Commit 58617c76 authored Oct 16, 2017 by Jan Kara Committed by Greg Kroah-Hartman Dec 20, 2017

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>

parent cae8f234

fs/udf/super.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -706,7 +706,7 @@ static loff_t udf_check_vsd(struct super_block *sb)
		else
		sectorsize = sb->s_blocksize;

		sector += (sbi->s_session << sb->s_blocksize_bits);
		sector += (((loff_t)sbi->s_session) << sb->s_blocksize_bits);

		udf_debug("Starting at sector %u (%ld byte sectors)\n",
		(unsigned int)(sector >> sb->s_blocksize_bits),