From: Jan Kara Date: Mon, 16 May 2016 15:17:04 +0000 (+0200) Subject: ext2: Fix block zeroing in ext2_get_blocks() for DAX X-Git-Tag: v4.7-rc1~38^2~17 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=9b6cd5f76d60b563d75e55e432e03ed134761432;p=karo-tx-linux.git ext2: Fix block zeroing in ext2_get_blocks() for DAX When zeroing allocated blocks for DAX, we accidentally zeroed only the first allocated block instead of all of them. So far this problem is hidden by the fact that page faults always need only a single block and DAX write code zeroes blocks again. But the zeroing in DAX code is racy and needs to be removed so fix the zeroing in ext2 to zero all allocated blocks. Reported-by: Ross Zwisler Signed-off-by: Jan Kara Signed-off-by: Vishal Verma --- diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index 6bd58e6ff038..038d0ed5f565 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -740,7 +740,7 @@ static int ext2_get_blocks(struct inode *inode, err = dax_clear_sectors(inode->i_sb->s_bdev, le32_to_cpu(chain[depth-1].key) << (inode->i_blkbits - 9), - 1 << inode->i_blkbits); + count << inode->i_blkbits); if (err) { mutex_unlock(&ei->truncate_mutex); goto cleanup;