Changeset 3232 in MondoRescue for branches/3.2/mindi-busybox/docs/nofork_noexec.txt

Timestamp:

Jan 1, 2014, 12:47:38 AM (10 years ago)

Author:

Bruno Cornec

Message:

• Update mindi-busybox to 1.21.1

File:

• branches/3.2/mindi-busybox/docs/nofork_noexec.txt (modified) (3 diffs)

branches/3.2/mindi-busybox/docs/nofork_noexec.txt

@@ -45 +45 @@
 
 NOFORK applet should work correctly if another applet simply runs
-<applet>_main(argc,argv) and then continues with its business (xargs,
-find, shells can do it). This poses much more serious limitations
-on what applet can/cannot do:
+<applet>_main(argc,argv) and then continues with its business.
+xargs, find, shells do it (grep for "spawn_and_wait" and
+"run_nofork_applet" to find more users).
+
+This poses much more serious limitations on what applet can do:
 
 * all NOEXEC limitations apply.
@@ -57 +59 @@
   - fflush_stdout_and_exit(n) is ok to use.
 * do not use shared global data, or save/restore shared global data
-  prior to returning. (e.g. bb_common_bufsiz1 is off-limits).
+  (e.g. bb_common_bufsiz1) prior to returning.
   - getopt32() is ok to use. You do not need to save/restore option_mask32,
     it is already done by core code.
@@ -78 +80 @@
 
 Any NOFORK applet is also a NOEXEC applet.
+
+
+    Relevant CONFIG options
+
+FEATURE_PREFER_APPLETS
+  BB_EXECVP(cmd, argv) will try to exec /proc/self/exe
+    if command's name matches some applet name
+  applet tables will contain NOFORK/NOEXEC bits
+  spawn_and_wait(argv) will do NOFORK/NOEXEC tricks
+
+FEATURE_SH_STANDALONE (needs FEATURE_PREFER_APPLETS=y)
+  shells will try to exec /proc/self/exe if command's name matches
+    some applet name
+  shells will do NOEXEC trick on NOEXEC applets
+
+FEATURE_SH_NOFORK (needs FEATURE_PREFER_APPLETS=y)
+  shells will do NOFORK trick on NOFORK applets