[src/trunk]: src/sys/dev Don't allocate block buffers on the stack. This can ...

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

details:   https://anonhg.NetBSD.org/src/rev/17ef45bc8b55
branches:  trunk
changeset: 747322:17ef45bc8b55
user:      tron <tron%NetBSD.org@localhost>
date:      Fri Sep 11 09:28:34 2009 +0000

description:
Don't allocate block buffers on the stack. This can cause stack overflows
in the kernel and breaks SSP builds.

diffstat:

 sys/dev/cgd.c |  16 +++++++++++-----
 1 files changed, 11 insertions(+), 5 deletions(-)

diffs (44 lines):

diff -r 96a7f171afbd -r 17ef45bc8b55 sys/dev/cgd.c
--- a/sys/dev/cgd.c     Fri Sep 11 06:48:50 2009 +0000
+++ b/sys/dev/cgd.c     Fri Sep 11 09:28:34 2009 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: cgd.c,v 1.58 2009/06/05 19:21:02 haad Exp $ */
+/* $NetBSD: cgd.c,v 1.59 2009/09/11 09:28:34 tron Exp $ */
 
 /*-
  * Copyright (c) 2002 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cgd.c,v 1.58 2009/06/05 19:21:02 haad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cgd.c,v 1.59 2009/09/11 09:28:34 tron Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -775,9 +775,13 @@
        struct iovec    dstiov[2];
        struct iovec    srciov[2];
        size_t          blocksize = cs->sc_cdata.cf_blocksize;
-       char            sink[blocksize];
-       char            zero_iv[blocksize];
-       char            blkno_buf[blocksize];
+       char            *sink;
+       char            *zero_iv;
+       char            *blkno_buf;
+
+       sink = malloc(blocksize * 3, M_DEVBUF, M_WAITOK);
+       zero_iv = &sink[blocksize];
+       blkno_buf = &zero_iv[blocksize];
 
        DPRINTF_FOLLOW(("cgd_cipher() dir=%d\n", dir));
 
@@ -831,6 +835,8 @@
                src += secsize;
                blkno++;
        }
+
+       free(sink, M_DEVBUF);
 }
 
 #ifdef DEBUG