imgact_aout.c revision 101941
1/* 2 * Copyright (c) 1993, David Greenman 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: head/sys/kern/imgact_aout.c 101941 2002-08-15 20:55:08Z rwatson $ 27 */ 28 29#include "opt_kstack_pages.h" 30 31#include <sys/param.h> 32#include <sys/exec.h> 33#include <sys/fcntl.h> 34#include <sys/imgact.h> 35#include <sys/imgact_aout.h> 36#include <sys/kernel.h> 37#include <sys/lock.h> 38#include <sys/mutex.h> 39#include <sys/namei.h> 40#include <sys/pioctl.h> 41#include <sys/proc.h> 42#include <sys/resourcevar.h> 43#include <sys/systm.h> 44#include <sys/signalvar.h> 45#include <sys/stat.h> 46#include <sys/sysent.h> 47#include <sys/syscall.h> 48#include <sys/vnode.h> 49#include <sys/user.h> 50 51#include <machine/md_var.h> 52 53#include <vm/vm.h> 54#include <vm/vm_param.h> 55#include <vm/pmap.h> 56#include <vm/vm_map.h> 57#include <vm/vm_object.h> 58 59static int exec_aout_imgact(struct image_params *imgp); 60 61struct sysentvec aout_sysvec = { 62 SYS_MAXSYSCALL, 63 sysent, 64 0, 65 0, 66 0, 67 0, 68 0, 69 0, 70 0, 71 sendsig, 72 sigcode, 73 &szsigcode, 74 0, 75 "FreeBSD a.out", 76 aout_coredump, 77 NULL, 78 MINSIGSTKSZ 79}; 80 81static int 82exec_aout_imgact(imgp) 83 struct image_params *imgp; 84{ 85 const struct exec *a_out = (const struct exec *) imgp->image_header; 86 struct vmspace *vmspace; 87 struct vnode *vp; 88 vm_map_t map; 89 vm_object_t object; 90 vm_offset_t text_end, data_end; 91 unsigned long virtual_offset; 92 unsigned long file_offset; 93 unsigned long bss_size; 94 int error; 95 96 GIANT_REQUIRED; 97 98 /* 99 * Linux and *BSD binaries look very much alike, 100 * only the machine id is different: 101 * 0x64 for Linux, 0x86 for *BSD, 0x00 for BSDI. 102 * NetBSD is in network byte order.. ugh. 103 */ 104 if (((a_out->a_magic >> 16) & 0xff) != 0x86 && 105 ((a_out->a_magic >> 16) & 0xff) != 0 && 106 ((((int)ntohl(a_out->a_magic)) >> 16) & 0xff) != 0x86) 107 return -1; 108 109 /* 110 * Set file/virtual offset based on a.out variant. 111 * We do two cases: host byte order and network byte order 112 * (for NetBSD compatibility) 113 */ 114 switch ((int)(a_out->a_magic & 0xffff)) { 115 case ZMAGIC: 116 virtual_offset = 0; 117 if (a_out->a_text) { 118 file_offset = PAGE_SIZE; 119 } else { 120 /* Bill's "screwball mode" */ 121 file_offset = 0; 122 } 123 break; 124 case QMAGIC: 125 virtual_offset = PAGE_SIZE; 126 file_offset = 0; 127 /* Pass PS_STRINGS for BSD/OS binaries only. */ 128 if (N_GETMID(*a_out) == MID_ZERO) 129 imgp->ps_strings = PS_STRINGS; 130 break; 131 default: 132 /* NetBSD compatibility */ 133 switch ((int)(ntohl(a_out->a_magic) & 0xffff)) { 134 case ZMAGIC: 135 case QMAGIC: 136 virtual_offset = PAGE_SIZE; 137 file_offset = 0; 138 break; 139 default: 140 return (-1); 141 } 142 } 143 144 bss_size = roundup(a_out->a_bss, PAGE_SIZE); 145 146 /* 147 * Check various fields in header for validity/bounds. 148 */ 149 if (/* entry point must lay with text region */ 150 a_out->a_entry < virtual_offset || 151 a_out->a_entry >= virtual_offset + a_out->a_text || 152 153 /* text and data size must each be page rounded */ 154 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK) 155 return (-1); 156 157 /* text + data can't exceed file size */ 158 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 159 return (EFAULT); 160 161 /* 162 * text/data/bss must not exceed limits 163 */ 164 mtx_assert(&Giant, MA_OWNED); 165 if (/* text can't exceed maximum text size */ 166 a_out->a_text > maxtsiz || 167 168 /* data + bss can't exceed rlimit */ 169 a_out->a_data + bss_size > 170 imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 171 return (ENOMEM); 172 173 /* copy in arguments and/or environment from old process */ 174 error = exec_extract_strings(imgp); 175 if (error) 176 return (error); 177 178 /* 179 * Destroy old process VM and create a new one (with a new stack) 180 */ 181 exec_new_vmspace(imgp, VM_MIN_ADDRESS, VM_MAXUSER_ADDRESS, USRSTACK); 182 183 /* 184 * The vm space can be changed by exec_new_vmspace 185 */ 186 vmspace = imgp->proc->p_vmspace; 187 188 vp = imgp->vp; 189 object = imgp->object; 190 map = &vmspace->vm_map; 191 vm_map_lock(map); 192 vm_object_reference(object); 193 194 text_end = virtual_offset + a_out->a_text; 195 error = vm_map_insert(map, object, 196 file_offset, 197 virtual_offset, text_end, 198 VM_PROT_READ | VM_PROT_EXECUTE, VM_PROT_ALL, 199 MAP_COPY_ON_WRITE | MAP_PREFAULT); 200 if (error) { 201 vm_map_unlock(map); 202 return (error); 203 } 204 data_end = text_end + a_out->a_data; 205 if (a_out->a_data) { 206 vm_object_reference(object); 207 error = vm_map_insert(map, object, 208 file_offset + a_out->a_text, 209 text_end, data_end, 210 VM_PROT_ALL, VM_PROT_ALL, 211 MAP_COPY_ON_WRITE | MAP_PREFAULT); 212 if (error) { 213 vm_map_unlock(map); 214 return (error); 215 } 216 } 217 218 if (bss_size) { 219 error = vm_map_insert(map, NULL, 0, 220 data_end, data_end + bss_size, 221 VM_PROT_ALL, VM_PROT_ALL, 0); 222 if (error) { 223 vm_map_unlock(map); 224 return (error); 225 } 226 } 227 vm_map_unlock(map); 228 229 /* Fill in process VM information */ 230 vmspace->vm_tsize = a_out->a_text >> PAGE_SHIFT; 231 vmspace->vm_dsize = (a_out->a_data + bss_size) >> PAGE_SHIFT; 232 vmspace->vm_taddr = (caddr_t) (uintptr_t) virtual_offset; 233 vmspace->vm_daddr = (caddr_t) (uintptr_t) 234 (virtual_offset + a_out->a_text); 235 236 /* Fill in image_params */ 237 imgp->interpreted = 0; 238 imgp->entry_addr = a_out->a_entry; 239 240 imgp->proc->p_sysent = &aout_sysvec; 241 242 return (0); 243} 244 245/* 246 * Dump core, into a file named as described in the comments for 247 * expand_name(), unless the process was setuid/setgid. 248 */ 249int 250aout_coredump(td, vp, limit) 251 register struct thread *td; 252 register struct vnode *vp; 253 off_t limit; 254{ 255 struct proc *p = td->td_proc; 256 register struct ucred *cred = td->td_ucred; 257 register struct vmspace *vm = p->p_vmspace; 258 int error; 259 260 if (ctob((UAREA_PAGES + KSTACK_PAGES) 261 + vm->vm_dsize + vm->vm_ssize) >= limit) 262 return (EFAULT); 263 PROC_LOCK(p); 264 fill_kinfo_proc(p, &p->p_uarea->u_kproc); 265 PROC_UNLOCK(p); 266 error = cpu_coredump(td, vp, cred); 267 if (error == 0) 268 error = vn_rdwr(UIO_WRITE, vp, vm->vm_daddr, 269 (int)ctob(vm->vm_dsize), 270 (off_t)ctob(UAREA_PAGES + KSTACK_PAGES), UIO_USERSPACE, 271 IO_UNIT | IO_DIRECT, cred, NOCRED, (int *) NULL, td); 272 if (error == 0) 273 error = vn_rdwr_inchunks(UIO_WRITE, vp, 274 (caddr_t) trunc_page(USRSTACK - ctob(vm->vm_ssize)), 275 round_page(ctob(vm->vm_ssize)), 276 (off_t)ctob(UAREA_PAGES + KSTACK_PAGES) + 277 ctob(vm->vm_dsize), UIO_USERSPACE, 278 IO_UNIT | IO_DIRECT, cred, NOCRED, (int *) NULL, td); 279 return (error); 280} 281 282/* 283 * Tell kern_execve.c about it, with a little help from the linker. 284 */ 285static struct execsw aout_execsw = { exec_aout_imgact, "a.out" }; 286EXEC_SET(aout, aout_execsw); 287