From: Mark Fasheh Date: Tue, 30 Jun 2015 21:42:04 +0000 (-0700) Subject: btrfs: pass unaligned length to btrfs_cmp_data() X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=207910ddeeda38fd54544d94f8c8ca5a9632cc25;p=openwrt%2Fstaging%2Fblogic.git btrfs: pass unaligned length to btrfs_cmp_data() In the case that we dedupe the tail of a file, we might expand the dedupe len out to the end of our last block. We don't want to compare data past i_size however, so pass the original length to btrfs_cmp_data(). Signed-off-by: Mark Fasheh Reviewed-by: David Sterba Signed-off-by: Chris Mason --- diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index c86b835da7a8..55504338491d 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2943,7 +2943,8 @@ static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen, goto out_unlock; } - ret = btrfs_cmp_data(src, loff, dst, dst_loff, len); + /* pass original length for comparison so we stay within i_size */ + ret = btrfs_cmp_data(src, loff, dst, dst_loff, olen); if (ret == 0) ret = btrfs_clone(src, dst, loff, olen, len, dst_loff);