kernel panic caused by script(1)

[Emiel Kollof <coolvibe@xxxxxxxxxxxxxxxx>]

See attached crashdump. Portupgrade seems to reliably trigger the panic for
me. If you want, I can upload vmcore and kernel.debug to leaf.

Cheers,
Emiel
-- 
C, n.:
        A programming language that is sort of like Pascal except more
like assembly except that it isn't very much like either one, or
anything else.  It is either the best language available to the art
today, or it isn't.
                -- Ray Simard

1 cpu [ff800000,32768]
IdlePTD at phsyical address 0x006c2000
PCB @003cbfe0 EIP=c01d3ec2 ESP=d03a3764 EBP=d03a3770
initial pcb at physical address 0x003cbfe0
panicstr: page fault
panic messages:
---
Fatal trap 12: page fault while in kernel mode
fault virtual address	= 0x38
fault code		= supervisor write, page not present
instruction pointer	= 0x8:0xc01c3ecc
stack pointer	        = 0x10:0xd03a3970
frame pointer	        = 0x10:0xd03a3974
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, def32 1, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= 1122 (script)
current thread          = pri 6 
interrupt mask		= none
trap number		= 12
panic: page fault

syncing disks... 3 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 


Fatal trap 12: page fault while in kernel mode
fault virtual address	= 0x0
fault code		= supervisor read, page not present
instruction pointer	= 0x8:0xc01d3bcb
stack pointer	        = 0x10:0xd03a3874
frame pointer	        = 0x10:0xd03a3890
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, def32 1, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= 1122 (script)
current thread          = pri 6 
interrupt mask		= none
trap number		= 12
panic: page fault
Uptime: 14m19s

dumping to dev #ad/0x30001, offset 1048608
dump ata0: resetting devices .. done
511 510 509 508 507 506 505 504 503 502 501 500 499 498 497 496 495 494 493 492 491 490 489 488 487 486 485 484 483 482 481 480 479 478 477 476 475 474 473 472 471 470 469 468 467 466 465 464 463 462 461 460 459 458 457 456 455 454 453 452 451 450 449 448 447 446 445 444 443 442 441 440 439 438 437 436 435 434 433 432 431 430 429 428 427 426 425 424 423 422 421 420 419 418 417 416 415 414 413 412 411 410 409 408 407 406 405 404 403 402 401 400 399 398 397 396 395 394 393 392 391 390 389 388 387
 386 385 384 383 382 381 380 379 378 377 376 375 374 373 372 371 370 369 368 367 366 365 364 363 362 361 360 359 358 357 356 355 354 353 352 351 350 349 348 [CTRL-C to abort] 347 346 345 344 343 342 341 340 339 338 337 336 335 334 333 332 331 330 329 328 327 326 325 324 323 322 321 320 319 318 317 316 315 314 313 312 311 310 309 308 307 306 305 304 303 302 301 300 299 298 297 296 295 294 293 292 291 290 289 288 287 286 285 284 283 282 281 280 279 278 277 276 275 274 273 272 271 270 269 268 267 
266 265 264 263 262 261 260 259 258 257 256 255 254 253 252 251 250 249 248 247 246 245 244 243 242 241 240 239 238 237 236 235 234 233 232 231 230 229 228 227 226 225 224 223 222 221 220 219 218 217 216 215 214 213 212 211 210 209 208 207 206 205 204 203 202 201 200 199 198 197 196 195 194 193 192 191 190 189 188 187 186 185 184 183 182 181 180 179 178 177 176 175 174 173 172 171 170 169 168 167 166 165 164 163 162 161 160 159 158 157 156 155 154 153 152 151 150 149 148 147 146 145 144 143 142
 141 140 139 138 137 136 135 134 133 132 131 130 129 128 127 126 125 124 123 122 121 120 119 118 117 116 115 114 113 112 111 110 109 108 107 106 105 104 103 102 101 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 
---
#0  dumpsys () at /usr/src/sys/kern/kern_shutdown.c:500
500		if (dumping++) {
#0  dumpsys () at /usr/src/sys/kern/kern_shutdown.c:500
#1  0xc01d3cb7 in boot (howto=260) at /usr/src/sys/kern/kern_shutdown.c:333
#2  0xc01d40e8 in poweroff_wait (junk=0xc037f8ea, howto=-1070075122)
    at /usr/src/sys/kern/kern_shutdown.c:612
#3  0xc03139a9 in trap_fatal (frame=0xd03a3834, eva=0)
    at /usr/src/sys/i386/i386/trap.c:1092
#4  0xc03135ad in trap_pfault (frame=0xd03a3834, usermode=0, eva=0)
    at /usr/src/sys/i386/i386/trap.c:981
#5  0xc03132a4 in trap (frame={tf_fs = -801505256, tf_es = -1071906800, 
      tf_ds = -801505264, tf_edi = 0, tf_esi = 1, tf_ebp = -801490800, 
      tf_isp = -801490848, tf_ebx = -1046352372, tf_edx = 0, 
      tf_ecx = -924859808, tf_eax = 0, tf_trapno = 12, tf_err = 0, 
      tf_eip = -1071825973, tf_cs = 8, tf_eflags = 66118, 
      tf_esp = -1070073622, tf_ss = 256}) at /usr/src/sys/i386/i386/trap.c:561
#6  0xc01d3bcb in boot (howto=256) at /usr/src/sys/kern/kern_shutdown.c:292
#7  0xc01d40e8 in poweroff_wait (junk=0xc037f8ea, howto=-1070075122)
    at /usr/src/sys/kern/kern_shutdown.c:612
#8  0xc03139a9 in trap_fatal (frame=0xd03a3930, eva=56)
    at /usr/src/sys/i386/i386/trap.c:1092
#9  0xc03135ad in trap_pfault (frame=0xd03a3930, usermode=0, eva=56)
    at /usr/src/sys/i386/i386/trap.c:981
#10 0xc03132a4 in trap (frame={tf_fs = -1046609896, tf_es = -801505264, 
      tf_ds = -801505264, tf_edi = 0, tf_esi = -803081728, 
      tf_ebp = -801490572, tf_isp = -801490596, tf_ebx = 0, 
      tf_edx = -801490472, tf_ecx = -924859624, tf_eax = -924859808, 
      tf_trapno = 12, tf_err = 2, tf_eip = -1071890740, tf_cs = 8, 
      tf_eflags = 66067, tf_esp = -827750720, tf_ss = -801490548})
    at /usr/src/sys/i386/i386/trap.c:561
#11 0xc01c3ecc in reference_dev (dev=0x0) at /usr/src/sys/kern/kern_conf.c:379
#12 0xc021579b in spec_close (ap=0xd03a39d8)
    at /usr/src/sys/vfs/specfs/spec_vnops.c:578
#13 0xc02bb61e in ufsspec_close (ap=0xd03a39d8)
    at /usr/src/sys/vfs/ufs/ufs_vnops.c:1785
#14 0xc02bbc71 in ufs_vnoperatespec (ap=0xd03a39d8)
    at /usr/src/sys/vfs/ufs/ufs_vnops.c:2300
#15 0xc0210fbe in vn_close (vp=0xcea986c0, flags=3, td=0xc8dfc260)
    at vnode_if.h:289
#16 0xc0211978 in vn_closefile (fp=0xd006adf8, td=0xc8dfc260)
    at /usr/src/sys/kern/vfs_vnops.c:696
#17 0xc01c644f in fdrop (fp=0xd006adf8, td=0xc8dfc260)
    at /usr/src/sys/sys/file2.h:125
#18 0xc01c6397 in closef (fp=0xd006adf8, td=0xc8dfc260)
    at /usr/src/sys/kern/kern_descrip.c:1444
#19 0xc01c5e68 in fdfree (p=0xd021f200)
    at /usr/src/sys/kern/kern_descrip.c:1190
#20 0xc01c9b15 in exit1 (rv=0) at /usr/src/sys/kern/kern_exit.c:188
#21 0xc01c9925 in sys_exit (uap=0xd03a3c40)
    at /usr/src/sys/kern/kern_exit.c:103
#22 0xc0313cc6 in syscall2 (frame={tf_fs = 47, tf_es = 47, tf_ds = 47, 
      tf_edi = 1, tf_esi = -1077938360, tf_ebp = -1077939648, 
      tf_isp = -801489548, tf_ebx = 672090348, tf_edx = 672089792, 
      tf_ecx = 134537216, tf_eax = 1, tf_trapno = 12, tf_err = 2, 
      tf_eip = 671775392, tf_cs = 31, tf_eflags = 643, tf_esp = -1077939692, 
      tf_ss = 47}) at /usr/src/sys/i386/i386/trap.c:1297
#23 0xc03032aa in Xint0x80_syscall ()
#24 0x804918b in ?? ()
#25 0x8048faa in ?? ()
#26 0x8048aae in ?? ()
#11 0xc01c3ecc in reference_dev (dev=0x0) at /usr/src/sys/kern/kern_conf.c:379
379		if (dev != NODEV) {