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