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authorIngo Molnar <mingo@kernel.org>2021-02-12 14:54:51 +0300
committerIngo Molnar <mingo@kernel.org>2021-02-12 14:54:58 +0300
commit62137364e3e8afcc745846c5c67cacf943149073 (patch)
tree42f2bdee6b16e383b6e0a94cb3abc62f335d721a /drivers/xen/privcmd.c
parent6c80408a8a0360fa9223b8c21c0ab8ef42e88bfe (diff)
parentdcc0b49040c70ad827a7f3d58a21b01fdb14e749 (diff)
downloadlinux-62137364e3e8afcc745846c5c67cacf943149073.tar.xz
Merge branch 'linus' into locking/core, to pick up upstream fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/xen/privcmd.c')
-rw-r--r--drivers/xen/privcmd.c25
1 files changed, 19 insertions, 6 deletions
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index b0c73c58f987..720a7b7abd46 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -717,14 +717,15 @@ static long privcmd_ioctl_restrict(struct file *file, void __user *udata)
return 0;
}
-static long privcmd_ioctl_mmap_resource(struct file *file, void __user *udata)
+static long privcmd_ioctl_mmap_resource(struct file *file,
+ struct privcmd_mmap_resource __user *udata)
{
struct privcmd_data *data = file->private_data;
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
struct privcmd_mmap_resource kdata;
xen_pfn_t *pfns = NULL;
- struct xen_mem_acquire_resource xdata;
+ struct xen_mem_acquire_resource xdata = { };
int rc;
if (copy_from_user(&kdata, udata, sizeof(kdata)))
@@ -734,6 +735,22 @@ static long privcmd_ioctl_mmap_resource(struct file *file, void __user *udata)
if (data->domid != DOMID_INVALID && data->domid != kdata.dom)
return -EPERM;
+ /* Both fields must be set or unset */
+ if (!!kdata.addr != !!kdata.num)
+ return -EINVAL;
+
+ xdata.domid = kdata.dom;
+ xdata.type = kdata.type;
+ xdata.id = kdata.id;
+
+ if (!kdata.addr && !kdata.num) {
+ /* Query the size of the resource. */
+ rc = HYPERVISOR_memory_op(XENMEM_acquire_resource, &xdata);
+ if (rc)
+ return rc;
+ return __put_user(xdata.nr_frames, &udata->num);
+ }
+
mmap_write_lock(mm);
vma = find_vma(mm, kdata.addr);
@@ -768,10 +785,6 @@ static long privcmd_ioctl_mmap_resource(struct file *file, void __user *udata)
} else
vma->vm_private_data = PRIV_VMA_LOCKED;
- memset(&xdata, 0, sizeof(xdata));
- xdata.domid = kdata.dom;
- xdata.type = kdata.type;
- xdata.id = kdata.id;
xdata.frame = kdata.idx;
xdata.nr_frames = kdata.num;
set_xen_guest_handle(xdata.frame_list, pfns);