imgact_aout.c revision 43402
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 * $Id: imgact_aout.c,v 1.44 1999/01/01 14:41:51 bde Exp $ 27 */ 28 29#include <sys/param.h> 30#include <sys/acct.h> 31#include <sys/resourcevar.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/malloc.h> 38#include <sys/namei.h> 39#include <sys/pioctl.h> 40#include <sys/proc.h> 41#include <sys/signalvar.h> 42#include <sys/stat.h> 43#include <sys/sysent.h> 44#include <sys/syscall.h> 45#include <sys/vnode.h> 46#include <sys/systm.h> 47#include <machine/md_var.h> 48 49#include <vm/vm.h> 50#include <vm/vm_param.h> 51#include <vm/vm_prot.h> 52#include <sys/lock.h> 53#include <vm/pmap.h> 54#include <vm/vm_map.h> 55#include <vm/vm_object.h> 56#include <sys/user.h> 57 58static int exec_aout_imgact __P((struct image_params *imgp)); 59 60struct sysentvec aout_sysvec = { 61 SYS_MAXSYSCALL, 62 sysent, 63 0, 64 0, 65 0, 66 0, 67 0, 68 0, 69 0, 70 sendsig, 71 sigcode, 72 &szsigcode, 73 0, 74 "FreeBSD a.out", 75 aout_coredump 76}; 77 78static int 79exec_aout_imgact(imgp) 80 struct image_params *imgp; 81{ 82 const struct exec *a_out = (const struct exec *) imgp->image_header; 83 struct vmspace *vmspace; 84 struct vnode *vp; 85 vm_object_t object; 86 vm_offset_t text_end, data_end; 87 unsigned long virtual_offset; 88 unsigned long file_offset; 89 unsigned long bss_size; 90 int error; 91 92 /* 93 * Linux and *BSD binaries look very much alike, 94 * only the machine id is different: 95 * 0x64 for Linux, 0x86 for *BSD, 0x00 for BSDI. 96 * NetBSD is in network byte order.. ugh. 97 */ 98 if (((a_out->a_magic >> 16) & 0xff) != 0x86 && 99 ((a_out->a_magic >> 16) & 0xff) != 0 && 100 ((((int)ntohl(a_out->a_magic)) >> 16) & 0xff) != 0x86) 101 return -1; 102 103 /* 104 * Set file/virtual offset based on a.out variant. 105 * We do two cases: host byte order and network byte order 106 * (for NetBSD compatibility) 107 */ 108 switch ((int)(a_out->a_magic & 0xffff)) { 109 case ZMAGIC: 110 virtual_offset = 0; 111 if (a_out->a_text) { 112 file_offset = PAGE_SIZE; 113 } else { 114 /* Bill's "screwball mode" */ 115 file_offset = 0; 116 } 117 break; 118 case QMAGIC: 119 virtual_offset = PAGE_SIZE; 120 file_offset = 0; 121 break; 122 default: 123 /* NetBSD compatibility */ 124 switch ((int)(ntohl(a_out->a_magic) & 0xffff)) { 125 case ZMAGIC: 126 case QMAGIC: 127 virtual_offset = PAGE_SIZE; 128 file_offset = 0; 129 break; 130 default: 131 return (-1); 132 } 133 } 134 135 bss_size = roundup(a_out->a_bss, PAGE_SIZE); 136 137 /* 138 * Check various fields in header for validity/bounds. 139 */ 140 if (/* entry point must lay with text region */ 141 a_out->a_entry < virtual_offset || 142 a_out->a_entry >= virtual_offset + a_out->a_text || 143 144 /* text and data size must each be page rounded */ 145 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK) 146 return (-1); 147 148 /* text + data can't exceed file size */ 149 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 150 return (EFAULT); 151 152 /* 153 * text/data/bss must not exceed limits 154 */ 155 if (/* text can't exceed maximum text size */ 156 a_out->a_text > MAXTSIZ || 157 158 /* data + bss can't exceed rlimit */ 159 a_out->a_data + bss_size > 160 imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 161 return (ENOMEM); 162 163 /* copy in arguments and/or environment from old process */ 164 error = exec_extract_strings(imgp); 165 if (error) 166 return (error); 167 168 /* 169 * Destroy old process VM and create a new one (with a new stack) 170 */ 171 exec_new_vmspace(imgp); 172 173 /* 174 * The vm space can be changed by exec_new_vmspace 175 */ 176 vmspace = imgp->proc->p_vmspace; 177 178 vp = imgp->vp; 179 object = vp->v_object; 180 vm_object_reference(object); 181 182 text_end = virtual_offset + a_out->a_text; 183 error = vm_map_insert(&vmspace->vm_map, object, 184 file_offset, 185 virtual_offset, text_end, 186 VM_PROT_READ | VM_PROT_EXECUTE, VM_PROT_ALL, 187 MAP_COPY_NEEDED | MAP_COPY_ON_WRITE); 188 if (error) 189 return (error); 190 191 data_end = text_end + a_out->a_data; 192 if (a_out->a_data) { 193 vm_object_reference(object); 194 error = vm_map_insert(&vmspace->vm_map, object, 195 file_offset + a_out->a_text, 196 text_end, data_end, 197 VM_PROT_ALL, VM_PROT_ALL, 198 MAP_COPY_NEEDED | MAP_COPY_ON_WRITE); 199 if (error) 200 return (error); 201 } 202 203 pmap_object_init_pt(&vmspace->vm_pmap, virtual_offset, 204 object, (vm_pindex_t) OFF_TO_IDX(file_offset), 205 a_out->a_text + a_out->a_data, 0); 206 207 if (bss_size) { 208 error = vm_map_insert(&vmspace->vm_map, NULL, 0, 209 data_end, data_end + bss_size, 210 VM_PROT_ALL, VM_PROT_ALL, 0); 211 if (error) 212 return (error); 213 } 214 215 /* Fill in process VM information */ 216 vmspace->vm_tsize = a_out->a_text >> PAGE_SHIFT; 217 vmspace->vm_dsize = (a_out->a_data + bss_size) >> PAGE_SHIFT; 218 vmspace->vm_taddr = (caddr_t) (uintptr_t) virtual_offset; 219 vmspace->vm_daddr = (caddr_t) (uintptr_t) 220 (virtual_offset + a_out->a_text); 221 222 /* Fill in image_params */ 223 imgp->interpreted = 0; 224 imgp->entry_addr = a_out->a_entry; 225 226 imgp->proc->p_sysent = &aout_sysvec; 227 228 /* Indicate that this file should not be modified */ 229 imgp->vp->v_flag |= VTEXT; 230 231 return (0); 232} 233 234/* 235 * Dump core, into a file named as described in the comments for 236 * expand_name(), unless the process was setuid/setgid. 237 */ 238int 239aout_coredump(p) 240 register struct proc *p; 241{ 242 register struct vnode *vp; 243 register struct ucred *cred = p->p_cred->pc_ucred; 244 register struct vmspace *vm = p->p_vmspace; 245 struct nameidata nd; 246 struct vattr vattr; 247 int error, error1; 248 char *name; /* name of corefile */ 249 250 STOPEVENT(p, S_CORE, 0); 251 if (sugid_coredump == 0 && p->p_flag & P_SUGID) 252 return (EFAULT); 253 if (ctob(UPAGES + vm->vm_dsize + vm->vm_ssize) >= 254 p->p_rlimit[RLIMIT_CORE].rlim_cur) 255 return (EFAULT); 256 name = expand_name(p->p_comm, p->p_ucred->cr_uid, p->p_pid); 257 if (name == NULL) 258 return (EFAULT); /* XXX -- not the best error */ 259 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, name, p); 260 error = vn_open(&nd, O_CREAT | FWRITE, S_IRUSR | S_IWUSR); 261 free(name, M_TEMP); 262 if (error) 263 return (error); 264 vp = nd.ni_vp; 265 266 /* Don't dump to non-regular files or files with links. */ 267 if (vp->v_type != VREG || 268 VOP_GETATTR(vp, &vattr, cred, p) || vattr.va_nlink != 1) { 269 error = EFAULT; 270 goto out; 271 } 272 VATTR_NULL(&vattr); 273 vattr.va_size = 0; 274 VOP_LEASE(vp, p, cred, LEASE_WRITE); 275 VOP_SETATTR(vp, &vattr, cred, p); 276 p->p_acflag |= ACORE; 277 bcopy(p, &p->p_addr->u_kproc.kp_proc, sizeof(struct proc)); 278 fill_eproc(p, &p->p_addr->u_kproc.kp_eproc); 279 error = cpu_coredump(p, vp, cred); 280 if (error == 0) 281 error = vn_rdwr(UIO_WRITE, vp, vm->vm_daddr, 282 (int)ctob(vm->vm_dsize), (off_t)ctob(UPAGES), UIO_USERSPACE, 283 IO_NODELOCKED|IO_UNIT, cred, (int *) NULL, p); 284 if (error == 0) 285 error = vn_rdwr(UIO_WRITE, vp, 286 (caddr_t) trunc_page(USRSTACK - ctob(vm->vm_ssize)), 287 round_page(ctob(vm->vm_ssize)), 288 (off_t)ctob(UPAGES) + ctob(vm->vm_dsize), UIO_USERSPACE, 289 IO_NODELOCKED|IO_UNIT, cred, (int *) NULL, p); 290out: 291 VOP_UNLOCK(vp, 0, p); 292 error1 = vn_close(vp, FWRITE, cred, p); 293 if (error == 0) 294 error = error1; 295 return (error); 296} 297 298/* 299 * Tell kern_execve.c about it, with a little help from the linker. 300 * Since `const' objects end up in the text segment, TEXT_SET is the 301 * correct directive to use. 302 */ 303static struct execsw aout_execsw = { exec_aout_imgact, "a.out" }; 304EXEC_SET(aout, aout_execsw); 305