From: Masayoshi MIZUMA <m.mizuma@jp.fujitsu.com>
Subject: [PATCH] ext3: set i_extra_isize of 11th inode
Date: Fri, 20 Aug 2010 11:20:11 +0900
Message-ID: <20100820112011.E6FA.61FB500B@jp.fujitsu.com>
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Cc: linux-ext4 <linux-ext4@vger.kernel.org>
To: Andreas Dilger <adilger.kernel@dilger.ca>,
	Andrew Morton <akpm@linux-foundation.org>,
	Jan Kara <jack@suse.cz>
Sender: linux-ext4-owner@vger.kernel.org

Hi,

In ext3 filesystem, if following conditions 1., 2., 3. and 4. is satisfied,
getfattr can't search the extended attribute (EA) after remount.

Condition:
    1. the inode size is over 128 byte
    2. "lost+found" whose inode number is 11 was removed 
    3. the 11th inode is used for a file.
    4. the EA locates in-inode

This happens because of following logic:
    i_extra_isize is set to over 0 by ext3_new_inode() when we create
    a file whose inode number is 11 after removing "lost+found". 
    Therefore setfattr creates the EA in-inode.
    After remount, i_extra_isize of 11th inode is set to 0 by ext3_iget()
    when we lookup the file, so getfattr tries to search the EA out-inode.
    However, the EA locates in-inode, so getfattr can't search the EA.

How to reproduce:
    1. mkfs.ext3 -I 256 /dev/sdXX
    2. mount -o acl,user_xattr  /dev/sdXX /TEST
    3. rm -rf /TEST/*
    4. touch /TEST/file (whose inode number is 11)
    5. cd /TEST; setfattr -n user.foo0 -v bar0 file
    6. cd /TEST; getfattr -d file
       -> can see foo0/bar0
    7. umount  /dev/sdXX
    8. mount -o acl,user_xattr /dev/sdXX /TEST
    9. cd /TEST; getfattr -d file
       -> can't see foo0/bar0

Though the 11th inode is used for "lost+found" normally, the other
file can also use it. Therefore, i_extra_isize of 11th inode should be set
to the suitable value by ext3_iget().

Signed-off-by: Masayoshi MIZUMA <m.mizuma@jp.fujitsu.com>
---
 fs/ext3/inode.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 735f019..85e8574 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -2881,8 +2881,7 @@ struct inode *ext3_iget(struct super_block *sb, unsigned long ino)
 		atomic_set(&ei->i_datasync_tid, tid);
 	}
 
-	if (inode->i_ino >= EXT3_FIRST_INO(inode->i_sb) + 1 &&
-	    EXT3_INODE_SIZE(inode->i_sb) > EXT3_GOOD_OLD_INODE_SIZE) {
+	if (EXT3_INODE_SIZE(inode->i_sb) > EXT3_GOOD_OLD_INODE_SIZE) {
 		/*
 		 * When mke2fs creates big inodes it does not zero out
 		 * the unused bytes above EXT3_GOOD_OLD_INODE_SIZE,
-- 
1.6.2.5

Thanks,
Masayoshi