pass a copy of argv[i] to NOFORK applets (they may permute it etc).

set/save/restore more shared global variables whan call one applet from another

1 files changed, 18 insertions, 14 deletions

diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index ce5a627ed..7dbc152e2 100644
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -119,11 +119,16 @@ int spawn_and_wait(char **argv)
                 if (a->nofork)
 #endif
                 {
-                        int old_sleep = die_sleep;
+                        /* Save some shared globals */
+                        const struct bb_applet *old_a = current_applet;
                         int old_x = xfunc_error_retval;
                         uint32_t old_m = option_mask32;
+                        int old_sleep = die_sleep;
 
+                        current_applet = a;
+                        applet_name = a->name;
                         xfunc_error_retval = EXIT_FAILURE;
+                        /*option_mask32 = 0; - not needed */
                         /* special flag for xfunc_die(). If xfunc will "die"
                          * in NOFORK applet, xfunc_die() sees negative
                          * die_sleep and longjmp here instead. */
@@ -131,25 +136,24 @@ int spawn_and_wait(char **argv)
 
                         rc = setjmp(die_jmp);
                         if (!rc) {
-                                const struct bb_applet *old_a = current_applet;
-                                current_applet = a;
-                                applet_name = a->name;
-// what else should we save/restore?
-// TODO: what if applet will mangle argv vector?
-// xargs needs argv untouched because it frees argv[i]!
-// shouldn't we pass a copy?
-                                rc = a->main(argc, argv);
-                                current_applet = old_a;
-                                applet_name = old_a->name;                                      
-                        } else {
-                                /* xfunc died in NOFORK applet */
+                                /* Some callers (xargs)
+                                 * need argv untouched because they free argv[i]! */
+                                char *tmp_argv[argc+1];
+                                memcpy(tmp_argv, argv, (argc+1) * sizeof(tmp_argv[0]));
+                                /* Finally we can call NOFORK applet's main() */
+                                rc = a->main(argc, tmp_argv);
+                        } else { /* xfunc died in NOFORK applet */
+                                /* in case they meant to return 0... */
                                 if (rc == -111)
                                         rc = 0;
                         }
 
-                        die_sleep = old_sleep;
+                        /* Restoring globals */
+                        current_applet = old_a;
+                        applet_name = old_a->name;                                      
                         xfunc_error_retval = old_x;
                         option_mask32 = old_m;
+                        die_sleep = old_sleep;
                         return rc;
                 }
 #if BB_MMU