imgact_linux.c revision 76166
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 * $FreeBSD: head/sys/i386/linux/imgact_linux.c 76166 2001-05-01 08:13:21Z markm $ 32 */ 33 34#include <sys/param.h> 35#include <sys/systm.h> 36#include <sys/exec.h> 37#include <sys/imgact.h> 38#include <sys/imgact_aout.h> 39#include <sys/kernel.h> 40#include <sys/lock.h> 41#include <sys/mman.h> 42#include <sys/mutex.h> 43#include <sys/proc.h> 44#include <sys/resourcevar.h> 45#include <sys/vnode.h> 46 47#include <vm/vm.h> 48#include <vm/vm_kern.h> 49#include <vm/vm_param.h> 50#include <vm/pmap.h> 51#include <vm/vm_map.h> 52#include <vm/vm_extern.h> 53 54#include <i386/linux/linux.h> 55 56static int exec_linux_imgact __P((struct image_params *iparams)); 57 58static int 59exec_linux_imgact(imgp) 60 struct image_params *imgp; 61{ 62 const struct exec *a_out = (const struct exec *) imgp->image_header; 63 struct vmspace *vmspace; 64 vm_offset_t vmaddr; 65 unsigned long virtual_offset, file_offset; 66 vm_offset_t buffer; 67 unsigned long bss_size; 68 int error; 69 70 if (((a_out->a_magic >> 16) & 0xff) != 0x64) 71 return -1; 72 73 /* 74 * Set file/virtual offset based on a.out variant. 75 */ 76 switch ((int)(a_out->a_magic & 0xffff)) { 77 case 0413: 78 virtual_offset = 0; 79 file_offset = 1024; 80 break; 81 case 0314: 82 virtual_offset = 4096; 83 file_offset = 0; 84 break; 85 default: 86 return (-1); 87 } 88 bss_size = round_page(a_out->a_bss); 89#ifdef DEBUG 90 printf("imgact: text: %08lx, data: %08lx, bss: %08lx\n", 91 (u_long)a_out->a_text, (u_long)a_out->a_data, bss_size); 92#endif 93 94 /* 95 * Check various fields in header for validity/bounds. 96 */ 97 if (a_out->a_entry < virtual_offset || 98 a_out->a_entry >= virtual_offset + a_out->a_text || 99 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK) 100 return (-1); 101 102 /* text + data can't exceed file size */ 103 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 104 return (EFAULT); 105 /* 106 * text/data/bss must not exceed limits 107 */ 108 mtx_assert(&Giant, MA_OWNED); 109 if (a_out->a_text > MAXTSIZ || 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 vmspace = imgp->proc->p_vmspace; 123 124 /* 125 * Check if file_offset page aligned,. 126 * Currently we cannot handle misalinged file offsets, 127 * and so we read in the entire image (what a waste). 128 */ 129 if (file_offset & PAGE_MASK) { 130#ifdef DEBUG 131 printf("imgact: Non page aligned binary %lu\n", file_offset); 132#endif 133 /* 134 * Map text+data+bss read/write/execute 135 */ 136 vmaddr = virtual_offset; 137 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 138 a_out->a_text + a_out->a_data + bss_size, FALSE, 139 VM_PROT_ALL, VM_PROT_ALL, 0); 140 if (error) 141 return error; 142 143 error = vm_mmap(kernel_map, &buffer, 144 round_page(a_out->a_text + a_out->a_data + file_offset), 145 VM_PROT_READ, VM_PROT_READ, 0, 146 (caddr_t) imgp->vp, trunc_page(file_offset)); 147 if (error) 148 return error; 149 150 error = copyout((caddr_t)(void *)(uintptr_t)(buffer + file_offset), 151 (caddr_t)vmaddr, a_out->a_text + a_out->a_data); 152 153 vm_map_remove(kernel_map, buffer, 154 buffer + round_page(a_out->a_text + a_out->a_data + file_offset)); 155 156 if (error) 157 return error; 158 159 /* 160 * remove write enable on the 'text' part 161 */ 162 error = vm_map_protect(&vmspace->vm_map, 163 vmaddr, 164 vmaddr + a_out->a_text, 165 VM_PROT_EXECUTE|VM_PROT_READ, 166 TRUE); 167 if (error) 168 return error; 169 } 170 else { 171#ifdef DEBUG 172 printf("imgact: Page aligned binary %lu\n", file_offset); 173#endif 174 /* 175 * Map text+data read/execute 176 */ 177 vmaddr = virtual_offset; 178 error = vm_mmap(&vmspace->vm_map, &vmaddr, 179 a_out->a_text + a_out->a_data, 180 VM_PROT_READ | VM_PROT_EXECUTE, 181 VM_PROT_ALL, 182 MAP_PRIVATE | MAP_FIXED, 183 (caddr_t)imgp->vp, file_offset); 184 if (error) 185 return (error); 186 187#ifdef DEBUG 188 printf("imgact: startaddr=%08lx, length=%08lx\n", 189 (u_long)vmaddr, a_out->a_text + a_out->a_data); 190#endif 191 /* 192 * allow read/write of data 193 */ 194 error = vm_map_protect(&vmspace->vm_map, 195 vmaddr + a_out->a_text, 196 vmaddr + a_out->a_text + a_out->a_data, 197 VM_PROT_ALL, 198 FALSE); 199 if (error) 200 return (error); 201 202 /* 203 * Allocate anon demand-zeroed area for uninitialized data 204 */ 205 if (bss_size != 0) { 206 vmaddr = virtual_offset + a_out->a_text + a_out->a_data; 207 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 208 bss_size, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0); 209 if (error) 210 return (error); 211#ifdef DEBUG 212 printf("imgact: bssaddr=%08lx, length=%08lx\n", 213 (u_long)vmaddr, bss_size); 214#endif 215 216 } 217 /* Indicate that this file should not be modified */ 218 imgp->vp->v_flag |= VTEXT; 219 } 220 /* Fill in process VM information */ 221 vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT; 222 vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT; 223 vmspace->vm_taddr = (caddr_t)(void *)(uintptr_t)virtual_offset; 224 vmspace->vm_daddr = (caddr_t)(void *)(uintptr_t) 225 (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 */ 238static struct execsw linux_execsw = { exec_linux_imgact, "linux a.out" }; 239EXEC_SET(linuxaout, linux_execsw); 240