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/limits.h> 36 #include <sys/lock.h> 37 #include <sys/malloc.h> 38 #include <sys/mutex.h> 39 #include <sys/proc.h> 40 #include <sys/racct.h> 41 #include <sys/resourcevar.h> 42 #include <sys/signalvar.h> 43 #include <sys/syscall.h> 44 #include <sys/sysent.h> 45 #include <sys/systm.h> 46 #include <sys/vnode.h> 47 48 #include <machine/frame.h> 49 #include <machine/md_var.h> 50 51 #include <vm/vm.h> 52 #include <vm/pmap.h> 53 #include <vm/vm_map.h> 54 #include <vm/vm_object.h> 55 #include <vm/vm_param.h> 56 57 #ifdef __amd64__ 58 #include <compat/freebsd32/freebsd32_signal.h> 59 #include <compat/freebsd32/freebsd32_util.h> 60 #include <compat/freebsd32/freebsd32_proto.h> 61 #include <compat/freebsd32/freebsd32_syscall.h> 62 #include <compat/ia32/ia32_signal.h> 63 #endif 64 65 static int exec_aout_imgact(struct image_params *imgp); 66 static int aout_fixup(register_t **stack_base, struct image_params *imgp); 67 68 #if defined(__i386__) 69 struct sysentvec aout_sysvec = { 70 .sv_size = SYS_MAXSYSCALL, 71 .sv_table = sysent, 72 .sv_mask = 0, 73 .sv_errsize = 0, 74 .sv_errtbl = NULL, 75 .sv_transtrap = NULL, 76 .sv_fixup = aout_fixup, 77 .sv_sendsig = sendsig, 78 .sv_sigcode = sigcode, 79 .sv_szsigcode = &szsigcode, 80 .sv_name = "FreeBSD a.out", 81 .sv_coredump = NULL, 82 .sv_imgact_try = NULL, 83 .sv_minsigstksz = MINSIGSTKSZ, 84 .sv_pagesize = PAGE_SIZE, 85 .sv_minuser = VM_MIN_ADDRESS, 86 .sv_maxuser = VM_MAXUSER_ADDRESS, 87 .sv_usrstack = USRSTACK, 88 .sv_psstrings = PS_STRINGS, 89 .sv_stackprot = VM_PROT_ALL, 90 .sv_copyout_strings = exec_copyout_strings, 91 .sv_setregs = exec_setregs, 92 .sv_fixlimit = NULL, 93 .sv_maxssiz = NULL, 94 .sv_flags = SV_ABI_FREEBSD | SV_AOUT | SV_IA32 | SV_ILP32, 95 .sv_set_syscall_retval = cpu_set_syscall_retval, 96 .sv_fetch_syscall_args = cpu_fetch_syscall_args, 97 .sv_syscallnames = syscallnames, 98 .sv_schedtail = NULL, 99 .sv_thread_detach = NULL, 100 }; 101 102 #elif defined(__amd64__) 103 104 #define AOUT32_USRSTACK 0xbfc00000 105 #define AOUT32_PS_STRINGS \ 106 (AOUT32_USRSTACK - sizeof(struct freebsd32_ps_strings)) 107 #define AOUT32_MINUSER FREEBSD32_MINUSER 108 109 extern const char *freebsd32_syscallnames[]; 110 extern u_long ia32_maxssiz; 111 112 struct sysentvec aout_sysvec = { 113 .sv_size = FREEBSD32_SYS_MAXSYSCALL, 114 .sv_table = freebsd32_sysent, 115 .sv_mask = 0, 116 .sv_errsize = 0, 117 .sv_errtbl = NULL, 118 .sv_transtrap = NULL, 119 .sv_fixup = aout_fixup, 120 .sv_sendsig = ia32_sendsig, 121 .sv_sigcode = ia32_sigcode, 122 .sv_szsigcode = &sz_ia32_sigcode, 123 .sv_name = "FreeBSD a.out", 124 .sv_coredump = NULL, 125 .sv_imgact_try = NULL, 126 .sv_minsigstksz = MINSIGSTKSZ, 127 .sv_pagesize = IA32_PAGE_SIZE, 128 .sv_minuser = AOUT32_MINUSER, 129 .sv_maxuser = AOUT32_USRSTACK, 130 .sv_usrstack = AOUT32_USRSTACK, 131 .sv_psstrings = AOUT32_PS_STRINGS, 132 .sv_stackprot = VM_PROT_ALL, 133 .sv_copyout_strings = freebsd32_copyout_strings, 134 .sv_setregs = ia32_setregs, 135 .sv_fixlimit = ia32_fixlimit, 136 .sv_maxssiz = &ia32_maxssiz, 137 .sv_flags = SV_ABI_FREEBSD | SV_AOUT | SV_IA32 | SV_ILP32, 138 .sv_set_syscall_retval = ia32_set_syscall_retval, 139 .sv_fetch_syscall_args = ia32_fetch_syscall_args, 140 .sv_syscallnames = freebsd32_syscallnames, 141 }; 142 #else 143 #error "Port me" 144 #endif 145 146 static int 147 aout_fixup(register_t **stack_base, struct image_params *imgp) 148 { 149 150 *(char **)stack_base -= sizeof(uint32_t); 151 return (suword32(*stack_base, imgp->args->argc)); 152 } 153 154 static int 155 exec_aout_imgact(struct image_params *imgp) 156 { 157 const struct exec *a_out = (const struct exec *) imgp->image_header; 158 struct vmspace *vmspace; 159 vm_map_t map; 160 vm_object_t object; 161 vm_offset_t text_end, data_end; 162 unsigned long virtual_offset; 163 unsigned long file_offset; 164 unsigned long bss_size; 165 int error; 166 167 /* 168 * Linux and *BSD binaries look very much alike, 169 * only the machine id is different: 170 * 0x64 for Linux, 0x86 for *BSD, 0x00 for BSDI. 171 * NetBSD is in network byte order.. ugh. 172 */ 173 if (((a_out->a_midmag >> 16) & 0xff) != 0x86 && 174 ((a_out->a_midmag >> 16) & 0xff) != 0 && 175 ((((int)ntohl(a_out->a_midmag)) >> 16) & 0xff) != 0x86) 176 return -1; 177 178 /* 179 * Set file/virtual offset based on a.out variant. 180 * We do two cases: host byte order and network byte order 181 * (for NetBSD compatibility) 182 */ 183 switch ((int)(a_out->a_midmag & 0xffff)) { 184 case ZMAGIC: 185 virtual_offset = 0; 186 if (a_out->a_text) { 187 file_offset = PAGE_SIZE; 188 } else { 189 /* Bill's "screwball mode" */ 190 file_offset = 0; 191 } 192 break; 193 case QMAGIC: 194 virtual_offset = PAGE_SIZE; 195 file_offset = 0; 196 /* Pass PS_STRINGS for BSD/OS binaries only. */ 197 if (N_GETMID(*a_out) == MID_ZERO) 198 imgp->ps_strings = aout_sysvec.sv_psstrings; 199 break; 200 default: 201 /* NetBSD compatibility */ 202 switch ((int)(ntohl(a_out->a_midmag) & 0xffff)) { 203 case ZMAGIC: 204 case QMAGIC: 205 virtual_offset = PAGE_SIZE; 206 file_offset = 0; 207 break; 208 default: 209 return (-1); 210 } 211 } 212 213 bss_size = roundup(a_out->a_bss, PAGE_SIZE); 214 215 /* 216 * Check various fields in header for validity/bounds. 217 */ 218 if (/* entry point must lay with text region */ 219 a_out->a_entry < virtual_offset || 220 a_out->a_entry >= virtual_offset + a_out->a_text || 221 222 /* text and data size must each be page rounded */ 223 a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK 224 225 #ifdef __amd64__ 226 || 227 /* overflows */ 228 virtual_offset + a_out->a_text + a_out->a_data + bss_size > UINT_MAX 229 #endif 230 ) 231 return (-1); 232 233 /* text + data can't exceed file size */ 234 if (a_out->a_data + a_out->a_text > imgp->attr->va_size) 235 return (EFAULT); 236 237 /* 238 * text/data/bss must not exceed limits 239 */ 240 PROC_LOCK(imgp->proc); 241 if (/* text can't exceed maximum text size */ 242 a_out->a_text > maxtsiz || 243 244 /* data + bss can't exceed rlimit */ 245 a_out->a_data + bss_size > lim_cur_proc(imgp->proc, RLIMIT_DATA) || 246 racct_set(imgp->proc, RACCT_DATA, a_out->a_data + bss_size) != 0) { 247 PROC_UNLOCK(imgp->proc); 248 return (ENOMEM); 249 } 250 PROC_UNLOCK(imgp->proc); 251 252 /* 253 * Avoid a possible deadlock if the current address space is destroyed 254 * and that address space maps the locked vnode. In the common case, 255 * the locked vnode's v_usecount is decremented but remains greater 256 * than zero. Consequently, the vnode lock is not needed by vrele(). 257 * However, in cases where the vnode lock is external, such as nullfs, 258 * v_usecount may become zero. 259 */ 260 VOP_UNLOCK(imgp->vp, 0); 261 262 /* 263 * Destroy old process VM and create a new one (with a new stack) 264 */ 265 error = exec_new_vmspace(imgp, &aout_sysvec); 266 267 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); 268 if (error) 269 return (error); 270 271 /* 272 * The vm space can be changed by exec_new_vmspace 273 */ 274 vmspace = imgp->proc->p_vmspace; 275 276 object = imgp->object; 277 map = &vmspace->vm_map; 278 vm_map_lock(map); 279 vm_object_reference(object); 280 281 text_end = virtual_offset + a_out->a_text; 282 error = vm_map_insert(map, object, 283 file_offset, 284 virtual_offset, text_end, 285 VM_PROT_READ | VM_PROT_EXECUTE, VM_PROT_ALL, 286 MAP_COPY_ON_WRITE | MAP_PREFAULT); 287 if (error) { 288 vm_map_unlock(map); 289 vm_object_deallocate(object); 290 return (error); 291 } 292 data_end = text_end + a_out->a_data; 293 if (a_out->a_data) { 294 vm_object_reference(object); 295 error = vm_map_insert(map, object, 296 file_offset + a_out->a_text, 297 text_end, data_end, 298 VM_PROT_ALL, VM_PROT_ALL, 299 MAP_COPY_ON_WRITE | MAP_PREFAULT); 300 if (error) { 301 vm_map_unlock(map); 302 vm_object_deallocate(object); 303 return (error); 304 } 305 } 306 307 if (bss_size) { 308 error = vm_map_insert(map, NULL, 0, 309 data_end, data_end + bss_size, 310 VM_PROT_ALL, VM_PROT_ALL, 0); 311 if (error) { 312 vm_map_unlock(map); 313 return (error); 314 } 315 } 316 vm_map_unlock(map); 317 318 /* Fill in process VM information */ 319 vmspace->vm_tsize = a_out->a_text >> PAGE_SHIFT; 320 vmspace->vm_dsize = (a_out->a_data + bss_size) >> PAGE_SHIFT; 321 vmspace->vm_taddr = (caddr_t) (uintptr_t) virtual_offset; 322 vmspace->vm_daddr = (caddr_t) (uintptr_t) 323 (virtual_offset + a_out->a_text); 324 325 /* Fill in image_params */ 326 imgp->interpreted = 0; 327 imgp->entry_addr = a_out->a_entry; 328 329 imgp->proc->p_sysent = &aout_sysvec; 330 331 return (0); 332 } 333 334 /* 335 * Tell kern_execve.c about it, with a little help from the linker. 336 */ 337 static struct execsw aout_execsw = { exec_aout_imgact, "a.out" }; 338 EXEC_SET(aout, aout_execsw); 339