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 1.21 1997/04/01 08:39:05 bde 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/vm_map.h> 55 #include <vm/vm_prot.h> 56 #include <vm/vm_extern.h> 57 58 #include <i386/linux/linux.h> 59 #include <i386/linux/linux_proto.h> 60 61 extern int exec_linux_imgact __P((struct image_params *iparams)); 62 63 int 64 exec_linux_imgact(imgp) 65 struct image_params *imgp; 66 { 67 const struct exec *a_out = (const struct exec *) imgp->image_header; 68 struct vmspace *vmspace; 69 vm_offset_t vmaddr; 70 unsigned long virtual_offset, file_offset; 71 vm_offset_t buffer; 72 unsigned long bss_size; 73 int error; 74 75 if (((a_out->a_magic >> 16) & 0xff) != 0x64) 76 return -1; 77 78 /* 79 * Set file/virtual offset based on a.out variant. 80 */ 81 switch ((int)(a_out->a_magic & 0xffff)) { 82 case 0413: 83 virtual_offset = 0; 84 file_offset = 1024; 85 break; 86 case 0314: 87 virtual_offset = 4096; 88 file_offset = 0; 89 break; 90 default: 91 return (-1); 92 } 93 bss_size = round_page(a_out->a_bss); 94 #ifdef DEBUG 95 printf("imgact: text: %08x, data: %08x, bss: %08x\n", a_out->a_text, a_out->a_data, bss_size); 96 #endif 97 98 /* 99 * Check various fields in header for validity/bounds. 100 */ 101 if (a_out->a_entry < virtual_offset || 102 a_out->a_entry >= virtual_offset + a_out->a_text || 103 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK) 104 return (-1); 105 106 /* text + data can't exceed file size */ 107 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 108 return (EFAULT); 109 /* 110 * text/data/bss must not exceed limits 111 */ 112 if (a_out->a_text > MAXTSIZ || a_out->a_data + bss_size > MAXDSIZ || 113 a_out->a_data+bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 114 return (ENOMEM); 115 116 /* copy in arguments and/or environment from old process */ 117 error = exec_extract_strings(imgp); 118 if (error) 119 return (error); 120 121 /* 122 * Destroy old process VM and create a new one (with a new stack) 123 */ 124 exec_new_vmspace(imgp); 125 vmspace = imgp->proc->p_vmspace; 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 */ 240 const struct execsw linux_execsw = { exec_linux_imgact, "linux a.out" }; 241 TEXT_SET(execsw_set, linux_execsw); 242 243