imgact_svr4.c revision 116174
1/*- 2 * Copyright (c) 1998 Mark Newton 3 * Copyright (c) 1994-1996 S�ren Schmidt 4 * All rights reserved. 5 * 6 * Based heavily on /sys/kern/imgact_aout.c which is: 7 * Copyright (c) 1993, David Greenman 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer 14 * in this position and unchanged. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD: head/sys/compat/svr4/imgact_svr4.c 116174 2003-06-10 21:44:29Z obrien $"); 35 36#include <sys/param.h> 37#include <sys/systm.h> 38#include <sys/exec.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/mman.h> 44#include <sys/mutex.h> 45#include <sys/proc.h> 46#include <sys/resourcevar.h> 47#include <sys/vnode.h> 48 49#include <vm/vm.h> 50#include <vm/vm_kern.h> 51#include <vm/vm_param.h> 52#include <vm/pmap.h> 53#include <vm/vm_map.h> 54#include <vm/vm_extern.h> 55 56#include <compat/svr4/svr4.h> 57 58static int exec_svr4_imgact(struct image_params *iparams); 59 60static int 61exec_svr4_imgact(imgp) 62 struct image_params *imgp; 63{ 64 const struct exec *a_out = (const struct exec *) imgp->image_header; 65 struct vmspace *vmspace; 66 vm_offset_t vmaddr; 67 unsigned long virtual_offset, file_offset; 68 vm_offset_t buffer; 69 unsigned long bss_size; 70 int error; 71 struct thread *td = curthread; 72 73 if (((a_out->a_magic >> 16) & 0xff) != 0x64) 74 return -1; 75 76 /* 77 * Set file/virtual offset based on a.out variant. 78 */ 79 switch ((int)(a_out->a_magic & 0xffff)) { 80 case 0413: 81 virtual_offset = 0; 82 file_offset = 1024; 83 break; 84 case 0314: 85 virtual_offset = 4096; 86 file_offset = 0; 87 break; 88 default: 89 return (-1); 90 } 91 bss_size = round_page(a_out->a_bss); 92#ifdef DEBUG 93 printf("imgact: text: %08lx, data: %08lx, bss: %08lx\n", a_out->a_text, a_out->a_data, bss_size); 94#endif 95 96 /* 97 * Check various fields in header for validity/bounds. 98 */ 99 if (a_out->a_entry < virtual_offset || 100 a_out->a_entry >= virtual_offset + a_out->a_text || 101 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK) 102 return (-1); 103 104 /* text + data can't exceed file size */ 105 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 106 return (EFAULT); 107 /* For p_rlimit below. */ 108 mtx_assert(&Giant, MA_OWNED); 109 /* 110 * text/data/bss must not exceed limits 111 */ 112 if (a_out->a_text > maxtsiz || 113 a_out->a_data + bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 114 return (ENOMEM); 115 116 VOP_UNLOCK(imgp->vp, 0, td); 117 118 /* copy in arguments and/or environment from old process */ 119 error = exec_extract_strings(imgp); 120 if (error) 121 goto fail; 122 123 /* 124 * Destroy old process VM and create a new one (with a new stack) 125 */ 126 exec_new_vmspace(imgp, &svr4_sysvec); 127 vmspace = imgp->proc->p_vmspace; 128 129 /* 130 * Check if file_offset page aligned,. 131 * Currently we cannot handle misalinged file offsets, 132 * and so we read in the entire image (what a waste). 133 */ 134 if (file_offset & PAGE_MASK) { 135#ifdef DEBUG 136 printf("imgact: Non page aligned binary %lu\n", file_offset); 137#endif 138 /* 139 * Map text+data+bss read/write/execute 140 */ 141 vmaddr = virtual_offset; 142 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 143 a_out->a_text + a_out->a_data + bss_size, FALSE, 144 VM_PROT_ALL, VM_PROT_ALL, 0); 145 if (error) 146 goto fail; 147 148 error = vm_mmap(kernel_map, &buffer, 149 round_page(a_out->a_text + a_out->a_data + file_offset), 150 VM_PROT_READ, VM_PROT_READ, 0, 151 (caddr_t) imgp->vp, trunc_page(file_offset)); 152 if (error) 153 goto fail; 154 155 error = copyout((caddr_t)(buffer + file_offset), (caddr_t)vmaddr, 156 a_out->a_text + a_out->a_data); 157 158 vm_map_remove(kernel_map, buffer, 159 buffer + round_page(a_out->a_text + a_out->a_data + file_offset)); 160 161 if (error) 162 goto fail; 163 164 /* 165 * remove write enable on the 'text' part 166 */ 167 error = vm_map_protect(&vmspace->vm_map, 168 vmaddr, 169 vmaddr + a_out->a_text, 170 VM_PROT_EXECUTE|VM_PROT_READ, 171 TRUE); 172 if (error) 173 goto fail; 174 } 175 else { 176#ifdef DEBUG 177 printf("imgact: Page aligned binary %lu\n", file_offset); 178#endif 179 /* 180 * Map text+data read/execute 181 */ 182 vmaddr = virtual_offset; 183 error = vm_mmap(&vmspace->vm_map, &vmaddr, 184 a_out->a_text + a_out->a_data, 185 VM_PROT_READ | VM_PROT_EXECUTE, 186 VM_PROT_ALL, 187 MAP_PRIVATE | MAP_FIXED, 188 (caddr_t)imgp->vp, file_offset); 189 if (error) 190 goto fail; 191 192#ifdef DEBUG 193 printf("imgact: startaddr=%08lx, length=%08lx\n", (u_long)vmaddr, 194 a_out->a_text + a_out->a_data); 195#endif 196 /* 197 * allow read/write of data 198 */ 199 error = vm_map_protect(&vmspace->vm_map, 200 vmaddr + a_out->a_text, 201 vmaddr + a_out->a_text + a_out->a_data, 202 VM_PROT_ALL, 203 FALSE); 204 if (error) 205 goto fail; 206 207 /* 208 * Allocate anon demand-zeroed area for uninitialized data 209 */ 210 if (bss_size != 0) { 211 vmaddr = virtual_offset + a_out->a_text + a_out->a_data; 212 error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr, 213 bss_size, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0); 214 if (error) 215 goto fail; 216#ifdef DEBUG 217 printf("imgact: bssaddr=%08lx, length=%08lx\n", 218 (u_long)vmaddr, bss_size); 219#endif 220 221 } 222 } 223 /* Fill in process VM information */ 224 vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT; 225 vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT; 226 vmspace->vm_taddr = (caddr_t)virtual_offset; 227 vmspace->vm_daddr = (caddr_t)virtual_offset + a_out->a_text; 228 229 /* Fill in image_params */ 230 imgp->interpreted = 0; 231 imgp->entry_addr = a_out->a_entry; 232 233 imgp->proc->p_sysent = &svr4_sysvec; 234fail: 235 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY, td); 236 return (error); 237} 238 239/* 240 * Tell kern_execve.c about it, with a little help from the linker. 241 */ 242struct execsw svr4_execsw = { exec_svr4_imgact, "svr4 ELF" }; 243EXEC_SET(execsw_set, svr4_execsw); 244 245