tree 2189b2fd37cf9faf6ca930581ae0c21c5fb1ab65
parent c3d9fda688742c06e89aa1f0f8fd943fc11468cb
author Richard Weinberger <richard@nod.at> 1490863849 +0200
committer Richard Weinberger <richard@nod.at> 1492550282 +0200

ubifs: Fix O_TMPFILE corner case in ubifs_link()

It is perfectly fine to link a tmpfile back using linkat().
Since tmpfiles are created with a link count of 0 they appear
on the orphan list, upon re-linking the inode has to be removed
from the orphan list again.

Ralph faced a filesystem corruption in combination with overlayfs
due to this bug.

Cc: <stable@vger.kernel.org>
Cc: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Cc: Amir Goldstein <amir73il@gmail.com>
Reported-by: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Tested-by: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Reported-by: Amir Goldstein <amir73il@gmail.com>
Fixes: 474b93704f321 ("ubifs: Implement O_TMPFILE")
Signed-off-by: Richard Weinberger <richard@nod.at>