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 * $FreeBSD$ 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_prot.h> 52 #include <vm/vm_extern.h> 53 54 #include <i386/linux/linux.h> 55 56 static int exec_linux_imgact __P((struct image_params *iparams)); 57 58 static int 59 exec_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 if (a_out->a_text > MAXTSIZ || 109 a_out->a_data + bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 110 return (ENOMEM); 111 112 /* copy in arguments and/or environment from old process */ 113 error = exec_extract_strings(imgp); 114 if (error) 115 return (error); 116 117 /* 118 * Destroy old process VM and create a new one (with a new stack) 119 */ 120 exec_new_vmspace(imgp); 121 vmspace = imgp->proc->p_vmspace; 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 & PAGE_MASK) { 129 #ifdef DEBUG 130 printf("imgact: Non page aligned binary %lu\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)(void *)(uintptr_t)(buffer + file_offset), 150 (caddr_t)vmaddr, 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 %lu\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=%08lx, length=%08lx\n", 188 (u_long)vmaddr, a_out->a_text + a_out->a_data); 189 #endif 190 /* 191 * allow read/write of data 192 */ 193 error = vm_map_protect(&vmspace->vm_map, 194 vmaddr + a_out->a_text, 195 vmaddr + a_out->a_text + a_out->a_data, 196 VM_PROT_ALL, 197 FALSE); 198 if (error) 199 return (error); 200 201 /* 202 * Allocate anon demand-zeroed area for uninitialized data 203 */ 204 if (bss_size != 0) { 205 vmaddr = virtual_offset + a_out->a_text + a_out->a_data; 206 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 207 bss_size, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0); 208 if (error) 209 return (error); 210 #ifdef DEBUG 211 printf("imgact: bssaddr=%08lx, length=%08lx\n", 212 (u_long)vmaddr, bss_size); 213 #endif 214 215 } 216 /* Indicate that this file should not be modified */ 217 imgp->vp->v_flag |= VTEXT; 218 } 219 /* Fill in process VM information */ 220 vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT; 221 vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT; 222 vmspace->vm_taddr = (caddr_t)(void *)(uintptr_t)virtual_offset; 223 vmspace->vm_daddr = (caddr_t)(void *)(uintptr_t) 224 (virtual_offset + a_out->a_text); 225 226 /* Fill in image_params */ 227 imgp->interpreted = 0; 228 imgp->entry_addr = a_out->a_entry; 229 230 imgp->proc->p_sysent = &linux_sysvec; 231 return (0); 232 } 233 234 /* 235 * Tell kern_execve.c about it, with a little help from the linker. 236 */ 237 static struct execsw linux_execsw = { exec_linux_imgact, "linux a.out" }; 238 EXEC_SET(linuxaout, linux_execsw); 239