imgact_linux.c revision 52635
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 52635 1999-10-29 18:09:36Z phk $ 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/lock.h> 43#include <sys/proc.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/vm_map.h> 51#include <vm/vm_extern.h> 52 53#include <i386/linux/linux.h> 54 55static int exec_linux_imgact __P((struct image_params *iparams)); 56 57static int 58exec_linux_imgact(imgp) 59 struct image_params *imgp; 60{ 61 const struct exec *a_out = (const struct exec *) imgp->image_header; 62 struct vmspace *vmspace; 63 vm_offset_t vmaddr; 64 unsigned long virtual_offset, file_offset; 65 vm_offset_t buffer; 66 unsigned long bss_size; 67 int error; 68 69 if (((a_out->a_magic >> 16) & 0xff) != 0x64) 70 return -1; 71 72 /* 73 * Set file/virtual offset based on a.out variant. 74 */ 75 switch ((int)(a_out->a_magic & 0xffff)) { 76 case 0413: 77 virtual_offset = 0; 78 file_offset = 1024; 79 break; 80 case 0314: 81 virtual_offset = 4096; 82 file_offset = 0; 83 break; 84 default: 85 return (-1); 86 } 87 bss_size = round_page(a_out->a_bss); 88#ifdef DEBUG 89 printf("imgact: text: %08lx, data: %08lx, bss: %08lx\n", 90 (u_long)a_out->a_text, (u_long)a_out->a_data, bss_size); 91#endif 92 93 /* 94 * Check various fields in header for validity/bounds. 95 */ 96 if (a_out->a_entry < virtual_offset || 97 a_out->a_entry >= virtual_offset + a_out->a_text || 98 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK) 99 return (-1); 100 101 /* text + data can't exceed file size */ 102 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 103 return (EFAULT); 104 /* 105 * text/data/bss must not exceed limits 106 */ 107 if (a_out->a_text > MAXTSIZ || 108 a_out->a_data + bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 109 return (ENOMEM); 110 111 /* copy in arguments and/or environment from old process */ 112 error = exec_extract_strings(imgp); 113 if (error) 114 return (error); 115 116 /* 117 * Destroy old process VM and create a new one (with a new stack) 118 */ 119 exec_new_vmspace(imgp); 120 vmspace = imgp->proc->p_vmspace; 121 122 /* 123 * Check if file_offset page aligned,. 124 * Currently we cannot handle misalinged file offsets, 125 * and so we read in the entire image (what a waste). 126 */ 127 if (file_offset & PAGE_MASK) { 128#ifdef DEBUG 129 printf("imgact: Non page aligned binary %lu\n", file_offset); 130#endif 131 /* 132 * Map text+data+bss read/write/execute 133 */ 134 vmaddr = virtual_offset; 135 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 136 a_out->a_text + a_out->a_data + bss_size, FALSE, 137 VM_PROT_ALL, VM_PROT_ALL, 0); 138 if (error) 139 return error; 140 141 error = vm_mmap(kernel_map, &buffer, 142 round_page(a_out->a_text + a_out->a_data + file_offset), 143 VM_PROT_READ, VM_PROT_READ, 0, 144 (caddr_t) imgp->vp, trunc_page(file_offset)); 145 if (error) 146 return error; 147 148 error = copyout((caddr_t)(void *)(uintptr_t)(buffer + file_offset), 149 (caddr_t)vmaddr, a_out->a_text + a_out->a_data); 150 151 vm_map_remove(kernel_map, buffer, 152 buffer + round_page(a_out->a_text + a_out->a_data + file_offset)); 153 154 if (error) 155 return error; 156 157 /* 158 * remove write enable on the 'text' part 159 */ 160 error = vm_map_protect(&vmspace->vm_map, 161 vmaddr, 162 vmaddr + a_out->a_text, 163 VM_PROT_EXECUTE|VM_PROT_READ, 164 TRUE); 165 if (error) 166 return error; 167 } 168 else { 169#ifdef DEBUG 170 printf("imgact: Page aligned binary %lu\n", file_offset); 171#endif 172 /* 173 * Map text+data read/execute 174 */ 175 vmaddr = virtual_offset; 176 error = vm_mmap(&vmspace->vm_map, &vmaddr, 177 a_out->a_text + a_out->a_data, 178 VM_PROT_READ | VM_PROT_EXECUTE, 179 VM_PROT_ALL, 180 MAP_PRIVATE | MAP_FIXED, 181 (caddr_t)imgp->vp, file_offset); 182 if (error) 183 return (error); 184 185#ifdef DEBUG 186 printf("imgact: startaddr=%08lx, length=%08lx\n", 187 (u_long)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=%08lx, length=%08lx\n", 211 (u_long)vmaddr, bss_size); 212#endif 213 214 } 215 /* Indicate that this file should not be modified */ 216 imgp->vp->v_flag |= VTEXT; 217 } 218 /* Fill in process VM information */ 219 vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT; 220 vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT; 221 vmspace->vm_taddr = (caddr_t)(void *)(uintptr_t)virtual_offset; 222 vmspace->vm_daddr = (caddr_t)(void *)(uintptr_t) 223 (virtual_offset + a_out->a_text); 224 225 /* Fill in image_params */ 226 imgp->interpreted = 0; 227 imgp->entry_addr = a_out->a_entry; 228 229 imgp->proc->p_sysent = &linux_sysvec; 230 return (0); 231} 232 233/* 234 * Tell kern_execve.c about it, with a little help from the linker. 235 */ 236static struct execsw linux_execsw = { exec_linux_imgact, "linux a.out" }; 237EXEC_SET(linuxaout, linux_execsw); 238