From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757844Ab3HMQ0u (ORCPT ); Tue, 13 Aug 2013 12:26:50 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:32930 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757562Ab3HMQ0r (ORCPT ); Tue, 13 Aug 2013 12:26:47 -0400 X-Authority-Analysis: v=2.0 cv=P6i4d18u c=1 sm=0 a=Sro2XwOs0tJUSHxCKfOySw==:17 a=Drc5e87SC40A:10 a=Ciwy3NGCPMMA:10 a=3X6558LbvFsA:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=meVymXHHAAAA:8 a=KGjhK52YXX0A:10 a=ojALGKljvAMA:10 a=HJjSp1d9RB5yKTmlI9kA:9 a=jeBq3FmKZ4MA:10 a=nHvdhx9J_PIOvjQ_:21 a=WGCN__9KUcDJKUas:21 a=Sro2XwOs0tJUSHxCKfOySw==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 67.255.60.225 Message-Id: <20130813155837.133377315@goodmis.org> User-Agent: quilt/0.60-1 Date: Tue, 13 Aug 2013 11:58:18 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jan Kara , Theodore Tso Subject: [84/88] ext4: fix overflow when counting used blocks on 32-bit architectures References: <20130813155654.069291373@goodmis.org> Content-Disposition: inline; filename=0084-ext4-fix-overflow-when-counting-used-blocks-on-32-bi.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.6.11.7-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Jan Kara [ Upstream commit 8af8eecc1331dbf5e8c662022272cf667e213da5 ] The arithmetics adding delalloc blocks to the number of used blocks in ext4_getattr() can easily overflow on 32-bit archs as we first multiply number of blocks by blocksize and then divide back by 512. Make the arithmetics more clever and also use proper type (unsigned long long instead of unsigned long). Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o Signed-off-by: Steven Rostedt --- fs/ext4/inode.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 72c9d8d..b65a0f8 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4385,7 +4385,7 @@ int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) { struct inode *inode; - unsigned long delalloc_blocks; + unsigned long long delalloc_blocks; inode = dentry->d_inode; generic_fillattr(inode, stat); @@ -4403,7 +4403,7 @@ int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry, delalloc_blocks = EXT4_C2B(EXT4_SB(inode->i_sb), EXT4_I(inode)->i_reserved_data_blocks); - stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9; + stat->blocks += delalloc_blocks << (inode->i_sb->s_blocksize_bits-9); return 0; } -- 1.7.10.4