Fix a bug introduced in r223938; on big-endian machines coping a 32-bit

quantum bytewise to the address of a 64-bit variable results in writing
to the "wrong" 32-bit half so adjust the address accordingly. This fix
is implemented in a hackish way for two reasons:
o in order to be able to get it into 8.3 with zero impact on the little-
  endian architectures where this bug has no effect and
o to avoid blowing the x86 boot2 out of the water again when compiling
  it with clang, which all sane versions of this fix tested do.
This change fixes booting from UFS1 file systems on big-endian machines.

MFC after:	3 days

1 files changed, 15 insertions, 0 deletions

diff --git a/sys/boot/common/ufsread.c b/sys/boot/common/ufsread.c
index b767732..d87853f 100644
--- a/sys/boot/common/ufsread.c
+++ b/sys/boot/common/ufsread.c
@@ -46,6 +46,8 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include <sys/endian.h>
+
 #include <ufs/ufs/dinode.h>
 #include <ufs/ufs/dir.h>
 #include <ufs/ffs/fs.h>
@@ -262,15 +264,28 @@ fsread(ino_t inode, void *buf, size_t nbyte)
 			}
 			n = (lbn - NDADDR) & (n - 1);
 #if defined(UFS1_ONLY)
+#if BYTE_ORDER == BIG_ENDIAN
+			memcpy((char *)&addr + sizeof(addr) -
+			    sizeof(ufs1_daddr_t), (ufs1_daddr_t *)indbuf + n,
+			    sizeof(ufs1_daddr_t));
+#else
 			memcpy(&addr, (ufs1_daddr_t *)indbuf + n,
 			    sizeof(ufs1_daddr_t));
+#endif
 #elif defined(UFS2_ONLY)
 			memcpy(&addr, (ufs2_daddr_t *)indbuf + n,
 			    sizeof(ufs2_daddr_t));
 #else
 			if (fs.fs_magic == FS_UFS1_MAGIC)
+#if BYTE_ORDER == BIG_ENDIAN
+				memcpy((char *)&addr + sizeof(addr) -
+				    sizeof(ufs1_daddr_t),
+				    (ufs1_daddr_t *)indbuf + n,
+			    	sizeof(ufs1_daddr_t));
+#else
 				memcpy(&addr, (ufs1_daddr_t *)indbuf + n,
 				    sizeof(ufs1_daddr_t));
+#endif
 			else
 				memcpy(&addr, (ufs2_daddr_t *)indbuf + n,
 				    sizeof(ufs2_daddr_t));