imgact_aout.c revision 120422
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 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/sys/kern/imgact_aout.c 120422 2003-09-25 01:10:26Z peter $"); 29 30#include <sys/param.h> 31#include <sys/exec.h> 32#include <sys/imgact.h> 33#include <sys/imgact_aout.h> 34#include <sys/kernel.h> 35#include <sys/lock.h> 36#include <sys/malloc.h> 37#include <sys/mutex.h> 38#include <sys/proc.h> 39#include <sys/resourcevar.h> 40#include <sys/signalvar.h> 41#include <sys/syscall.h> 42#include <sys/sysent.h> 43#include <sys/systm.h> 44#include <sys/vnode.h> 45#include <sys/user.h> 46 47#include <machine/frame.h> 48#include <machine/md_var.h> 49 50#include <vm/vm.h> 51#include <vm/pmap.h> 52#include <vm/vm_map.h> 53#include <vm/vm_object.h> 54#include <vm/vm_param.h> 55 56static int exec_aout_imgact(struct image_params *imgp); 57static int aout_fixup(register_t **stack_base, struct image_params *imgp); 58 59struct sysentvec aout_sysvec = { 60 SYS_MAXSYSCALL, 61 sysent, 62 0, 63 0, 64 NULL, 65 0, 66 NULL, 67 NULL, 68 aout_fixup, 69 sendsig, 70 sigcode, 71 &szsigcode, 72 NULL, 73 "FreeBSD a.out", 74 aout_coredump, 75 NULL, 76 MINSIGSTKSZ, 77 PAGE_SIZE, 78 VM_MIN_ADDRESS, 79 VM_MAXUSER_ADDRESS, 80 USRSTACK, 81 PS_STRINGS, 82 VM_PROT_ALL, 83 exec_copyout_strings, 84 exec_setregs, 85 NULL 86}; 87 88static int 89aout_fixup(stack_base, imgp) 90 register_t **stack_base; 91 struct image_params *imgp; 92{ 93 94 return (suword(--(*stack_base), imgp->argc)); 95} 96 97static int 98exec_aout_imgact(imgp) 99 struct image_params *imgp; 100{ 101 const struct exec *a_out = (const struct exec *) imgp->image_header; 102 struct vmspace *vmspace; 103 struct vnode *vp; 104 vm_map_t map; 105 vm_object_t object; 106 vm_offset_t text_end, data_end; 107 unsigned long virtual_offset; 108 unsigned long file_offset; 109 unsigned long bss_size; 110 int error; 111 112 GIANT_REQUIRED; 113 114 /* 115 * Linux and *BSD binaries look very much alike, 116 * only the machine id is different: 117 * 0x64 for Linux, 0x86 for *BSD, 0x00 for BSDI. 118 * NetBSD is in network byte order.. ugh. 119 */ 120 if (((a_out->a_magic >> 16) & 0xff) != 0x86 && 121 ((a_out->a_magic >> 16) & 0xff) != 0 && 122 ((((int)ntohl(a_out->a_magic)) >> 16) & 0xff) != 0x86) 123 return -1; 124 125 /* 126 * Set file/virtual offset based on a.out variant. 127 * We do two cases: host byte order and network byte order 128 * (for NetBSD compatibility) 129 */ 130 switch ((int)(a_out->a_magic & 0xffff)) { 131 case ZMAGIC: 132 virtual_offset = 0; 133 if (a_out->a_text) { 134 file_offset = PAGE_SIZE; 135 } else { 136 /* Bill's "screwball mode" */ 137 file_offset = 0; 138 } 139 break; 140 case QMAGIC: 141 virtual_offset = PAGE_SIZE; 142 file_offset = 0; 143 /* Pass PS_STRINGS for BSD/OS binaries only. */ 144 if (N_GETMID(*a_out) == MID_ZERO) 145 imgp->ps_strings = aout_sysvec.sv_psstrings; 146 break; 147 default: 148 /* NetBSD compatibility */ 149 switch ((int)(ntohl(a_out->a_magic) & 0xffff)) { 150 case ZMAGIC: 151 case QMAGIC: 152 virtual_offset = PAGE_SIZE; 153 file_offset = 0; 154 break; 155 default: 156 return (-1); 157 } 158 } 159 160 bss_size = roundup(a_out->a_bss, PAGE_SIZE); 161 162 /* 163 * Check various fields in header for validity/bounds. 164 */ 165 if (/* entry point must lay with text region */ 166 a_out->a_entry < virtual_offset || 167 a_out->a_entry >= virtual_offset + a_out->a_text || 168 169 /* text and data size must each be page rounded */ 170 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK) 171 return (-1); 172 173 /* text + data can't exceed file size */ 174 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 175 return (EFAULT); 176 177 /* 178 * text/data/bss must not exceed limits 179 */ 180 mtx_assert(&Giant, MA_OWNED); 181 if (/* text can't exceed maximum text size */ 182 a_out->a_text > maxtsiz || 183 184 /* data + bss can't exceed rlimit */ 185 a_out->a_data + bss_size > 186 imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 187 return (ENOMEM); 188 189 /* copy in arguments and/or environment from old process */ 190 error = exec_extract_strings(imgp); 191 if (error) 192 return (error); 193 194 /* 195 * Destroy old process VM and create a new one (with a new stack) 196 */ 197 exec_new_vmspace(imgp, &aout_sysvec); 198 199 /* 200 * The vm space can be changed by exec_new_vmspace 201 */ 202 vmspace = imgp->proc->p_vmspace; 203 204 vp = imgp->vp; 205 object = imgp->object; 206 map = &vmspace->vm_map; 207 vm_map_lock(map); 208 vm_object_reference(object); 209 210 text_end = virtual_offset + a_out->a_text; 211 error = vm_map_insert(map, object, 212 file_offset, 213 virtual_offset, text_end, 214 VM_PROT_READ | VM_PROT_EXECUTE, VM_PROT_ALL, 215 MAP_COPY_ON_WRITE | MAP_PREFAULT); 216 if (error) { 217 vm_map_unlock(map); 218 return (error); 219 } 220 data_end = text_end + a_out->a_data; 221 if (a_out->a_data) { 222 vm_object_reference(object); 223 error = vm_map_insert(map, object, 224 file_offset + a_out->a_text, 225 text_end, data_end, 226 VM_PROT_ALL, VM_PROT_ALL, 227 MAP_COPY_ON_WRITE | MAP_PREFAULT); 228 if (error) { 229 vm_map_unlock(map); 230 return (error); 231 } 232 } 233 234 if (bss_size) { 235 error = vm_map_insert(map, NULL, 0, 236 data_end, data_end + bss_size, 237 VM_PROT_ALL, VM_PROT_ALL, 0); 238 if (error) { 239 vm_map_unlock(map); 240 return (error); 241 } 242 } 243 vm_map_unlock(map); 244 245 /* Fill in process VM information */ 246 vmspace->vm_tsize = a_out->a_text >> PAGE_SHIFT; 247 vmspace->vm_dsize = (a_out->a_data + bss_size) >> PAGE_SHIFT; 248 vmspace->vm_taddr = (caddr_t) (uintptr_t) virtual_offset; 249 vmspace->vm_daddr = (caddr_t) (uintptr_t) 250 (virtual_offset + a_out->a_text); 251 252 /* Fill in image_params */ 253 imgp->interpreted = 0; 254 imgp->entry_addr = a_out->a_entry; 255 256 imgp->proc->p_sysent = &aout_sysvec; 257 258 return (0); 259} 260 261/* 262 * Dump core, into a file named as described in the comments for 263 * expand_name(), unless the process was setuid/setgid. 264 */ 265int 266aout_coredump(td, vp, limit) 267 register struct thread *td; 268 register struct vnode *vp; 269 off_t limit; 270{ 271 struct proc *p = td->td_proc; 272 register struct ucred *cred = td->td_ucred; 273 register struct vmspace *vm = p->p_vmspace; 274 char *tempuser; 275 int error; 276 277 if (ctob((uarea_pages + kstack_pages) 278 + vm->vm_dsize + vm->vm_ssize) >= limit) 279 return (EFAULT); 280 tempuser = malloc(ctob(uarea_pages + kstack_pages), M_TEMP, 281 M_WAITOK | M_ZERO); 282 if (tempuser == NULL) 283 return (ENOMEM); 284 PROC_LOCK(p); 285 fill_kinfo_proc(p, &p->p_uarea->u_kproc); 286 PROC_UNLOCK(p); 287 bcopy(p->p_uarea, tempuser, sizeof(struct user)); 288 bcopy(td->td_frame, 289 tempuser + ctob(uarea_pages) + 290 ((caddr_t)td->td_frame - (caddr_t)td->td_kstack), 291 sizeof(struct trapframe)); 292 error = vn_rdwr(UIO_WRITE, vp, (caddr_t)tempuser, 293 ctob(uarea_pages + kstack_pages), 294 (off_t)0, UIO_SYSSPACE, IO_UNIT, cred, NOCRED, 295 (int *)NULL, td); 296 free(tempuser, M_TEMP); 297 if (error == 0) 298 error = vn_rdwr(UIO_WRITE, vp, vm->vm_daddr, 299 (int)ctob(vm->vm_dsize), 300 (off_t)ctob(uarea_pages + kstack_pages), UIO_USERSPACE, 301 IO_UNIT | IO_DIRECT, cred, NOCRED, (int *) NULL, td); 302 if (error == 0) 303 error = vn_rdwr_inchunks(UIO_WRITE, vp, 304 (caddr_t)trunc_page(p->p_sysent->sv_usrstack - 305 ctob(vm->vm_ssize)), round_page(ctob(vm->vm_ssize)), 306 (off_t)ctob(uarea_pages + kstack_pages) + 307 ctob(vm->vm_dsize), UIO_USERSPACE, 308 IO_UNIT | IO_DIRECT, cred, NOCRED, (int *) NULL, td); 309 return (error); 310} 311 312/* 313 * Tell kern_execve.c about it, with a little help from the linker. 314 */ 315static struct execsw aout_execsw = { exec_aout_imgact, "a.out" }; 316EXEC_SET(aout, aout_execsw); 317