Do not set SHELL to utmp ever

SHELL must be set to the SHELL of the user, but it was possible set
it to utmp.

1 files changed, 11 insertions, 9 deletions

diff --git a/st.c b/st.c
index c61b90a..bcf96e9 100644
--- a/st.c
+++ b/st.c
@@ -1146,7 +1146,7 @@ die(const char *errstr, ...) {
 
 void
 execsh(void) {
-        char **args, *sh;
+        char **args, *sh, *prog;
         const struct passwd *pw;
         char buf[sizeof(long) * 8 + 1];
 
@@ -1158,13 +1158,15 @@ execsh(void) {
                         die("who are you?\n");
         }
 
-        if (utmp)
-                sh = utmp;
-        else if (pw->pw_shell[0])
-                sh = pw->pw_shell;
+        sh = (pw->pw_shell[0]) ? pw->pw_shell : shell;
+        if(opt_cmd)
+                prog = opt_cmd[0];
+        else if(utmp)
+                prog = utmp;
         else
-                sh = shell;
-        args = (opt_cmd) ? opt_cmd : (char *[]){sh, NULL};
+                prog = sh;
+        args = (opt_cmd) ? opt_cmd : (char *[]) {prog, NULL};
+
         snprintf(buf, sizeof(buf), "%lu", xw.win);
 
         unsetenv("COLUMNS");
@@ -1172,7 +1174,7 @@ execsh(void) {
         unsetenv("TERMCAP");
         setenv("LOGNAME", pw->pw_name, 1);
         setenv("USER", pw->pw_name, 1);
-        setenv("SHELL", args[0], 1);
+        setenv("SHELL", sh, 1);
         setenv("HOME", pw->pw_dir, 1);
         setenv("TERM", termname, 1);
         setenv("WINDOWID", buf, 1);
@@ -1184,7 +1186,7 @@ execsh(void) {
         signal(SIGTERM, SIG_DFL);
         signal(SIGALRM, SIG_DFL);
 
-        execvp(args[0], args);
+        execvp(prog, args);
         exit(EXIT_FAILURE);
 }