Patch by Guillaume Morin

Fix two race conditions, as described at.
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=212764

diff --git a/init/init.c b/init/init.c
index 85792c9b7f1fe1a4263a7d2c3793e7428a42d838..d332ccdbe13e8d219d0e3ebe53f389ad0a56dde8 100644 (file)
--- a/init/init.c
+++ b/init/init.c
@@ -500,7 +500,12 @@ static pid_t run(const struct init_action *a)
                                signal(SIGCHLD, SIG_DFL);
 
                                /* Wait for child to exit */
-                               while ((tmp_pid = waitpid(pid, &junk, 0)) != pid);
+                               while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
+                                       if (tmp_pid == -1 && errno == ECHILD) {
+                                               break;
+                                       }
+                                       /* FIXME handle other errors */
+                }
 
                                /* See if stealing the controlling tty back is necessary */
                                pgrp = tcgetpgrp(0);
@@ -624,12 +629,15 @@ static int waitfor(const struct init_action *a)
 
        pid = run(a);
        while (1) {
-               wpid = wait(&status);
-               if (wpid > 0 && wpid != pid) {
-                       continue;
-               }
+               wpid = waitpid(pid,&status,0);
                if (wpid == pid)
                        break;
+               if (wpid == -1 && errno == ECHILD) {
+                       /* we missed its termination */
+                       break;
+               }
+               /* FIXME other errors should maybe trigger an error, but allow
+                * the program to continue */
        }
        return wpid;
 }