git: e2d6c959b29d - stable/15 - vmm: Add PRIV_DRIVER checks for passthru ioctls

The branch stable/15 has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=e2d6c959b29d85a83a0c827b02f3303b115daf03

commit e2d6c959b29d85a83a0c827b02f3303b115daf03
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2025-10-21 17:34:29 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2025-11-04 12:46:53 +0000

    vmm: Add PRIV_DRIVER checks for passthru ioctls
    
    In preparation for allowing non-root users to create and access bhyve
    VMs, add privilege checks for ioctls which operate on passthru devices.
    
    Reviewed by:    corvink
    MFC after:      2 weeks
    Sponsored by:   The FreeBSD Foundation
    Sponsored by:   Klara, Inc.
    Differential Revision:  https://reviews.freebsd.org/D53144
    
    (cherry picked from commit e11768e94787bef2866486ba8616353716a10447)
---
 sys/amd64/vmm/vmm_dev_machdep.c | 18 +++++++++++-------
 sys/dev/vmm/vmm_dev.c           |  7 +++++++
 sys/dev/vmm/vmm_dev.h           |  1 +
 3 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/sys/amd64/vmm/vmm_dev_machdep.c b/sys/amd64/vmm/vmm_dev_machdep.c
index dfebc9dcadbf..347f739d53ec 100644
--- a/sys/amd64/vmm/vmm_dev_machdep.c
+++ b/sys/amd64/vmm/vmm_dev_machdep.c
@@ -124,12 +124,16 @@ const struct vmmdev_ioctl vmmdev_machdep_ioctls[] = {
 	VMMDEV_IOCTL(VM_SET_KERNEMU_DEV, VMMDEV_IOCTL_LOCK_ONE_VCPU),
 
 	VMMDEV_IOCTL(VM_BIND_PPTDEV,
-	    VMMDEV_IOCTL_XLOCK_MEMSEGS | VMMDEV_IOCTL_LOCK_ALL_VCPUS),
+	    VMMDEV_IOCTL_XLOCK_MEMSEGS | VMMDEV_IOCTL_LOCK_ALL_VCPUS |
+	    VMMDEV_IOCTL_PRIV_CHECK_DRIVER),
 	VMMDEV_IOCTL(VM_UNBIND_PPTDEV,
-	    VMMDEV_IOCTL_XLOCK_MEMSEGS | VMMDEV_IOCTL_LOCK_ALL_VCPUS),
+	    VMMDEV_IOCTL_XLOCK_MEMSEGS | VMMDEV_IOCTL_LOCK_ALL_VCPUS |
+	    VMMDEV_IOCTL_PRIV_CHECK_DRIVER),
 
-	VMMDEV_IOCTL(VM_MAP_PPTDEV_MMIO, VMMDEV_IOCTL_LOCK_ALL_VCPUS),
-	VMMDEV_IOCTL(VM_UNMAP_PPTDEV_MMIO, VMMDEV_IOCTL_LOCK_ALL_VCPUS),
+	VMMDEV_IOCTL(VM_MAP_PPTDEV_MMIO, VMMDEV_IOCTL_LOCK_ALL_VCPUS |
+	    VMMDEV_IOCTL_PRIV_CHECK_DRIVER),
+	VMMDEV_IOCTL(VM_UNMAP_PPTDEV_MMIO, VMMDEV_IOCTL_LOCK_ALL_VCPUS |
+	    VMMDEV_IOCTL_PRIV_CHECK_DRIVER),
 #ifdef BHYVE_SNAPSHOT
 #ifdef COMPAT_FREEBSD13
 	VMMDEV_IOCTL(VM_SNAPSHOT_REQ_13, VMMDEV_IOCTL_LOCK_ALL_VCPUS),
@@ -147,9 +151,9 @@ const struct vmmdev_ioctl vmmdev_machdep_ioctls[] = {
 
 	VMMDEV_IOCTL(VM_LAPIC_LOCAL_IRQ, VMMDEV_IOCTL_MAYBE_ALLOC_VCPU),
 
-	VMMDEV_IOCTL(VM_PPTDEV_MSI, 0),
-	VMMDEV_IOCTL(VM_PPTDEV_MSIX, 0),
-	VMMDEV_IOCTL(VM_PPTDEV_DISABLE_MSIX, 0),
+	VMMDEV_IOCTL(VM_PPTDEV_MSI, VMMDEV_IOCTL_PRIV_CHECK_DRIVER),
+	VMMDEV_IOCTL(VM_PPTDEV_MSIX, VMMDEV_IOCTL_PRIV_CHECK_DRIVER),
+	VMMDEV_IOCTL(VM_PPTDEV_DISABLE_MSIX, VMMDEV_IOCTL_PRIV_CHECK_DRIVER),
 	VMMDEV_IOCTL(VM_LAPIC_MSI, 0),
 	VMMDEV_IOCTL(VM_IOAPIC_ASSERT_IRQ, 0),
 	VMMDEV_IOCTL(VM_IOAPIC_DEASSERT_IRQ, 0),
diff --git a/sys/dev/vmm/vmm_dev.c b/sys/dev/vmm/vmm_dev.c
index 51c946f24c91..5b857a171e94 100644
--- a/sys/dev/vmm/vmm_dev.c
+++ b/sys/dev/vmm/vmm_dev.c
@@ -14,6 +14,7 @@
 #include <sys/kernel.h>
 #include <sys/malloc.h>
 #include <sys/mman.h>
+#include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/queue.h>
 #include <sys/sx.h>
@@ -454,6 +455,12 @@ vmmdev_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
 	if (ioctl == NULL)
 		return (ENOTTY);
 
+	if ((ioctl->flags & VMMDEV_IOCTL_PRIV_CHECK_DRIVER) != 0) {
+		error = priv_check(td, PRIV_DRIVER);
+		if (error != 0)
+			return (error);
+	}
+
 	if ((ioctl->flags & VMMDEV_IOCTL_XLOCK_MEMSEGS) != 0)
 		vm_xlock_memsegs(sc->vm);
 	else if ((ioctl->flags & VMMDEV_IOCTL_SLOCK_MEMSEGS) != 0)
diff --git a/sys/dev/vmm/vmm_dev.h b/sys/dev/vmm/vmm_dev.h
index 410066c49cf2..2881a7063565 100644
--- a/sys/dev/vmm/vmm_dev.h
+++ b/sys/dev/vmm/vmm_dev.h
@@ -44,6 +44,7 @@ struct vmmdev_ioctl {
 #define	VMMDEV_IOCTL_LOCK_ALL_VCPUS	0x08
 #define	VMMDEV_IOCTL_ALLOC_VCPU		0x10
 #define	VMMDEV_IOCTL_MAYBE_ALLOC_VCPU	0x20
+#define	VMMDEV_IOCTL_PRIV_CHECK_DRIVER	0x40
 	int		flags;
 };