libbb: consolidate NOMMU fix of restoring high bit in argv[0][0]

function                                             old     new   delta
fork_or_rexec                                         46      56     +10
bootchartd_main                                     1087    1079      -8
cpio_main                                            674     661     -13
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/2 up/down: 10/-21)            Total: -11 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c
index 79141936a..a570ddbf2 100644
--- a/libbb/vfork_daemon_rexec.c
+++ b/libbb/vfork_daemon_rexec.c
@@ -268,10 +268,12 @@ pid_t FAST_FUNC fork_or_rexec(char **argv)
         /* fflush_all(); ? - so far all callers had no buffered output to flush */
 
         pid = xvfork();
-        if (pid) /* parent */
-                return pid;
-        /* child - re-exec ourself */
-        re_exec(argv);
+        if (pid == 0) /* child - re-exec ourself */
+                re_exec(argv); /* NORETURN */
+
+        /* parent */
+        argv[0][0] &= 0x7f; /* undo re_rexec() damage */
+        return pid;
 }
 #endif