*: s/"/bin/sh"/DEFAULT_SHELL, run_shell() API fix, remove unneeded strdup

function                                             old     new   delta
run_shell                                            157     166      +9
su_main                                              477     470      -7
sulogin_main                                         515     503     -12

Signed-off-by: Ladislav Michl <Ladislav.Michl@seznam.cz>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/archival/libunarchive/data_extract_to_command.c b/archival/libunarchive/data_extract_to_command.c
index 53a7217c2580f5d12949721e75a92e3c400be1be..eb09439bc5e1a38274bcfb849dc6c9c592b3787f 100644 (file)
--- a/archival/libunarchive/data_extract_to_command.c
+++ b/archival/libunarchive/data_extract_to_command.c
@@ -102,8 +102,8 @@ void FAST_FUNC data_extract_to_command(archive_handle_t *archive_handle)
                        close(p[1]);
                        xdup2(p[0], STDIN_FILENO);
                        signal(SIGPIPE, SIG_DFL);
-                       execl("/bin/sh", "/bin/sh" + 5, "-c", archive_handle->tar__to_command, NULL);
-                       bb_perror_msg_and_die("can't execute '%s'", "/bin/sh");
+                       execl(DEFAULT_SHELL, DEFAULT_SHELL_SHORT_NAME, "-c", archive_handle->tar__to_command, NULL);
+                       bb_perror_msg_and_die("can't execute '%s'", DEFAULT_SHELL);
                }
                close(p[0]);
                /* Our caller is expected to do signal(SIGPIPE, SIG_IGN)

diff --git a/include/libbb.h b/include/libbb.h
index 58719a85b3581cf3535b5c6d66fe1e5b6c70bbc0..53b768d88fe1985bddb77818728138fba1bdd037 100644 (file)
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -1157,7 +1157,6 @@ char *bb_simplify_abs_path_inplace(char *path) FAST_FUNC;
 extern void bb_do_delay(int seconds) FAST_FUNC;
 extern void change_identity(const struct passwd *pw) FAST_FUNC;
 extern void run_shell(const char *shell, int loginshell, const char *command, const char **additional_args) NORETURN FAST_FUNC;
-extern void run_shell(const char *shell, int loginshell, const char *command, const char **additional_args) FAST_FUNC;
 #if ENABLE_SELINUX
 extern void renew_current_security_context(void) FAST_FUNC;
 extern void set_current_security_context(security_context_t sid) FAST_FUNC;
@@ -1593,12 +1592,12 @@ extern struct globals *const ptr_to_globals;
  * use bb_default_login_shell and following defines.
  * If you change LIBBB_DEFAULT_LOGIN_SHELL,
  * don't forget to change increment constant. */
-#define LIBBB_DEFAULT_LOGIN_SHELL      "-/bin/sh"
+#define LIBBB_DEFAULT_LOGIN_SHELL  "-/bin/sh"
 extern const char bb_default_login_shell[];
 /* "/bin/sh" */
-#define DEFAULT_SHELL     (bb_default_login_shell+1)
+#define DEFAULT_SHELL              (bb_default_login_shell+1)
 /* "sh" */
-#define DEFAULT_SHELL_SHORT_NAME     (bb_default_login_shell+6)
+#define DEFAULT_SHELL_SHORT_NAME   (bb_default_login_shell+6)
 
 #if ENABLE_FEATURE_DEVFS
 # define CURRENT_VC "/dev/vc/0"

diff --git a/libbb/run_shell.c b/libbb/run_shell.c
index 4608a24a91f73240b4e2a44de58dba92ace1fd0a..4d92c3caa10266dd6e9bba46cf27aad7f014e1a3 100644 (file)
--- a/libbb/run_shell.c
+++ b/libbb/run_shell.c
@@ -49,15 +49,14 @@ void FAST_FUNC set_current_security_context(security_context_t sid)
 
 #endif
 
-/* Run SHELL, or DEFAULT_SHELL if SHELL is empty.
-   If COMMAND is nonzero, pass it to the shell with the -c option.
-   If ADDITIONAL_ARGS is nonzero, pass it to the shell as more
-   arguments.  */
-
+/* Run SHELL, or DEFAULT_SHELL if SHELL is "" or NULL.
+ * If COMMAND is nonzero, pass it to the shell with the -c option.
+ * If ADDITIONAL_ARGS is nonzero, pass it to the shell as more
+ * arguments.  */
 void FAST_FUNC run_shell(const char *shell, int loginshell, const char *command, const char **additional_args)
 {
        const char **args;
-       int argno = 1;
+       int argno;
        int additional_args_cnt = 0;
 
        for (args = additional_args; args && *args; args++)
@@ -65,11 +64,13 @@ void FAST_FUNC run_shell(const char *shell, int loginshell, const char *command,
 
        args = xmalloc(sizeof(char*) * (4 + additional_args_cnt));
 
-       args[0] = bb_get_last_path_component_nostrip(xstrdup(shell));
+       if (!shell || !shell[0])
+               shell = DEFAULT_SHELL;
 
+       args[0] = bb_get_last_path_component_nostrip(shell);
        if (loginshell)
                args[0] = xasprintf("-%s", args[0]);
-
+       argno = 1;
        if (command) {
                args[argno++] = "-c";
                args[argno++] = command;
@@ -79,6 +80,7 @@ void FAST_FUNC run_shell(const char *shell, int loginshell, const char *command,
                        args[argno++] = *additional_args;
        }
        args[argno] = NULL;
+
 #if ENABLE_SELINUX
        if (current_sid)
                setexeccon(current_sid);

diff --git a/libbb/setup_environment.c b/libbb/setup_environment.c
index 13e60d8e422d05bc2095c493a8f39498107c8f90..a95fbc5bfc4da7dd967fea91720f2c50ecf1619d 100644 (file)
--- a/libbb/setup_environment.c
+++ b/libbb/setup_environment.c
@@ -43,7 +43,7 @@ void FAST_FUNC setup_environment(const char *shell, int flags, const struct pass
                const char *term;
 
                /* Leave TERM unchanged. Set HOME, SHELL, USER, LOGNAME, PATH.
-                  Unset all other environment variables.  */
+                * Unset all other environment variables.  */
                term = getenv("TERM");
                clearenv();
                if (term)
@@ -57,7 +57,7 @@ void FAST_FUNC setup_environment(const char *shell, int flags, const struct pass
                //xsetenv("SHELL",   shell);
        } else if (flags & SETUP_ENV_CHANGEENV) {
                /* Set HOME, SHELL, and if not becoming a super-user,
-                  USER and LOGNAME.  */
+                * USER and LOGNAME.  */
                if (pw->pw_uid) {
  shortcut:
                        xsetenv("USER",    pw->pw_name);

diff --git a/loginutils/login.c b/loginutils/login.c
index 078cd68ed40c94437afe4cd4b5a434384888f156..88ed0af7822400fab93afdcd29e427baa47454d0 100644 (file)
--- a/loginutils/login.c
+++ b/loginutils/login.c
@@ -201,7 +201,7 @@ int login_main(int argc UNUSED_PARAM, char **argv)
        };
        char *fromhost;
        char username[USERNAME_SIZE];
-       const char *tmp;
+       const char *shell;
        int run_by_root;
        unsigned opt;
        int count = 0;
@@ -389,10 +389,10 @@ int login_main(int argc UNUSED_PARAM, char **argv)
                run_login_script(pw, full_tty);
 
        change_identity(pw);
-       tmp = pw->pw_shell;
-       if (!tmp || !*tmp)
-               tmp = DEFAULT_SHELL;
-       setup_environment(tmp,
+       shell = pw->pw_shell;
+       if (!shell || !shell[0])
+               shell = DEFAULT_SHELL;
+       setup_environment(shell,
                        (!(opt & LOGIN_OPT_p) * SETUP_ENV_CLEARENV) + SETUP_ENV_CHANGEENV,
                        pw);
 
@@ -427,7 +427,7 @@ int login_main(int argc UNUSED_PARAM, char **argv)
        signal(SIGINT, SIG_DFL);
 
        /* Exec login shell with no additional parameters */
-       run_shell(tmp, 1, NULL, NULL);
+       run_shell(shell, 1, NULL, NULL);
 
        /* return EXIT_FAILURE; - not reached */
 }

diff --git a/loginutils/su.c b/loginutils/su.c
index af25655fd4986ca4eba4523917c42b9e26a0ceb1..9bae375515105266de781d459ad60fcaed08717b 100644 (file)
--- a/loginutils/su.c
+++ b/loginutils/su.c
@@ -10,23 +10,27 @@
 
 #if ENABLE_FEATURE_SU_CHECKS_SHELLS
 /* Return 1 if SHELL is a restricted shell (one not returned by
-   getusershell), else 0, meaning it is a standard shell.  */
+ * getusershell), else 0, meaning it is a standard shell.  */
 static int restricted_shell(const char *shell)
 {
        char *line;
+       int result = 1;
 
        /*setusershell(); - getusershell does it itself*/
        while ((line = getusershell()) != NULL) {
-               if (/* *line != '#' && */ strcmp(line, shell) == 0)
-                       return 0;
+               if (/* *line != '#' && */ strcmp(line, shell) == 0) {
+                       result = 0;
+                       break;
+               }
        }
-       endusershell();
-       return 1;
+       if (ENABLE_FEATURE_CLEAN_UP)
+               endusershell();
+       return result;
 }
 #endif
 
 #define SU_OPT_mp (3)
-#define SU_OPT_l (4)
+#define SU_OPT_l  (4)
 
 int su_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int su_main(int argc UNUSED_PARAM, char **argv)
@@ -38,7 +42,8 @@ int su_main(int argc UNUSED_PARAM, char **argv)
        struct passwd *pw;
        uid_t cur_uid = getuid();
        const char *tty;
-       char *old_user;
+       char user_buf[64];
+       const char *old_user;
 
        flags = getopt32(argv, "mplc:s:", &opt_command, &opt_shell);
        //argc -= optind;
@@ -56,21 +61,18 @@ int su_main(int argc UNUSED_PARAM, char **argv)
        }
 
        if (ENABLE_FEATURE_SU_SYSLOG) {
-               /* The utmp entry (via getlogin) is probably the best way to identify
-                * the user, especially if someone su's from a su-shell.
+               /* The utmp entry (via getlogin) is probably the best way to
+                * identify the user, especially if someone su's from a su-shell.
                 * But getlogin can fail -- usually due to lack of utmp entry.
                 * in this case resort to getpwuid.  */
-               const char *user;
 #if ENABLE_FEATURE_UTMP
-               char user_buf[64];
-               user = user_buf;
+               old_user = user_buf;
                if (getlogin_r(user_buf, sizeof(user_buf)) != 0)
 #endif
                {
                        pw = getpwuid(cur_uid);
-                       user = pw ? pw->pw_name : "";
+                       old_user = pw ? xstrdup(pw->pw_name) : "";
                }
-               old_user = xstrdup(user);
                tty = xmalloc_ttyname(2);
                if (!tty) {
                        tty = "none";
@@ -80,13 +82,7 @@ int su_main(int argc UNUSED_PARAM, char **argv)
 
        pw = xgetpwnam(opt_username);
 
-       /* Make sure pw->pw_shell is non-NULL.  It may be NULL when NEW_USER
-          is a username that is retrieved via NIS (YP), but that doesn't have
-          a default shell listed.  */
-       if (!pw->pw_shell || !pw->pw_shell[0])
-               pw->pw_shell = (char *)DEFAULT_SHELL;
-
-       if ((cur_uid == 0) || correct_password(pw)) {
+       if (cur_uid == 0 || correct_password(pw)) {
                if (ENABLE_FEATURE_SU_SYSLOG)
                        syslog(LOG_NOTICE, "%c %s %s:%s",
                                '+', tty, old_user, opt_username);
@@ -99,21 +95,30 @@ int su_main(int argc UNUSED_PARAM, char **argv)
 
        if (ENABLE_FEATURE_CLEAN_UP && ENABLE_FEATURE_SU_SYSLOG) {
                closelog();
-               free(old_user);
        }
 
-       if (!opt_shell && (flags & SU_OPT_mp))
+       if (!opt_shell && (flags & SU_OPT_mp)) {
+               /* -s SHELL is not given, but "preserve env" opt is */
                opt_shell = getenv("SHELL");
+       }
+
+       /* Make sure pw->pw_shell is non-NULL.  It may be NULL when NEW_USER
+        * is a username that is retrieved via NIS (YP), that doesn't have
+        * a default shell listed.  */
+       if (!pw->pw_shell || !pw->pw_shell[0])
+               pw->pw_shell = (char *)DEFAULT_SHELL;
 
 #if ENABLE_FEATURE_SU_CHECKS_SHELLS
        if (opt_shell && cur_uid != 0 && restricted_shell(pw->pw_shell)) {
                /* The user being su'd to has a nonstandard shell, and so is
-                  probably a uucp account or has restricted access.  Don't
-                  compromise the account by allowing access with a standard
-                  shell.  */
+                * probably a uucp account or has restricted access.  Don't
+                * compromise the account by allowing access with a standard
+                * shell.  */
                bb_error_msg("using restricted shell");
                opt_shell = NULL;
        }
+       /* else: user can run whatever he wants via "su -s PROG USER".
+        * This is safe since PROG is run under user's uid/gid. */
 #endif
        if (!opt_shell)
                opt_shell = pw->pw_shell;

diff --git a/loginutils/sulogin.c b/loginutils/sulogin.c
index 6e3d3b0190922c08ca11c6a366f450246a540e7b..3516013f15ea2cd6dec6f4fcc68da55f907badc2 100644 (file)
--- a/loginutils/sulogin.c
+++ b/loginutils/sulogin.c
@@ -101,11 +101,9 @@ int sulogin_main(int argc UNUSED_PARAM, char **argv)
        shell = getenv("SUSHELL");
        if (!shell)
                shell = getenv("sushell");
-       if (!shell) {
-               shell = "/bin/sh";
-               if (pwd->pw_shell[0])
-                       shell = pwd->pw_shell;
-       }
+       if (!shell)
+               shell = pwd->pw_shell;
+
        /* Exec login shell with no additional parameters. Never returns. */
        run_shell(shell, 1, NULL, NULL);
 

diff --git a/runit/svlogd.c b/runit/svlogd.c
index fc8b4abb9ea52f9473c3d65a5ec3effdc915e3a6..9fe81b900d2cbd9de520ff812c1a69ea009e4be6 100644 (file)
--- a/runit/svlogd.c
+++ b/runit/svlogd.c
@@ -354,7 +354,7 @@ static void processorstart(struct logdir *ld)
                xmove_fd(fd, 5);
 
 // getenv("SHELL")?
-               execl("/bin/sh", "/bin/sh" + 5, "-c", ld->processor, (char*) NULL);
+               execl(DEFAULT_SHELL, DEFAULT_SHELL_SHORT_NAME, "-c", ld->processor, (char*) NULL);
                bb_perror_msg_and_die(FATAL"can't %s processor %s", "run", ld->name);
        }
        ld->fnsave[26] = sv_ch; /* ...restore */