From: Jan Kara <jack@suse.cz>

Date: Mon, 2 Jan 2023 20:14:47 +0100

Subject: [PATCH] udf: Do not update file length for failed writes to inline

 files

References: bsc#1012628

Patch-mainline: 6.2.3

Git-commit: 256fe4162f8b5a1625b8603ca5f7ff79725bfb47

commit 256fe4162f8b5a1625b8603ca5f7ff79725bfb47 upstream.

When write to inline file fails (or happens only partly), we still

updated length of inline data as if the whole write succeeded. Fix the

update of length of inline data to happen only if the write succeeds.

Reported-by: syzbot+0937935b993956ba28ab@syzkaller.appspotmail.com

CC: stable@vger.kernel.org

Signed-off-by: Jan Kara <jack@suse.cz>

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Jiri Slaby <jslaby@suse.cz>

---

 fs/udf/file.c | 26 ++++++++++++--------------

 1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/fs/udf/file.c b/fs/udf/file.c

index 5c659e23..8be51161 100644

--- a/fs/udf/file.c

+++ b/fs/udf/file.c

@@ -149,26 +149,24 @@ static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from)

 		goto out;

 	down_write(&iinfo->i_data_sem);

-	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {

-		loff_t end = iocb->ki_pos + iov_iter_count(from);

-

-		if (inode->i_sb->s_blocksize <

-				(udf_file_entry_alloc_offset(inode) + end)) {

-			err = udf_expand_file_adinicb(inode);

-			if (err) {

-				inode_unlock(inode);

-				udf_debug("udf_expand_adinicb: err=%d\n", err);

-				return err;

-			}

-		} else {

-			iinfo->i_lenAlloc = max(end, inode->i_size);

-			up_write(&iinfo->i_data_sem);

+	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB &&

+	    inode->i_sb->s_blocksize < (udf_file_entry_alloc_offset(inode) +

+				 iocb->ki_pos + iov_iter_count(from))) {

+		err = udf_expand_file_adinicb(inode);

+		if (err) {

+			inode_unlock(inode);

+			udf_debug("udf_expand_adinicb: err=%d\n", err);

+			return err;

 		}

 	} else

 		up_write(&iinfo->i_data_sem);

 	retval = __generic_file_write_iter(iocb, from);

 out:

+	down_write(&iinfo->i_data_sem);

+	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB && retval > 0)

+		iinfo->i_lenAlloc = inode->i_size;

+	up_write(&iinfo->i_data_sem);

 	inode_unlock(inode);

 	if (retval > 0) {

-- 

2.35.3