udf: Avoid overflow when session starts at large offset


[ Upstream commit abdc0eb06964fe1d2fea6dd1391b734d0590365d ]

When session starts beyond offset 2^31 the arithmetics in
udf_check_vsd() would overflow. Make sure the computation is done in
large enough type.

Reported-by: Cezary Sliwa <sliwa@ifpan.edu.pl>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed