From f31fdf510531333dea95f0a92e6eaa1c3a7541e2 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Sun, 8 Mar 2009 04:10:00 -0700 Subject: xen/privcmd: make sure vma is ours before doing anything to it Test vma->vm_ops is our operations to make sure we created it. We don't want to stomp on other random vmas. [ Impact: bugfix; prevent ioctl from affecting other mappings ] Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/xenfs/privcmd.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/xen/xenfs') diff --git a/drivers/xen/xenfs/privcmd.c b/drivers/xen/xenfs/privcmd.c index 6b602f505363..80526afd3063 100644 --- a/drivers/xen/xenfs/privcmd.c +++ b/drivers/xen/xenfs/privcmd.c @@ -310,6 +310,8 @@ static int mmap_return_errors(void *data, void *state) return 0; } +static struct vm_operations_struct privcmd_vm_ops; + static long privcmd_ioctl_mmap_batch(void __user *udata) { int ret; @@ -341,6 +343,7 @@ static long privcmd_ioctl_mmap_batch(void __user *udata) vma = find_vma(mm, m.addr); ret = -EINVAL; if (!vma || + vma->vm_ops != &privcmd_vm_ops || (m.addr != vma->vm_start) || ((m.addr + (nr_pages << PAGE_SHIFT)) != vma->vm_end) || !privcmd_enforce_singleshot_mapping(vma)) { -- cgit v1.2.3