On Wed, Feb 26, 2025 at 10:55:09AM -0800, Suren Baghdasaryan wrote: > Current implementation of move_pages_pte() copies source and destination > PTEs in order to detect concurrent changes to PTEs involved in the move. > However these copies are also used to unmap the PTEs, which will fail if > CONFIG_HIGHPTE is enabled because the copies are allocated on the stack. > Fix this by using the actual PTEs which were kmap()ed. > > Fixes: adef440691ba ("userfaultfd: UFFDIO_MOVE uABI") > Reported-by: Peter Xu <peterx@xxxxxxxxxx> > Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Peter Xu <peterx@xxxxxxxxxx> -- Peter Xu