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/resourcevar.h> 31 #include <sys/exec.h> 32 #include <sys/fcntl.h> 33 #include <sys/imgact.h> 34 #include <sys/imgact_aout.h> 35 #include <sys/kernel.h> 36 #include <sys/malloc.h> 37 #include <sys/namei.h> 38 #include <sys/pioctl.h> 39 #include <sys/proc.h> 40 #include <sys/signalvar.h> 41 #include <sys/stat.h> 42 #include <sys/sysent.h> 43 #include <sys/syscall.h> 44 #include <sys/vnode.h> 45 #include <sys/systm.h> 46 #include <machine/md_var.h> 47 48 #include <vm/vm.h> 49 #include <vm/vm_param.h> 50 #include <vm/vm_prot.h> 51 #include <sys/lock.h> 52 #include <vm/pmap.h> 53 #include <vm/vm_map.h> 54 #include <vm/vm_object.h> 55 #include <sys/user.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 }; 76 77 static int 78 exec_aout_imgact(imgp) 79 struct image_params *imgp; 80 { 81 const struct exec *a_out = (const struct exec *) imgp->image_header; 82 struct vmspace *vmspace; 83 struct vnode *vp; 84 vm_map_t map; 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 /* Pass PS_STRINGS for BSD/OS binaries only. */ 122 if (N_GETMID(*a_out) == MID_ZERO) 123 imgp->ps_strings = PS_STRINGS; 124 break; 125 default: 126 /* NetBSD compatibility */ 127 switch ((int)(ntohl(a_out->a_magic) & 0xffff)) { 128 case ZMAGIC: 129 case QMAGIC: 130 virtual_offset = PAGE_SIZE; 131 file_offset = 0; 132 break; 133 default: 134 return (-1); 135 } 136 } 137 138 bss_size = roundup(a_out->a_bss, PAGE_SIZE); 139 140 /* 141 * Check various fields in header for validity/bounds. 142 */ 143 if (/* entry point must lay with text region */ 144 a_out->a_entry < virtual_offset || 145 a_out->a_entry >= virtual_offset + a_out->a_text || 146 147 /* text and data size must each be page rounded */ 148 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK) 149 return (-1); 150 151 /* text + data can't exceed file size */ 152 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 153 return (EFAULT); 154 155 /* 156 * text/data/bss must not exceed limits 157 */ 158 if (/* text can't exceed maximum text size */ 159 a_out->a_text > MAXTSIZ || 160 161 /* data + bss can't exceed rlimit */ 162 a_out->a_data + bss_size > 163 imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur) 164 return (ENOMEM); 165 166 /* copy in arguments and/or environment from old process */ 167 error = exec_extract_strings(imgp); 168 if (error) 169 return (error); 170 171 /* 172 * Destroy old process VM and create a new one (with a new stack) 173 */ 174 exec_new_vmspace(imgp); 175 176 /* 177 * The vm space can be changed by exec_new_vmspace 178 */ 179 vmspace = imgp->proc->p_vmspace; 180 181 vp = imgp->vp; 182 map = &vmspace->vm_map; 183 vm_map_lock(map); 184 object = vp->v_object; 185 vm_object_reference(object); 186 187 text_end = virtual_offset + a_out->a_text; 188 error = vm_map_insert(map, object, 189 file_offset, 190 virtual_offset, text_end, 191 VM_PROT_READ | VM_PROT_EXECUTE, VM_PROT_ALL, 192 MAP_COPY_ON_WRITE | MAP_PREFAULT); 193 if (error) { 194 vm_map_unlock(map); 195 return (error); 196 } 197 data_end = text_end + a_out->a_data; 198 if (a_out->a_data) { 199 vm_object_reference(object); 200 error = vm_map_insert(map, object, 201 file_offset + a_out->a_text, 202 text_end, data_end, 203 VM_PROT_ALL, VM_PROT_ALL, 204 MAP_COPY_ON_WRITE | MAP_PREFAULT); 205 if (error) { 206 vm_map_unlock(map); 207 return (error); 208 } 209 } 210 211 if (bss_size) { 212 error = vm_map_insert(map, NULL, 0, 213 data_end, data_end + bss_size, 214 VM_PROT_ALL, VM_PROT_ALL, 0); 215 if (error) { 216 vm_map_unlock(map); 217 return (error); 218 } 219 } 220 vm_map_unlock(map); 221 222 /* Fill in process VM information */ 223 vmspace->vm_tsize = a_out->a_text >> PAGE_SHIFT; 224 vmspace->vm_dsize = (a_out->a_data + bss_size) >> PAGE_SHIFT; 225 vmspace->vm_taddr = (caddr_t) (uintptr_t) virtual_offset; 226 vmspace->vm_daddr = (caddr_t) (uintptr_t) 227 (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 = &aout_sysvec; 234 235 /* Indicate that this file should not be modified */ 236 imgp->vp->v_flag |= VTEXT; 237 238 return (0); 239 } 240 241 /* 242 * Dump core, into a file named as described in the comments for 243 * expand_name(), unless the process was setuid/setgid. 244 */ 245 int 246 aout_coredump(p, vp, limit) 247 register struct proc *p; 248 register struct vnode *vp; 249 off_t limit; 250 { 251 register struct ucred *cred = p->p_cred->pc_ucred; 252 register struct vmspace *vm = p->p_vmspace; 253 int error; 254 255 if (ctob(UPAGES + vm->vm_dsize + vm->vm_ssize) >= limit) 256 return (EFAULT); 257 bcopy(p, &p->p_addr->u_kproc.kp_proc, sizeof(struct proc)); 258 fill_eproc(p, &p->p_addr->u_kproc.kp_eproc); 259 error = cpu_coredump(p, vp, cred); 260 if (error == 0) 261 error = vn_rdwr(UIO_WRITE, vp, vm->vm_daddr, 262 (int)ctob(vm->vm_dsize), (off_t)ctob(UPAGES), UIO_USERSPACE, 263 IO_NODELOCKED|IO_UNIT, cred, (int *) NULL, p); 264 if (error == 0) 265 error = vn_rdwr(UIO_WRITE, vp, 266 (caddr_t) trunc_page(USRSTACK - ctob(vm->vm_ssize)), 267 round_page(ctob(vm->vm_ssize)), 268 (off_t)ctob(UPAGES) + ctob(vm->vm_dsize), UIO_USERSPACE, 269 IO_NODELOCKED|IO_UNIT, cred, (int *) NULL, p); 270 return (error); 271 } 272 273 /* 274 * Tell kern_execve.c about it, with a little help from the linker. 275 */ 276 static struct execsw aout_execsw = { exec_aout_imgact, "a.out" }; 277 EXEC_SET(aout, aout_execsw); 278