From 2a6b8daedaf3682bed3fc1d4e2390491f6e19c49 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Fri, 19 Nov 2010 01:36:10 +0000 Subject: [PATCH] btrfs: Check if dest_offset is block-size aligned before cloning file We've done the check for src_offset and src_length, and We should also check dest_offset, otherwise we'll corrupt the destination file: (After cloning file1 to file2 with unaligned dest_offset) # cat /mnt/file2 cat: /mnt/file2: Input/output error Signed-off-by: Li Zefan Signed-off-by: Chris Mason --- fs/btrfs/ioctl.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 463d91b4dd3a..81b47bd8a55a 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1669,12 +1669,11 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, olen = len = src->i_size - off; /* if we extend to eof, continue to block boundary */ if (off + len == src->i_size) - len = ((src->i_size + bs-1) & ~(bs-1)) - - off; + len = ALIGN(src->i_size, bs) - off; /* verify the end result is block aligned */ - if ((off & (bs-1)) || - ((off + len) & (bs-1))) + if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || + !IS_ALIGNED(destoff, bs)) goto out_unlock; /* do any pending delalloc/csum calc on src, one way or -- 2.20.1