imgact_linux.c revision 15494
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 1.13 1996/03/19 15:02:33 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/proc.h> 43#include <sys/sysent.h> 44#include <sys/vnode.h> 45 46#include <vm/vm.h> 47#include <vm/vm_kern.h> 48#include <vm/vm_param.h> 49#include <vm/pmap.h> 50#include <vm/lock.h> 51#include <vm/vm_map.h> 52#include <vm/vm_prot.h> 53#include <vm/vm_extern.h> 54 55#include <i386/linux/linux.h> 56#include <i386/linux/linux_proto.h> 57 58extern int exec_linux_imgact __P((struct image_params *iparams)); 59 60int 61exec_linux_imgact(imgp) 62 struct image_params *imgp; 63{ 64 struct exec *a_out = (struct exec *) imgp->image_header; 65 struct vmspace *vmspace = imgp->proc->p_vmspace; 66 vm_offset_t vmaddr; 67 unsigned long virtual_offset, file_offset; 68 vm_offset_t buffer; 69 unsigned long bss_size; 70 int error; 71 72 if (((a_out->a_magic >> 16) & 0xff) != 0x64) 73 return -1; 74 75 /* 76 * Set file/virtual offset based on a.out variant. 77 */ 78 switch ((int)(a_out->a_magic & 0xffff)) { 79 case 0413: 80 virtual_offset = 0; 81 file_offset = 1024; 82 break; 83 case 0314: 84 virtual_offset = 4096; 85 file_offset = 0; 86 break; 87 default: 88 return (-1); 89 } 90 bss_size = round_page(a_out->a_bss); 91#ifdef DEBUG 92 printf("imgact: text: %08x, data: %08x, bss: %08x\n", a_out->a_text, a_out->a_data, bss_size); 93#endif 94 95 /* 96 * Check various fields in header for validity/bounds. 97 */ 98 if (a_out->a_entry < virtual_offset || 99 a_out->a_entry >= virtual_offset + a_out->a_text || 100 a_out->a_text % NBPG || a_out->a_data % NBPG) 101 return (-1); 102 103 /* text + data can't exceed file size */ 104 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 105 return (EFAULT); 106 /* 107 * text/data/bss must not exceed limits 108 */ 109 if (a_out->a_text > MAXTSIZ || a_out->a_data + bss_size > MAXDSIZ || 110 a_out->a_data+bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 111 return (ENOMEM); 112 113 /* copy in arguments and/or environment from old process */ 114 error = exec_extract_strings(imgp); 115 if (error) 116 return (error); 117 118 /* 119 * Destroy old process VM and create a new one (with a new stack) 120 */ 121 exec_new_vmspace(imgp); 122 123 /* 124 * Check if file_offset page aligned,. 125 * Currently we cannot handle misalinged file offsets, 126 * and so we read in the entire image (what a waste). 127 */ 128 if (file_offset & PGOFSET) { 129#ifdef DEBUG 130 printf("imgact: Non page aligned binary %d\n", file_offset); 131#endif 132 /* 133 * Map text+data+bss read/write/execute 134 */ 135 vmaddr = virtual_offset; 136 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 137 a_out->a_text + a_out->a_data + bss_size, FALSE, 138 VM_PROT_ALL, VM_PROT_ALL, 0); 139 if (error) 140 return error; 141 142 error = vm_mmap(kernel_map, &buffer, 143 round_page(a_out->a_text + a_out->a_data + file_offset), 144 VM_PROT_READ, VM_PROT_READ, 0, 145 (caddr_t) imgp->vp, trunc_page(file_offset)); 146 if (error) 147 return error; 148 149 error = copyout((caddr_t)(buffer + file_offset), (caddr_t)vmaddr, 150 a_out->a_text + a_out->a_data); 151 152 vm_map_remove(kernel_map, buffer, 153 buffer + round_page(a_out->a_text + a_out->a_data + file_offset)); 154 155 if (error) 156 return error; 157 158 /* 159 * remove write enable on the 'text' part 160 */ 161 error = vm_map_protect(&vmspace->vm_map, 162 vmaddr, 163 vmaddr + a_out->a_text, 164 VM_PROT_EXECUTE|VM_PROT_READ, 165 TRUE); 166 if (error) 167 return error; 168 } 169 else { 170#ifdef DEBUG 171 printf("imgact: Page aligned binary %d\n", file_offset); 172#endif 173 /* 174 * Map text+data read/execute 175 */ 176 vmaddr = virtual_offset; 177 error = vm_mmap(&vmspace->vm_map, &vmaddr, 178 a_out->a_text + a_out->a_data, 179 VM_PROT_READ | VM_PROT_EXECUTE, 180 VM_PROT_ALL, 181 MAP_PRIVATE | MAP_FIXED, 182 (caddr_t)imgp->vp, file_offset); 183 if (error) 184 return (error); 185 186#ifdef DEBUG 187 printf("imgact: startaddr=%08x, length=%08x\n", vmaddr, a_out->a_text + a_out->a_data); 188#endif 189 /* 190 * allow read/write of data 191 */ 192 error = vm_map_protect(&vmspace->vm_map, 193 vmaddr + a_out->a_text, 194 vmaddr + a_out->a_text + a_out->a_data, 195 VM_PROT_ALL, 196 FALSE); 197 if (error) 198 return (error); 199 200 /* 201 * Allocate anon demand-zeroed area for uninitialized data 202 */ 203 if (bss_size != 0) { 204 vmaddr = virtual_offset + a_out->a_text + a_out->a_data; 205 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 206 bss_size, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0); 207 if (error) 208 return (error); 209#ifdef DEBUG 210 printf("imgact: bssaddr=%08x, length=%08x\n", vmaddr, bss_size); 211#endif 212 213 } 214 /* Indicate that this file should not be modified */ 215 imgp->vp->v_flag |= VTEXT; 216 } 217 /* Fill in process VM information */ 218 vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT; 219 vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT; 220 vmspace->vm_taddr = (caddr_t)virtual_offset; 221 vmspace->vm_daddr = (caddr_t)virtual_offset + a_out->a_text; 222 223 /* Fill in image_params */ 224 imgp->interpreted = 0; 225 imgp->entry_addr = a_out->a_entry; 226 227 imgp->proc->p_sysent = &linux_sysvec; 228 return (0); 229} 230 231/* 232 * Tell kern_execve.c about it, with a little help from the linker. 233 * Since `const' objects end up in the text segment, TEXT_SET is the 234 * correct directive to use. 235 */ 236const struct execsw linux_execsw = { exec_linux_imgact, "linux a.out" }; 237TEXT_SET(execsw_set, linux_execsw); 238 239