su: expand help; simplify passing of -c CMD to run_shell()

Also, added a comment about bug 9401 (TIOCSTI input injection).

function                                             old     new   delta
packed_usage                                       30909   30932     +23
su_main                                              470     487     +17
sulogin_main                                         260     258      -2
run_applet_and_exit                                  681     678      -3
run_shell                                            166     126     -40

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

1 files changed, 1 insertions, 1 deletions

diff --git a/libbb/executable.c b/libbb/executable.c
index 05e70312f..3a1d4ff44 100644
--- a/libbb/executable.c
+++ b/libbb/executable.c
@@ -97,5 +97,5 @@ void FAST_FUNC exec_prog_or_SHELL(char **argv)
         if (argv[0]) {
                 BB_EXECVP_or_die(argv);
         }
-        run_shell(getenv("SHELL"), /*login:*/ 1, NULL, NULL);
+        run_shell(getenv("SHELL"), /*login:*/ 1, NULL);
 }