From: Theodore Ts'o Subject: [PATCH 3/4] ext4: fix data offset overflow in ext4_xattr_fiemap() on 32-bit archs Date: Tue, 9 Jul 2013 10:39:31 -0400 Message-ID: <1373380772-16803-3-git-send-email-tytso@mit.edu> References: <20130709143855.GF6000@thunk.org> <1373380772-16803-1-git-send-email-tytso@mit.edu> Cc: Ext4 Developers List , Jan Kara , Theodore Ts'o To: stable@vger.kernel.org Return-path: In-Reply-To: <1373380772-16803-1-git-send-email-tytso@mit.edu> Sender: stable-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org From: Jan Kara On 32-bit architectures with 32-bit sector_t computation of data offset in ext4_xattr_fiemap() can overflow resulting in reporting bogus data location. Fix the problem by typing block number to proper type before shifting. Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o --- fs/ext4/extents.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 214e68a..299ee9d 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4679,7 +4679,7 @@ static int ext4_xattr_fiemap(struct inode *inode, error = ext4_get_inode_loc(inode, &iloc); if (error) return error; - physical = iloc.bh->b_blocknr << blockbits; + physical = (__u64)iloc.bh->b_blocknr << blockbits; offset = EXT4_GOOD_OLD_INODE_SIZE + EXT4_I(inode)->i_extra_isize; physical += offset; @@ -4687,7 +4687,7 @@ static int ext4_xattr_fiemap(struct inode *inode, flags |= FIEMAP_EXTENT_DATA_INLINE; brelse(iloc.bh); } else { /* external block */ - physical = EXT4_I(inode)->i_file_acl << blockbits; + physical = (__u64)EXT4_I(inode)->i_file_acl << blockbits; length = inode->i_sb->s_blocksize; } -- 1.7.12.rc0.22.gcdd159b