inetd: be more careful with syslog socket; other small fixes

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

1 files changed, 18 insertions, 7 deletions

diff --git a/networking/inetd.c b/networking/inetd.c
index 331c49441..4b9d01294 100644
--- a/networking/inetd.c
+++ b/networking/inetd.c
@@ -1031,10 +1031,10 @@ static void reap_child(int sig UNUSED_PARAM)
                                 continue;
                         /* One of our "wait" services */
                         if (WIFEXITED(status) && WEXITSTATUS(status))
-                                bb_error_msg("%s: exit status 0x%x",
+                                bb_error_msg("%s: exit status %u",
                                                 sep->se_program, WEXITSTATUS(status));
                         else if (WIFSIGNALED(status))
-                                bb_error_msg("%s: exit signal 0x%x",
+                                bb_error_msg("%s: exit signal %u",
                                                 sep->se_program, WTERMSIG(status));
                         sep->se_wait = 1;
                         add_fd_to_set(sep->se_fd);
@@ -1119,7 +1119,12 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
         else
                 bb_sanitize_stdio();
         if (!(opt & 4)) {
-                openlog(applet_name, LOG_PID, LOG_DAEMON);
+                /* LOG_NDELAY: connect to syslog daemon NOW.
+                 * Otherwise, we may open syslog socket
+                 * in vforked child, making opened fds and syslog()
+                 * internal state inconsistent.
+                 * This was observed to leak file descriptors. */
+                openlog(applet_name, LOG_PID | LOG_NDELAY, LOG_DAEMON);
                 logmode = LOGMODE_SYSLOG;
         }
 
@@ -1355,17 +1360,23 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
                         if (rlim_ofile.rlim_cur != rlim_ofile_cur)
                                 if (setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
                                         bb_perror_msg("setrlimit");
-                        closelog();
+
+                        /*closelog(); - BAD, we are after vfork,
+                         * this may confuse syslog() state.
+                         * Let's hope libc set syslog fd to CLOEXEC...
+                         */
                         xmove_fd(ctrl, STDIN_FILENO);
                         xdup2(STDIN_FILENO, STDOUT_FILENO);
                         /* manpages of inetd I managed to find either say
                          * that stderr is also redirected to the network,
                          * or do not talk about redirection at all (!) */
-                        xdup2(STDIN_FILENO, STDERR_FILENO);
-                        /* NB: among others, this loop closes listening socket
+                        if (!sep->se_wait) /* only for usual "tcp nowait" */
+                                xdup2(STDIN_FILENO, STDERR_FILENO);
+                        /* NB: among others, this loop closes listening sockets
                          * for nowait stream children */
                         for (sep2 = serv_list; sep2; sep2 = sep2->se_next)
-                                maybe_close(sep2->se_fd);
+                                if (sep2->se_fd != ctrl)
+                                        maybe_close(sep2->se_fd);
                         sigaction_set(SIGPIPE, &saved_pipe_handler);
                         restore_sigmask(&omask);
                         BB_EXECVP(sep->se_program, sep->se_argv);