[src/trunk]: src/lib/librumphijack disallow mmap(MAP_FILE) from a rump kernel fd

[pooka <pooka%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e72ca1d81a99
branches:  trunk
changeset: 762471:e72ca1d81a99
user:      pooka <pooka%NetBSD.org@localhost>
date:      Mon Feb 21 13:19:35 2011 +0000

description:
disallow mmap(MAP_FILE) from a rump kernel fd

diffstat:

 lib/librumphijack/hijack.c |  21 +++++++++++++++++++--
 1 files changed, 19 insertions(+), 2 deletions(-)

diffs (63 lines):

diff -r 642d22afc75a -r e72ca1d81a99 lib/librumphijack/hijack.c
--- a/lib/librumphijack/hijack.c        Mon Feb 21 13:04:22 2011 +0000
+++ b/lib/librumphijack/hijack.c        Mon Feb 21 13:19:35 2011 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: hijack.c,v 1.61 2011/02/21 12:55:21 pooka Exp $       */
+/*      $NetBSD: hijack.c,v 1.62 2011/02/21 13:19:35 pooka Exp $       */
 
 /*-
  * Copyright (c) 2011 Antti Kantee.  All Rights Reserved.
@@ -26,7 +26,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: hijack.c,v 1.61 2011/02/21 12:55:21 pooka Exp $");
+__RCSID("$NetBSD: hijack.c,v 1.62 2011/02/21 13:19:35 pooka Exp $");
 
 #define __ssp_weak_name(fun) _hijack_ ## fun
 
@@ -34,6 +34,7 @@
 #include <sys/types.h>
 #include <sys/event.h>
 #include <sys/ioctl.h>
+#include <sys/mman.h>
 #include <sys/mount.h>
 #include <sys/poll.h>
 #include <sys/socket.h>
@@ -225,6 +226,7 @@
 pid_t  (*host_fork)(void);
 int    (*host_daemon)(int, int);
 int    (*host_execve)(const char *, char *const[], char *const[]);
+void * (*host_mmap)(void *, size_t, int, int, int, off_t);
 
 /* ok, we need *two* bits per dup2'd fd to track fd+HIJACKOFF aliases */
 static uint32_t dup2mask;
@@ -454,6 +456,7 @@
        host_fork = dlsym(RTLD_NEXT, "fork");
        host_daemon = dlsym(RTLD_NEXT, "daemon");
        host_execve = dlsym(RTLD_NEXT, "execve");
+       host_mmap = dlsym(RTLD_NEXT, "mmap");
 
        /*
         * In theory cannot print anything during lookups because
@@ -1527,6 +1530,20 @@
 }
 
 /*
+ * mmapping from a rump kernel is not supported, so disallow it.
+ */
+void *
+mmap(void *addr, size_t len, int prot, int flags, int fd, off_t offset)
+{
+
+       if (flags & MAP_FILE && fd_isrump(fd)) {
+               errno = ENOSYS;
+               return MAP_FAILED;
+       }
+       return host_mmap(addr, len, prot, flags, fd, offset);
+}
+
+/*
  * Rest are std type calls.
  */