tree 959938beb9ef789e72217844d159c95604817ac5
parent 99beae6cb8f4dd5dab81a370b79c3b1085848d89
author Daniel De Graaf <dgdegra@tycho.nsa.gov> 1357167431 +0000
committer Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> 1358283666 -0500

xen/gntdev: fix unsafe vma access

In gntdev_ioctl_get_offset_for_vaddr, we need to hold mmap_sem while
calling find_vma() to avoid potentially having the result freed out from
under us.  Similarly, the MMU notifier functions need to synchronize with
gntdev_vma_close to avoid map->vma being freed during their iteration.

Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>