imgact_linux.c revision 12689
1/*- 2 * Copyright (c) 1994-1995 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 1.4 1995/11/22 07:43:42 bde Exp $ 32 */ 33 34#include <sys/param.h> 35#include <sys/systm.h> 36#include <sys/resourcevar.h> 37#include <sys/exec.h> 38#include <sys/mman.h> 39#include <sys/imgact.h> 40#include <sys/imgact_aout.h> 41#include <sys/kernel.h> 42#include <sys/sysent.h> 43 44#include <vm/vm.h> 45#include <vm/vm_kern.h> 46#include <vm/vm_param.h> 47#include <vm/pmap.h> 48#include <vm/lock.h> 49#include <vm/vm_map.h> 50#include <vm/vm_prot.h> 51 52#include <i386/linux/sysproto.h> 53 54extern int exec_linux_imgact __P((struct image_params *iparams)); 55 56int 57exec_linux_imgact(imgp) 58 struct image_params *imgp; 59{ 60 struct exec *a_out = (struct exec *) imgp->image_header; 61 struct vmspace *vmspace = imgp->proc->p_vmspace; 62 unsigned long vmaddr, virtual_offset, file_offset; 63 unsigned long buffer, bss_size; 64 int error; 65 66 if (((a_out->a_magic >> 16) & 0xff) != 0x64) 67 return -1; 68 69 /* 70 * Set file/virtual offset based on a.out variant. 71 */ 72 switch ((int)(a_out->a_magic & 0xffff)) { 73 case 0413: 74 virtual_offset = 0; 75 file_offset = 1024; 76 break; 77 case 0314: 78 virtual_offset = 4096; 79 file_offset = 0; 80 break; 81 default: 82 return (-1); 83 } 84 bss_size = round_page(a_out->a_bss); 85 86 /* 87 * Check various fields in header for validity/bounds. 88 */ 89 if (a_out->a_entry < virtual_offset || 90 a_out->a_entry >= virtual_offset + a_out->a_text || 91 a_out->a_text % NBPG || a_out->a_data % NBPG) 92 return (-1); 93 94 /* text + data can't exceed file size */ 95 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 96 return (EFAULT); 97 /* 98 * text/data/bss must not exceed limits 99 */ 100 if (a_out->a_text > MAXTSIZ || a_out->a_data + bss_size > MAXDSIZ || 101 a_out->a_data+bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 102 return (ENOMEM); 103 104 /* copy in arguments and/or environment from old process */ 105 error = exec_extract_strings(imgp); 106 if (error) 107 return (error); 108 109 /* 110 * Destroy old process VM and create a new one (with a new stack) 111 */ 112 exec_new_vmspace(imgp); 113 114 /* 115 * Check if file_offset page aligned,. 116 * Currently we cannot handle misalinged file offsets, 117 * and so we read in the entire image (what a waste). 118 */ 119 if (file_offset & PGOFSET) { 120#ifdef DEBUG 121 printf("imgact: Non page aligned binary %d\n", file_offset); 122#endif 123 /* 124 * Map text read/execute 125 */ 126 vmaddr = virtual_offset; 127 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 128 round_page(a_out->a_text), FALSE); 129 if (error) 130 return error; 131 132 error = vm_mmap(kernel_map, &buffer, 133 round_page(a_out->a_text + file_offset), 134 VM_PROT_READ, VM_PROT_READ, MAP_FILE, 135 (caddr_t) imgp->vp, trunc_page(file_offset)); 136 if (error) 137 return error; 138 139 error = copyout((caddr_t)(buffer + file_offset), (caddr_t)vmaddr, 140 a_out->a_text); 141 if (error) 142 return error; 143 144 vm_map_remove(kernel_map, trunc_page(vmaddr), 145 round_page(a_out->a_text + file_offset)); 146 147 error = vm_map_protect(&vmspace->vm_map, vmaddr, 148 round_page(a_out->a_text), 149 VM_PROT_EXECUTE|VM_PROT_READ, TRUE); 150 if (error) 151 return error; 152 /* 153 * Map data read/write 154 */ 155 vmaddr = virtual_offset + a_out->a_text; 156 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 157 round_page(a_out->a_data + bss_size), FALSE); 158 if (error) 159 return error; 160 161 error = vm_mmap(kernel_map, &buffer, 162 round_page(a_out->a_data + file_offset), 163 VM_PROT_READ, VM_PROT_READ, MAP_FILE, 164 (caddr_t) imgp->vp, 165 trunc_page(a_out->a_text + file_offset)); 166 if (error) 167 return error; 168 169 error = copyout((caddr_t)(buffer + file_offset), 170 (caddr_t)vmaddr, 171 a_out->a_data); 172 if (error) 173 return error; 174 175 vm_map_remove(kernel_map, trunc_page(vmaddr), 176 round_page(a_out->a_data + file_offset)); 177 178 error = vm_map_protect(&vmspace->vm_map, vmaddr, 179 round_page(a_out->a_data + bss_size), 180 VM_PROT_WRITE|VM_PROT_READ, TRUE); 181 if (error) 182 return error; 183 } 184 else { 185#ifdef DEBUG 186 printf("imgact: Page aligned binary %d\n", file_offset); 187#endif 188 /* 189 * Map text read/execute 190 */ 191 vmaddr = virtual_offset; 192 error = vm_mmap(&vmspace->vm_map, &vmaddr, a_out->a_text, 193 VM_PROT_READ | VM_PROT_EXECUTE, 194 VM_PROT_READ | VM_PROT_EXECUTE | VM_PROT_WRITE, 195 MAP_PRIVATE | MAP_FIXED, 196 (caddr_t)imgp->vp, file_offset); 197 if (error) 198 return (error); 199 200 /* 201 * Map data read/write 202 */ 203 vmaddr = virtual_offset + a_out->a_text; 204 error = vm_mmap(&vmspace->vm_map, &vmaddr, a_out->a_data, 205 VM_PROT_READ | VM_PROT_WRITE, 206 VM_PROT_ALL, MAP_PRIVATE | MAP_FIXED, 207 (caddr_t)imgp->vp, file_offset + a_out->a_text); 208 if (error) 209 return (error); 210 211 /* 212 * Allocate demand-zeroed area for uninitialized data 213 */ 214 if (bss_size != 0) { 215 vmaddr = virtual_offset + a_out->a_text + a_out->a_data; 216 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 217 bss_size, FALSE); 218 if (error) 219 return (error); 220 } 221 /* Indicate that this file should not be modified */ 222 imgp->vp->v_flag |= VTEXT; 223 } 224 /* Fill in process VM information */ 225 vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT; 226 vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT; 227 vmspace->vm_taddr = (caddr_t)virtual_offset; 228 vmspace->vm_daddr = (caddr_t)virtual_offset + a_out->a_text; 229 230 /* Fill in image_params */ 231 imgp->interpreted = 0; 232 imgp->entry_addr = a_out->a_entry; 233 234 imgp->proc->p_sysent = &linux_sysvec; 235 return (0); 236} 237 238/* 239 * Tell kern_execve.c about it, with a little help from the linker. 240 * Since `const' objects end up in the text segment, TEXT_SET is the 241 * correct directive to use. 242 */ 243const struct execsw linux_execsw = { exec_linux_imgact, "linux" }; 244TEXT_SET(execsw_set, linux_execsw); 245 246