ash: fix a bug in standalone mode (corrupted getopt() state)

5 files changed, 43 insertions, 33 deletions

diff --git a/libbb/getopt32.c b/libbb/getopt32.c
index 43fb6eb86..49fb5335d 100644
--- a/libbb/getopt32.c
+++ b/libbb/getopt32.c
@@ -515,28 +515,6 @@ getopt32(char **argv, const char *applet_opts, ...)
                 }
         }
 
-        /* In case getopt32 was already called:
-         * reset the libc getopt() function, which keeps internal state.
-         *
-         * BSD-derived getopt() functions require that optind be set to 1 in
-         * order to reset getopt() state.  This used to be generally accepted
-         * way of resetting getopt().  However, glibc's getopt()
-         * has additional getopt() state beyond optind, and requires that
-         * optind be set to zero to reset its state.  So the unfortunate state of
-         * affairs is that BSD-derived versions of getopt() misbehave if
-         * optind is set to 0 in order to reset getopt(), and glibc's getopt()
-         * will core dump if optind is set 1 in order to reset getopt().
-         *
-         * More modern versions of BSD require that optreset be set to 1 in
-         * order to reset getopt().   Sigh.  Standards, anyone?
-         */
-#ifdef __GLIBC__
-        optind = 0;
-#else /* BSD style */
-        optind = 1;
-        /* optreset = 1; */
-#endif
-        /* optarg = NULL; opterr = 0; optopt = 0; - do we need this?? */
         pargv = NULL;
 
         /* Note: just "getopt() <= 0" will not work well for
diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index da0dc03e5..17b373cd1 100644
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -125,6 +125,7 @@ int FAST_FUNC run_nofork_applet_prime(struct nofork_save_area *old, int applet_n
         int rc, argc;
 
         applet_name = APPLET_NAME(applet_no);
+
         xfunc_error_retval = EXIT_FAILURE;
 
         /* Special flag for xfunc_die(). If xfunc will "die"
@@ -132,7 +133,30 @@ int FAST_FUNC run_nofork_applet_prime(struct nofork_save_area *old, int applet_n
          * die_sleep and longjmp here instead. */
         die_sleep = -1;
 
-        /* option_mask32 = 0; - not needed */
+        /* In case getopt() or getopt32() was already called:
+         * reset the libc getopt() function, which keeps internal state.
+         *
+         * BSD-derived getopt() functions require that optind be set to 1 in
+         * order to reset getopt() state.  This used to be generally accepted
+         * way of resetting getopt().  However, glibc's getopt()
+         * has additional getopt() state beyond optind, and requires that
+         * optind be set to zero to reset its state.  So the unfortunate state of
+         * affairs is that BSD-derived versions of getopt() misbehave if
+         * optind is set to 0 in order to reset getopt(), and glibc's getopt()
+         * will core dump if optind is set 1 in order to reset getopt().
+         *
+         * More modern versions of BSD require that optreset be set to 1 in
+         * order to reset getopt().  Sigh.  Standards, anyone?
+         */
+#ifdef __GLIBC__
+        optind = 0;
+#else /* BSD style */
+        optind = 1;
+        /* optreset = 1; */
+#endif
+        /* optarg = NULL; opterr = 1; optopt = 63; - do we need this too? */
+        /* (values above are what they initialized to in glibc and uclibc) */
+        /* option_mask32 = 0; - not needed, no applet depends on it being 0 */
 
         argc = 1;
         while (argv[argc])
@@ -161,8 +185,16 @@ int FAST_FUNC run_nofork_applet_prime(struct nofork_save_area *old, int applet_n
                         rc = 0;
         }
 
-        /* Restoring globals */
+        /* Restoring some globals */
         restore_nofork_data(old);
+
+        /* Other globals can be simply reset to defaults */
+#ifdef __GLIBC__
+        optind = 0;
+#else /* BSD style */
+        optind = 1;
+#endif
+
         return rc & 0xff; /* don't confuse people with "exitcodes" >255 */
 }
 
diff --git a/shell/ash_test/ash-standalone/nofork_trashes_getopt.right b/shell/ash_test/ash-standalone/nofork_trashes_getopt.right
new file mode 100644
index 000000000..573541ac9
--- /dev/null
+++ b/shell/ash_test/ash-standalone/nofork_trashes_getopt.right
@@ -0,0 +1 @@
+0
diff --git a/shell/ash_test/ash-standalone/nofork_trashes_getopt.tests b/shell/ash_test/ash-standalone/nofork_trashes_getopt.tests
new file mode 100755
index 000000000..f42c50730
--- /dev/null
+++ b/shell/ash_test/ash-standalone/nofork_trashes_getopt.tests
@@ -0,0 +1,6 @@
+# In this test, rm is NOFORK and it modifies getopt internal state
+rm -f non_existent_file
+# Subsequent hexdump is run as NOEXEC, and thus still uses this state
+hexdump </dev/null
+# Did hexdump segfault etc?
+echo $?
diff --git a/util-linux/getopt.c b/util-linux/getopt.c
index 402630385..8b5e46c7b 100644
--- a/util-linux/getopt.c
+++ b/util-linux/getopt.c
@@ -142,7 +142,8 @@ static const char *normalize(const char *arg)
  * Other settings are found in global variables.
  */
 #if !ENABLE_GETOPT_LONG
-#define generate_output(argv,argc,optstr,longopts) generate_output(argv,argc,optstr)
+#define generate_output(argv,argc,optstr,longopts) \
+        generate_output(argv,argc,optstr)
 #endif
 static int generate_output(char **argv, int argc, const char *optstr, const struct option *longopts)
 {
@@ -156,14 +157,6 @@ static int generate_output(char **argv, int argc, const char *optstr, const stru
         if (quiet_errors) /* No error reporting from getopt(3) */
                 opterr = 0;
 
-        /* Reset getopt(3) (see libbb/getopt32.c for long rant) */
-#ifdef __GLIBC__
-        optind = 0;
-#else /* BSD style */
-        optind = 1;
-        /* optreset = 1; */
-#endif
-
         while (1) {
                 opt =
 #if ENABLE_GETOPT_LONG