From 59d1d2e8e1e7c50d2657d5e4812b53f71f507968 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Thu, 9 Jul 2020 14:08:52 +0200
Subject: [PATCH] virt: vbox: Fix guest capabilities mask check
Git-commit: 59d1d2e8e1e7c50d2657d5e4812b53f71f507968
Patch-mainline: v5.8-rc6
References: git-fixes
Check the passed in capabilities against VMMDEV_GUEST_CAPABILITIES_MASK
instead of against VMMDEV_EVENT_VALID_EVENT_MASK.
This tightens the allowed mask from 0x7ff to 0x7.
Fixes: 0ba002bc4393 ("virt: Add vboxguest driver for Virtual Box Guest integration")
Cc: stable@vger.kernel.org
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200709120858.63928-3-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/virt/vboxguest/vboxguest_core.c | 2 +-
drivers/virt/vboxguest/vmmdev.h | 2 ++
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/virt/vboxguest/vboxguest_core.c b/drivers/virt/vboxguest/vboxguest_core.c
index 8fab04e76c14..18ebd7a6af98 100644
--- a/drivers/virt/vboxguest/vboxguest_core.c
+++ b/drivers/virt/vboxguest/vboxguest_core.c
@@ -1444,7 +1444,7 @@ static int vbg_ioctl_change_guest_capabilities(struct vbg_dev *gdev,
or_mask = caps->u.in.or_mask;
not_mask = caps->u.in.not_mask;
- if ((or_mask | not_mask) & ~VMMDEV_EVENT_VALID_EVENT_MASK)
+ if ((or_mask | not_mask) & ~VMMDEV_GUEST_CAPABILITIES_MASK)
return -EINVAL;
ret = vbg_set_session_capabilities(gdev, session, or_mask, not_mask,
diff --git a/drivers/virt/vboxguest/vmmdev.h b/drivers/virt/vboxguest/vmmdev.h
index 6337b8d75d96..21f408120e3f 100644
--- a/drivers/virt/vboxguest/vmmdev.h
+++ b/drivers/virt/vboxguest/vmmdev.h
@@ -206,6 +206,8 @@ VMMDEV_ASSERT_SIZE(vmmdev_mask, 24 + 8);
* not.
*/
#define VMMDEV_GUEST_SUPPORTS_GRAPHICS BIT(2)
+/* The mask of valid capabilities, for sanity checking. */
+#define VMMDEV_GUEST_CAPABILITIES_MASK 0x00000007U
/** struct vmmdev_hypervisorinfo - Hypervisor info structure. */
struct vmmdev_hypervisorinfo {
--
2.16.4