NOFORK_NOEXEC.lst

   1 Why an applet can't be NOFORK or NOEXEC?
   2
   3 Why can't be NOFORK:
   4 interactive: may wait for user input, ^C has to work
   5 spawner: "tool PROG ARGS" which changes program's environment - must fork
   6 changes state: e.g. environment, signal handlers
   7 alloc+xfunc: xmalloc, then xfunc - leaks memory if xfunc dies
   8 open+xfunc: opens fd, then calls xfunc - fd is leaked if xfunc dies
   9 runner: sometimes may run for long(ish) time, and/or works with network:
  10         ^C has to work (cat BIGFILE, chmod -R, ftpget, nc)
  11
  12 "runners" can become eligible after shell is taught ^C to interrupt NOFORKs!
  13
  14 Why can't be NOEXEC:
  15 suid: runs under different uid - must fork+exec
  16
  17 Why shouldn't be NOFORK/NOEXEC:
  18 complex: no immediately obvious reason why NOFORK wouldn't work,
  19         but does some non-obvoius operations (example: fuser, lsof, losetup);
  20         nested xmallocs (typical in complex code) is a problem for NOFORK
  21 rare: not used often enough to bother optimizing (example: poweroff)
  22 longterm: often runs for a long time (many seconds), execing would make
  23         memory footprint smaller
  24 daemon: runs indefinitely
  25
  26 [ - NOFORK
  27 [[ - NOFORK
  28 acpid - daemon
  29 add-shell
  30 addgroup
  31 adduser
  32 adjtimex
  33 ar - runner
  34 arch - NOFORK
  35 arp
  36 arping - runner
  37 ash - interactive
  38 awk - noexec. runner
  39 base64 - runner
  40 basename - NOFORK
  41 beep
  42 blkdiscard
  43 blkid
  44 blockdev
  45 bootchartd - daemon
  46 brctl
  47 bunzip2 - runner
  48 busybox
  49 bzcat - runner
  50 bzip2 - runner
  51 cal - runner: cal -n9999
  52 cat - runner
  53 chat
  54 chattr - runner
  55 chgrp - noexec. runner
  56 chmod - noexec. runner
  57 chown - noexec. runner
  58 chpasswd - runner (list of "user:password"s from stdin)
  59 chpst - spawner
  60 chroot - spawner
  61 chrt - spawner
  62 chvt
  63 cksum - noexec. runner
  64 clear - NOFORK
  65 cmp - runner
  66 comm - runner
  67 conspy - interactive
  68 cp - noexec. runner
  69 cpio - runner
  70 crond - daemon
  71 crontab
  72 cryptpw
  73 cttyhack - spawner
  74 cut - noexec. runner
  75 date - noexec. nofork candidate(needs to stop messing up env, free xasprintf result, not use xfuncs after xasprintf)
  76 dc - runner (eats stdin if no params)
  77 dd - noexec. runner
  78 deallocvt
  79 delgroup
  80 deluser
  81 depmod
  82 devmem - runner, complex (access to device memory may hang)
  83 df - complex (nested allocs)
  84 dhcprelay - daemon
  85 diff - runner
  86 dirname - NOFORK
  87 dmesg - runner
  88 dnsd - daemon
  89 dnsdomainname - DNS resolution may trigger, need ^C
  90 dos2unix - noexec. runner
  91 dpkg - runner
  92 du - runner
  93 dumpkmap
  94 dumpleases
  95 echo - NOFORK
  96 ed - interactive
  97 egrep - runner
  98 eject
  99 env - noexec. changes state (env)
 100 envdir - spawner
 101 envuidgid - spawner
 102 expand - runner
 103 expr - complex (nested allocs)
 104 factor - runner (eats stdin if no params)
 105 fakeidentd - daemon
 106 false - NOFORK
 107 fatattr - complex (xopen+xioctl can leak fd)
 108 fbset
 109 fbsplash - runner, interactive
 110 fdflush
 111 fdformat - runner
 112 fdisk - interactive
 113 fgconsole
 114 fgrep - runner
 115 find - noexec. runner
 116 findfs - suid
 117 flash_eraseall
 118 flash_lock
 119 flash_unlock
 120 flashcp
 121 flock
 122 fold - noexec. runner
 123 free - nofork candidate(struct globals, needs to close /proc/meminfo fd)
 124 freeramdisk
 125 fsck - interactive
 126 fsck.minix
 127 fsfreeze
 128 fstrim
 129 fsync - NOFORK
 130 ftpd - daemon
 131 ftpget - runner
 132 ftpput - runner
 133 fuser - complex
 134 getopt - noexec. complex (many allocs)
 135 getty - interactive
 136 grep - runner
 137 groups - noexec
 138 gunzip - runner
 139 gzip - runner
 140 halt - rare
 141 hd - noexec. runner
 142 hdparm - complex, rare
 143 head - noexec. runner
 144 hexdump - noexec. runner
 145 hostid - NOFORK
 146 hostname - DNS resolution may trigger, need ^C
 147 httpd - daemon
 148 hush - interactive
 149 hwclock
 150 i2cdetect
 151 i2cdump
 152 i2cget
 153 i2cset
 154 id - noexec
 155 ifconfig
 156 ifenslave
 157 ifplugd - daemon
 158 inetd - daemon
 159 init - daemon
 160 inotifyd - daemon
 161 insmod - noexec
 162 install - runner
 163 ionice - spawner
 164 iostat - runner
 165 ip - noexec candidate
 166 ipaddr - noexec candidate
 167 ipcalc - noexec candidate
 168 ipcrm - noexec candidate
 169 ipcs - noexec candidate
 170 iplink - noexec candidate
 171 ipneigh - noexec candidate
 172 iproute - noexec candidate
 173 iprule - noexec candidate
 174 iptunnel - noexec candidate
 175 kbd_mode
 176 kill - NOFORK
 177 killall - NOFORK
 178 killall5 - NOFORK
 179 klogd - daemon
 180 last - runner (I've got 1300 lines of output when tried it)
 181 less - interactive
 182 link - NOFORK
 183 linux32 - spawner
 184 linux64 - spawner
 185 linuxrc - daemon
 186 ln - noexec
 187 loadfont
 188 loadkmap
 189 logger - runner
 190 login - suid, interactive
 191 logname - NOFORK
 192 losetup - complex
 193 lpd - daemon
 194 lpq - runner
 195 lpr - runner
 196 ls - noexec. runner
 197 lsattr
 198 lsmod - noexec
 199 lsof - complex
 200 lspci
 201 lsscsi
 202 lsusb
 203 lzcat - runner
 204 lzma - runner
 205 lzop - runner
 206 lzopcat - runner
 207 makedevs
 208 makemime - runner
 209 man - spawner, interactive
 210 md5sum - noexec. runner
 211 mdev - daemon
 212 mesg
 213 microcom - interactive, complex
 214 mkdir - NOFORK
 215 mkdosfs
 216 mke2fs
 217 mkfifo - noexec
 218 mkfs.ext2
 219 mkfs.minix
 220 mkfs.vfat
 221 mknod - noexec
 222 mkpasswd
 223 mkswap
 224 mktemp
 225 modinfo - noexec
 226 modprobe - noexec
 227 more - interactive
 228 mount - suid
 229 mountpoint
 230 mpstat
 231 mt
 232 mv - runner (can be noexec?)
 233 nameif
 234 nbd-client
 235 nc - runner
 236 netstat - runner with -c
 237 nice - spawner
 238 nl - runner
 239 nmeter - runner
 240 nohup - spawner
 241 nproc - NOFORK
 242 ntpd - daemon
 243 od - runner
 244 openvt - spawner
 245 partprobe
 246 passwd - suid
 247 paste - noexec. runner
 248 patch
 249 pgrep - nofork candidate(xregcomp, procps_scan - are they ok?)
 250 pidof - nofork candidate(uses find_pid_by_name, is that ok?)
 251 ping - suid, runner
 252 ping6 - suid, runner
 253 pipe_progress
 254 pivot_root
 255 pkill - nofork candidate(xregcomp, procps_scan - are they ok?)
 256 pmap
 257 popmaildir - runner
 258 poweroff - rare
 259 powertop - interactive, longterm
 260 printenv - NOFORK
 261 printf - NOFORK
 262 ps - noexec candidate
 263 pscan - longterm
 264 pstree
 265 pwd - NOFORK
 266 pwdx - NOFORK
 267 raidautorun
 268 rdate
 269 rdev
 270 readlink - NOFORK
 271 readprofile
 272 realpath - NOFORK
 273 reboot - rare
 274 reformime - runner
 275 remove-shell
 276 renice - nofork candidate(uses getpwnam, is that ok?)
 277 reset - spawner (execs "stty")
 278 resize - noexec. changes state (signal handlers)
 279 rev - runner
 280 rm - noexec. rm -i interactive
 281 rmdir - NOFORK
 282 rmmod - noexec
 283 route
 284 rpm - runner
 285 rpm2cpio - runner
 286 rtcwake - complex, rare
 287 run-parts
 288 runlevel
 289 runsv - daemon
 290 runsvdir - daemon
 291 rx - runner
 292 script
 293 scriptreplay
 294 sed - runner
 295 sendmail - runner
 296 seq - noexec. runner
 297 setarch - spawner
 298 setconsole
 299 setfont
 300 setkeycodes
 301 setlogcons
 302 setpriv - spawner
 303 setserial
 304 setsid - spawner
 305 setuidgid
 306 sh - interactive
 307 sha1sum - noexec. runner
 308 sha256sum - noexec. runner
 309 sha3sum - noexec. runner
 310 sha512sum - noexec. runner
 311 showkey - interactive
 312 shred - runner
 313 shuf - noexec. runner
 314 slattach
 315 sleep - runner
 316 smemcap - runner
 317 softlimit - spawner
 318 sort - noexec. runner
 319 split - runner
 320 ssl_client - network
 321 start-stop-daemon
 322 stat - nofork candidate(needs fewer allocs)
 323 strings - runner
 324 stty
 325 su - suid, spawner
 326 sulogin - spawner
 327 sum - runner
 328 sv
 329 svc
 330 svlogd - daemon
 331 swapoff - rare
 332 swapon - rare
 333 switch_root - spawner, rare, changes state
 334 sync - NOFORK
 335 sysctl
 336 syslogd - daemon
 337 tac - noexec. runner
 338 tail - runner
 339 tar - runner
 340 taskset - spawner
 341 tcpsvd - daemon
 342 tee - runner
 343 telnet - interactive
 344 telnetd - daemon
 345 test - NOFORK
 346 tftp - runner
 347 tftpd - daemon
 348 time - spawner, changes state (signals)
 349 timeout - spawner, changes state (signals)
 350 top - interactive, longterm
 351 touch - NOFORK
 352 tr - runner
 353 traceroute - suid, runner
 354 traceroute6 - suid, runner
 355 true - NOFORK
 356 truncate - NOFORK
 357 tty - NOFORK
 358 ttysize - NOFORK
 359 tunctl
 360 tune2fs
 361 ubiattach
 362 ubidetach
 363 ubimkvol
 364 ubirename
 365 ubirmvol
 366 ubirsvol
 367 ubiupdatevol
 368 udhcpc - daemon
 369 udhcpd - daemon
 370 udpsvd - daemon
 371 uevent - daemon
 372 umount
 373 uname - NOFORK
 374 uncompress - runner
 375 unexpand - runner
 376 uniq - runner
 377 unix2dos - noexec. runner
 378 unlink - NOFORK
 379 unlzma - runner
 380 unlzop - runner
 381 unxz - runner
 382 unzip - runner
 383 uptime - nofork candidate(is getutxent ok?)
 384 users - nofork candidate(is getutxent ok?)
 385 usleep - NOFORK
 386 uudecode - runner
 387 uuencode - runner
 388 vconfig
 389 vi - interactive
 390 vlock - suid
 391 volname - runner
 392 w
 393 wall - suid
 394 watch - runner
 395 watchdog - daemon
 396 wc - runner
 397 wget - runner
 398 which - NOFORK
 399 who
 400 whoami - NOFORK
 401 whois
 402 xargs - noexec. spawner
 403 xxd - noexec. runner
 404 xz - runner
 405 xzcat - runner
 406 yes - noexec. runner
 407 zcat - runner
 408 zcip - daemon