2006-11-16 02:44:40

by Chris Wright

[permalink] [raw]
Subject: [patch 08/30] fix UFS superblock alignment issues

-stable review patch. If anyone has any objections, please let us know.
------------------

From: Eric Sandeen <[email protected]>

ufs2 fails to mount on x86_64, claiming bad magic. This is because
ufs_super_block_third's fs_un1 member is padded out by 4 bytes for 8-byte
alignment, pushing down the rest of the struct.

Forcing this to be packed solves it. I took a quick look over other
on-disk structures and didn't immediately find other problems. I was able
to mount & ls a populated ufs2 filesystem w/ this change.

Signed-off-by: Eric Sandeen <[email protected]>
Cc: Evgeniy Dushistov <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
---
include/linux/ufs_fs.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- linux-2.6.18.2.orig/include/linux/ufs_fs.h
+++ linux-2.6.18.2/include/linux/ufs_fs.h
@@ -900,7 +900,7 @@ struct ufs_super_block_third {
__fs64 fs_csaddr; /* blk addr of cyl grp summary area */
__fs64 fs_pendingblocks;/* blocks in process of being freed */
__fs32 fs_pendinginodes;/*inodes in process of being freed */
- } fs_u2;
+ } __attribute__ ((packed)) fs_u2;
} fs_un1;
union {
struct {

--