[src/trunk]: src/sys/fs/efs fix unaligned access

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

details:   https://anonhg.NetBSD.org/src/rev/da459db98341
branches:  trunk
changeset: 938341:da459db98341
user:      christos <christos%NetBSD.org@localhost>
date:      Mon Sep 07 00:11:47 2020 +0000

description:
fix unaligned access

diffstat:

 sys/fs/efs/efs_subr.c |  12 +++++++-----
 1 files changed, 7 insertions(+), 5 deletions(-)

diffs (36 lines):

diff -r 1ad3ee50b4f7 -r da459db98341 sys/fs/efs/efs_subr.c
--- a/sys/fs/efs/efs_subr.c     Sun Sep 06 23:23:21 2020 +0000
+++ b/sys/fs/efs/efs_subr.c     Mon Sep 07 00:11:47 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: efs_subr.c,v 1.12 2015/09/26 12:16:28 maxv Exp $       */
+/*     $NetBSD: efs_subr.c,v 1.13 2020/09/07 00:11:47 christos Exp $   */
 
 /*
  * Copyright (c) 2006 Stephen M. Rumble <rumble%ephemeral.org@localhost>
@@ -17,7 +17,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: efs_subr.c,v 1.12 2015/09/26 12:16:28 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: efs_subr.c,v 1.13 2020/09/07 00:11:47 christos Exp $");
 
 #include <sys/param.h>
 #include <sys/kauth.h>
@@ -63,12 +63,14 @@
 {
        int i;
        int32_t cksum;
-       uint16_t *sbarray = (uint16_t *)esb;
+       uint8_t *sbarray = (uint8_t *)esb;
 
        KASSERT((EFS_SB_CHECKSUM_SIZE % 2) == 0);
 
-       for (i = cksum = 0; i < (EFS_SB_CHECKSUM_SIZE / 2); i++) {
-               cksum ^= be16toh(sbarray[i]);
+       for (i = cksum = 0; i < EFS_SB_CHECKSUM_SIZE; i += 2) {
+               uint16_t v;
+               memcpy(&v, &sbarray[i], sizeof(v));
+               cksum ^= be16toh(v);
                cksum  = (cksum << 1) | (new && cksum < 0);
        }