[src/trunk]: src/sys/kern PR/54176: Anthony Mallet:

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

details:   https://anonhg.NetBSD.org/src/rev/6e775fab1424
branches:  trunk
changeset: 456439:6e775fab1424
user:      christos <christos%NetBSD.org@localhost>
date:      Wed May 08 14:05:18 2019 +0000

description:
PR/54176: Anthony Mallet:
getsockopt(2) does not silently truncate returned optval

diffstat:

 sys/kern/uipc_socket.c |  18 ++++++------------
 1 files changed, 6 insertions(+), 12 deletions(-)

diffs (47 lines):

diff -r 92b6a25eb3e4 -r 6e775fab1424 sys/kern/uipc_socket.c
--- a/sys/kern/uipc_socket.c    Wed May 08 14:03:57 2019 +0000
+++ b/sys/kern/uipc_socket.c    Wed May 08 14:05:18 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uipc_socket.c,v 1.278 2019/04/15 10:53:17 pgoyette Exp $       */
+/*     $NetBSD: uipc_socket.c,v 1.279 2019/05/08 14:05:18 christos Exp $       */
 
 /*
  * Copyright (c) 2002, 2007, 2008, 2009 The NetBSD Foundation, Inc.
@@ -71,7 +71,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.278 2019/04/15 10:53:17 pgoyette Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.279 2019/05/08 14:05:18 christos Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_compat_netbsd.h"
@@ -2082,11 +2082,8 @@
                        return error;
        }
 
-       if (sopt->sopt_size < len)
-               return EINVAL;
-
-       memcpy(sopt->sopt_data, buf, len);
-       sopt->sopt_retsize = len;
+       sopt->sopt_retsize = MIN(sopt->sopt_size, len);
+       memcpy(sopt->sopt_data, buf, sopt->sopt_retsize);
 
        return 0;
 }
@@ -2146,12 +2143,9 @@
                        return error;
        }
 
-       if (sopt->sopt_size < len)
-               return EINVAL;
-
-       m_copydata(m, 0, len, sopt->sopt_data);
+       sopt->sopt_retsize = MIN(sopt->sopt_size, len);
+       m_copydata(m, 0, sopt->sopt_retsize, sopt->sopt_data);
        m_freem(m);
-       sopt->sopt_retsize = len;
 
        return 0;
 }