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 1.23 1997/07/20 14:21:36 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/vnode.h> 44 45 #include <vm/vm.h> 46 #include <vm/vm_kern.h> 47 #include <vm/vm_param.h> 48 #include <vm/pmap.h> 49 #include <vm/vm_map.h> 50 #include <vm/vm_prot.h> 51 #include <vm/vm_extern.h> 52 53 #include <i386/linux/linux.h> 54 55 extern int exec_linux_imgact __P((struct image_params *iparams)); 56 57 int 58 exec_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: %08x, data: %08x, bss: %08x\n", a_out->a_text, a_out->a_data, bss_size); 90 #endif 91 92 /* 93 * Check various fields in header for validity/bounds. 94 */ 95 if (a_out->a_entry < virtual_offset || 96 a_out->a_entry >= virtual_offset + a_out->a_text || 97 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK) 98 return (-1); 99 100 /* text + data can't exceed file size */ 101 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 102 return (EFAULT); 103 /* 104 * text/data/bss must not exceed limits 105 */ 106 if (a_out->a_text > MAXTSIZ || 107 a_out->a_data + bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 108 return (ENOMEM); 109 110 /* copy in arguments and/or environment from old process */ 111 error = exec_extract_strings(imgp); 112 if (error) 113 return (error); 114 115 /* 116 * Destroy old process VM and create a new one (with a new stack) 117 */ 118 exec_new_vmspace(imgp); 119 vmspace = imgp->proc->p_vmspace; 120 121 /* 122 * Check if file_offset page aligned,. 123 * Currently we cannot handle misalinged file offsets, 124 * and so we read in the entire image (what a waste). 125 */ 126 if (file_offset & PAGE_MASK) { 127 #ifdef DEBUG 128 printf("imgact: Non page aligned binary %d\n", file_offset); 129 #endif 130 /* 131 * Map text+data+bss read/write/execute 132 */ 133 vmaddr = virtual_offset; 134 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 135 a_out->a_text + a_out->a_data + bss_size, FALSE, 136 VM_PROT_ALL, VM_PROT_ALL, 0); 137 if (error) 138 return error; 139 140 error = vm_mmap(kernel_map, &buffer, 141 round_page(a_out->a_text + a_out->a_data + file_offset), 142 VM_PROT_READ, VM_PROT_READ, 0, 143 (caddr_t) imgp->vp, trunc_page(file_offset)); 144 if (error) 145 return error; 146 147 error = copyout((caddr_t)(buffer + file_offset), (caddr_t)vmaddr, 148 a_out->a_text + a_out->a_data); 149 150 vm_map_remove(kernel_map, buffer, 151 buffer + round_page(a_out->a_text + a_out->a_data + file_offset)); 152 153 if (error) 154 return error; 155 156 /* 157 * remove write enable on the 'text' part 158 */ 159 error = vm_map_protect(&vmspace->vm_map, 160 vmaddr, 161 vmaddr + a_out->a_text, 162 VM_PROT_EXECUTE|VM_PROT_READ, 163 TRUE); 164 if (error) 165 return error; 166 } 167 else { 168 #ifdef DEBUG 169 printf("imgact: Page aligned binary %d\n", file_offset); 170 #endif 171 /* 172 * Map text+data read/execute 173 */ 174 vmaddr = virtual_offset; 175 error = vm_mmap(&vmspace->vm_map, &vmaddr, 176 a_out->a_text + a_out->a_data, 177 VM_PROT_READ | VM_PROT_EXECUTE, 178 VM_PROT_ALL, 179 MAP_PRIVATE | MAP_FIXED, 180 (caddr_t)imgp->vp, file_offset); 181 if (error) 182 return (error); 183 184 #ifdef DEBUG 185 printf("imgact: startaddr=%08x, length=%08x\n", vmaddr, a_out->a_text + a_out->a_data); 186 #endif 187 /* 188 * allow read/write of data 189 */ 190 error = vm_map_protect(&vmspace->vm_map, 191 vmaddr + a_out->a_text, 192 vmaddr + a_out->a_text + a_out->a_data, 193 VM_PROT_ALL, 194 FALSE); 195 if (error) 196 return (error); 197 198 /* 199 * Allocate anon demand-zeroed area for uninitialized data 200 */ 201 if (bss_size != 0) { 202 vmaddr = virtual_offset + a_out->a_text + a_out->a_data; 203 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 204 bss_size, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0); 205 if (error) 206 return (error); 207 #ifdef DEBUG 208 printf("imgact: bssaddr=%08x, length=%08x\n", vmaddr, bss_size); 209 #endif 210 211 } 212 /* Indicate that this file should not be modified */ 213 imgp->vp->v_flag |= VTEXT; 214 } 215 /* Fill in process VM information */ 216 vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT; 217 vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT; 218 vmspace->vm_taddr = (caddr_t)virtual_offset; 219 vmspace->vm_daddr = (caddr_t)virtual_offset + a_out->a_text; 220 221 /* Fill in image_params */ 222 imgp->interpreted = 0; 223 imgp->entry_addr = a_out->a_entry; 224 225 imgp->proc->p_sysent = &linux_sysvec; 226 return (0); 227 } 228 229 /* 230 * Tell kern_execve.c about it, with a little help from the linker. 231 * Since `const' objects end up in the text segment, TEXT_SET is the 232 * correct directive to use. 233 */ 234 const struct execsw linux_execsw = { exec_linux_imgact, "linux a.out" }; 235 TEXT_SET(execsw_set, linux_execsw); 236 237