[ Upstream commit 83c7423d1eb6806d13c521d1002cc1a012111719 ] When extending the last extent in the file within the last block, we wrongly computed the length of the last extent. This is mostly a cosmetical problem since the extent does not contain any data and the length will be fixed up by following operations but still. Fixes: 1f3868f06855 ("udf: Fix extending file within last block") Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Sasha Levin <sashal@kernel.org>