Commit d9d150ae authored Sep 18, 2018 by Amir Goldstein Committed by Miklos Szeredi Sep 24, 2018

ovl: fix freeze protection bypass in ovl_clone_file_range()



Tested by doing clone on overlayfs while upper xfs+reflink is frozen:

  xfs_io -f /ovl/y
                             fsfreeze -f /xfs
  xfs_io> reflink /ovl/x

Before the fix xfs_io enters xfs_reflink_remap_range() and blocks
in xfs_trans_alloc(). After the fix, xfs_io blocks outside xfs code
in ovl_clone_file_range().

Fixes: 8ede2055 ("ovl: add reflink/copyfile/dedup support")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

parent 898cc19d

fs/overlayfs/file.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -461,7 +461,7 @@ static ssize_t ovl_copyfile(struct file *file_in, loff_t pos_in,
		break;

		case OVL_CLONE:
		ret = vfs_clone_file_range(real_in.file, pos_in,
		ret = do_clone_file_range(real_in.file, pos_in,
		real_out.file, pos_out, len);
		break;

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