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