From: Jan Kara <jack@suse.cz>
Date: Mon, 27 Feb 2023 18:32:19 +0000 (+0100)
Subject: udf: Fix lost writes in udf_adinicb_writepage()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=49854d3ccc55efd7e6873e0c39f360bdbe251c51;p=linux.git

udf: Fix lost writes in udf_adinicb_writepage()

The patch converting udf_adinicb_writepage() to avoid manually kmapping
the page used memcpy_to_page() however that copies in the wrong
direction (effectively overwriting file data with the old contents).
What we should be using is memcpy_from_page() to copy data from the page
into the inode and then mark inode dirty to store the data.

Fixes: 5cfc45321a6d ("udf: Convert udf_adinicb_writepage() to memcpy_to_page()")
Signed-off-by: Jan Kara <jack@suse.cz>
---

diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index f7a9607c2b957..facaf3a206251 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -193,7 +193,7 @@ static int udf_adinicb_writepage(struct folio *folio,
 	struct udf_inode_info *iinfo = UDF_I(inode);
 
 	BUG_ON(!PageLocked(page));
-	memcpy_to_page(page, 0, iinfo->i_data + iinfo->i_lenEAttr,
+	memcpy_from_page(iinfo->i_data + iinfo->i_lenEAttr, page, 0,
 		       i_size_read(inode));
 	unlock_page(page);
 	mark_inode_dirty(inode);