTSIZ || a_out->a_data + bss_size > MAXDSIZ || 114 a_out->a_data+bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 115 return (ENOMEM); 116 117 /* copy in arguments and/or environment from old process */ 118 error = exec_extract_strings(imgp); 119 if (error) 120 return (error); 121 122 /* 123 * Destroy old process VM and create a new one (with a new stack) 124 */ 125 exec_new_vmspace(imgp); 126 127 /* 128 * Check if file_offset page aligned,. 129 * Currently we cannot handle misalinged file offsets, 130 * and so we read in the entire image (what a waste). 131 */ 132 if (file_offset & PAGE_MASK) { 133#ifdef DEBUG 134 printf("imgact: Non page aligned binary %d\n", file_offset); 135#endif 136 /* 137 * Map text+data+bss read/write/execute 138 */ 139 vmaddr = virtual_offset; 140 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 141 a_out->a_text + a_out->a_data + bss_size, FALSE, 142 VM_PROT_ALL, VM_PROT_ALL, 0); 143 if (error) 144 return error; 145 146 error = vm_mmap(kernel_map, &buffer, 147 round_page(a_out->a_text + a_out->a_data + file_offset), 148 VM_PROT_READ, VM_PROT_READ, 0, 149 (caddr_t) imgp->vp, trunc_page(file_offset)); 150 if (error) 151 return error; 152 153 error = copyout((caddr_t)(buffer + file_offset), (caddr_t)vmaddr, 154 a_out->a_text + a_out->a_data); 155 156 vm_map_remove(kernel_map, buffer, 157 buffer + round_page(a_out->a_text + a_out->a_data + file_offset)); 158 159 if (error) 160 return error; 161 162 /* 163 * remove write enable on the 'text' part 164 */ 165 error = vm_map_protect(&vmspace->vm_map, 166 vmaddr, 167 vmaddr + a_out->a_text, 168 VM_PROT_EXECUTE|VM_PROT_READ, 169 TRUE); 170 if (error) 171 return error; 172 } 173 else { 174#ifdef DEBUG 175 printf("imgact: Page aligned binary %d\n", file_offset); 176#endif 177 /* 178 * Map text+data read/execute 179 */ 180 vmaddr = virtual_offset; 181 error = vm_mmap(&vmspace->vm_map, &vmaddr, 182 a_out->a_text + a_out->a_data, 183 VM_PROT_READ | VM_PROT_EXECUTE, 184 VM_PROT_ALL, 185 MAP_PRIVATE | MAP_FIXED, 186 (caddr_t)imgp->vp, file_offset); 187 if (error) 188 return (error); 189 190#ifdef DEBUG 191 printf("imgact: startaddr=%08x, length=%08x\n", vmaddr, a_out->a_text + a_out->a_data); 192#endif 193 /* 194 * allow read/write of data 195 */ 196 error = vm_map_protect(&vmspace->vm_map, 197 vmaddr + a_out->a_text, 198 vmaddr + a_out->a_text + a_out->a_data, 199 VM_PROT_ALL, 200 FALSE); 201 if (error) 202 return (error); 203 204 /* 205 * Allocate anon demand-zeroed area for uninitialized data 206 */ 207 if (bss_size != 0) { 208 vmaddr = virtual_offset + a_out->a_text + a_out->a_data; 209 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 210 bss_size, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0); 211 if (error) 212 return (error); 213#ifdef DEBUG 214 printf("imgact: bssaddr=%08x, length=%08x\n", vmaddr, bss_size); 215#endif 216 217 } 218 /* Indicate that this file should not be modified */ 219 imgp->vp->v_flag |= VTEXT; 220 } 221 /* Fill in process VM information */ 222 vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT; 223 vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT; 224 vmspace->vm_taddr = (caddr_t)virtual_offset; 225 vmspace->vm_daddr = (caddr_t)virtual_offset + a_out->a_text; 226 227 /* Fill in image_params */ 228 imgp->interpreted = 0; 229 imgp->entry_addr = a_out->a_entry; 230 231 imgp->proc->p_sysent = &linux_sysvec; 232 return (0); 233} 234 235/* 236 * Tell kern_execve.c about it, with a little help from the linker. 237 * Since `const' objects end up in the text segment, TEXT_SET is the 238 * correct directive to use. 239 */ 240const struct execsw linux_execsw = { exec_linux_imgact, "linux a.out" }; 241TEXT_SET(execsw_set, linux_execsw); 242 243