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vfs: swap names of {do,vfs}_clone_file_range()

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Commit 031a072a0b ("vfs: call vfs_clone_file_range() under freeze
protection") created a wrapper do_clone_file_range() around
vfs_clone_file_range() moving the freeze protection to former, so
overlayfs could call the latter.

The more common vfs practice is to call do_xxx helpers from vfs_xxx
helpers, where freeze protecction is taken in the vfs_xxx helper, so
this anomality could be a source of confusion.

It seems that commit 8ede205541 ("ovl: add reflink/copyfile/dedup
support") may have fallen a victim to this confusion -
ovl_clone_file_range() calls the vfs_clone_file_range() helper in the
hope of getting freeze protection on upper fs, but in fact results in
overlayfs allowing to bypass upper fs freeze protection.

Swap the names of the two helpers to conform to common vfs practice
and call the correct helpers from overlayfs and nfsd.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This commit is contained in:
Amir Goldstein
2018-09-18 16:34:34 +03:00
committed by Miklos Szeredi
parent d9d150ae50
commit a725356b66
6 changed files with 23 additions and 20 deletions
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2
fs/overlayfs/copy_up.c
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@@ -141,7 +141,7 @@ static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len)
}
/* Try to use clone_file_range to clone up within the same fs */
error = vfs_clone_file_range(old_file, 0, new_file, 0, len);
error = do_clone_file_range(old_file, 0, new_file, 0, len);
if (!error)
goto out;
/* Couldn't clone, so now we try to copy the data */

2
fs/overlayfs/file.c
View File

@@ -461,7 +461,7 @@ static ssize_t ovl_copyfile(struct file *file_in, loff_t pos_in,
break;
case OVL_CLONE:
ret = do_clone_file_range(real_in.file, pos_in,
ret = vfs_clone_file_range(real_in.file, pos_in,
real_out.file, pos_out, len);
break;