[PATCH] udf: fix uid/gid changing to zero

This patch fixes uid/gid changing to zero when uid/gid mount option is
used for UDF. The problem appears when the overriding uid/gid matches
inode. The fix is simple, instead of unconditionally zeroing buffer,
we now only do it for new inodes.

The regression appeared in commit "[PATCH] UDF sync with CVS" and was
first reported by Phillip Susi.

Cc: Phillip Susi <psusi@cfl.rr.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
---

 fs/udf/ialloc.c          |    1 +
 fs/udf/inode.c           |    9 +++++++--
 fs/udf/udf_i.h           |    1 +
 include/linux/udf_fs_i.h |    3 ++-
 4 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/fs/udf/ialloc.c b/fs/udf/ialloc.c
index c9b707b..4bc3dc9 100644
--- a/fs/udf/ialloc.c
+++ b/fs/udf/ialloc.c
@@ -146,6 +146,7 @@ struct inode * udf_new_inode (struct ino
 		UDF_I_ALLOCTYPE(inode) = ICBTAG_FLAG_AD_LONG;
 	inode->i_mtime = inode->i_atime = inode->i_ctime =
 		UDF_I_CRTIME(inode) = current_fs_time(inode->i_sb);
+	UDF_I_NEW_INODE(inode) = 1;
 	insert_inode_hash(inode);
 	mark_inode_dirty(inode);
 	up(&sbi->s_alloc_sem);
diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 395e582..6937da2 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -1003,6 +1003,8 @@ static void udf_fill_inode(struct inode 
 	long convtime_usec;
 	int offset;
 
+	UDF_I_NEW_INODE(inode) = 0;
+
 	fe = (struct fileEntry *)bh->b_data;
 	efe = (struct extendedFileEntry *)bh->b_data;
 
@@ -1307,11 +1309,14 @@ udf_update_inode(struct inode *inode, in
 		return -EIO;
 	}
 
-	memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
-
 	fe = (struct fileEntry *)bh->b_data;
 	efe = (struct extendedFileEntry *)bh->b_data;
 
+	if (UDF_I_NEW_INODE(inode) == 1) {
+		memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
+		UDF_I_NEW_INODE(inode) = 0;
+	}
+
 	if (le16_to_cpu(fe->descTag.tagIdent) == TAG_IDENT_USE)
 	{
 		struct unallocSpaceEntry *use =
diff --git a/fs/udf/udf_i.h b/fs/udf/udf_i.h
index d7dbe6f..87f82f7 100644
--- a/fs/udf/udf_i.h
+++ b/fs/udf/udf_i.h
@@ -16,6 +16,7 @@ static inline struct udf_inode_info *UDF
 #define UDF_I_EFE(X)		( UDF_I(X)->i_efe )
 #define UDF_I_USE(X)		( UDF_I(X)->i_use )
 #define UDF_I_STRAT4096(X)	( UDF_I(X)->i_strat4096 )
+#define UDF_I_NEW_INODE(X)	( UDF_I(X)->i_new_inode )
 #define UDF_I_NEXT_ALLOC_BLOCK(X)	( UDF_I(X)->i_next_alloc_block )
 #define UDF_I_NEXT_ALLOC_GOAL(X)	( UDF_I(X)->i_next_alloc_goal )
 #define UDF_I_CRTIME(X)		( UDF_I(X)->i_crtime )
diff --git a/include/linux/udf_fs_i.h b/include/linux/udf_fs_i.h
index 1e75084..c21415a 100644
--- a/include/linux/udf_fs_i.h
+++ b/include/linux/udf_fs_i.h
@@ -51,7 +51,8 @@ struct udf_inode_info
 	unsigned		i_efe : 1;
 	unsigned		i_use : 1;
 	unsigned		i_strat4096 : 1;
-	unsigned		reserved : 26;
+	unsigned		i_new_inode : 1;
+	unsigned		reserved : 25;
 	union
 	{
 		short_ad	*i_sad;