restore: set the zero limit for RLIMIT_CORE

This should be done to prevent generating core files, if a process was
killed by SIGSEGV, SIGBUS, etc

https://bugzilla.openvz.org/show_bug.cgi?id=2655

Looks-good-to: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-restore.c

@@ -737,8 +737,13 @@ static int restore_one_zombie(int pid, CoreEntry *core)
 	}
 
 	if (exit_code & 0x7f) {
+		struct rlimit rlim = {0, 0};
 		int signr;
 
+		/* prevent generating core files */
+		if (setrlimit(RLIMIT_CORE, &rlim))
+			pr_perror("Can't set the zero limit for core files");
+
 		signr = exit_code & 0x7F;
 		if (!sig_fatal(signr)) {
 			pr_warn("Exit with non fatal signal ignored\n");