iommu/vt-d: Fix double list_add when enabling VMD in scalable mode
CVE: CVE-2022-48916
Component: kernel
CWE: CWE-672
Severity: Moderate
CVSS v3: 5.6/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Release date: 2022-01-01T00:00:00+00:00

In the Linux kernel, the following vulnerability has been resolved:

iommu/vt-d: Fix double list_add when enabling VMD in scalable mode

When enabling VMD and IOMMU scalable mode, the following kernel panic
call trace/kernel log is shown in Eagle Stream platform (Sapphire Rapids
CPU) during booting:

pci 0000:59:00.5: Adding to iommu group 42
...
vmd 0000:59:00.5: PCI host bridge to bus 10000:80
pci 10000:80:01.0: [8086:352a] type 01 class 0x060400
pci 10000:80:01.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit]
pci 10000:80:01.0: enabling Extended Tags
pci 10000:80:01.0: PME# supported from D0 D3hot D3cold
pci 10000:80:01.0: DMAR: Setup RID2PASID failed
pci 10000:80:01.0: Failed to add to iommu group 42: -16
pci 10000:80:03.0: [8086:352b] type 01 class 0x060400
pci 10000:80:03.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit]
pci 10000:80:03.0: enabling Extended Tags
pci 10000:80:03.0: PME# supported from D0 D3hot D3cold
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:29!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.17.0-rc3+ #7
Hardware name: Lenovo ThinkSystem SR650V3/SB27A86647, BIOS ESE101Y-1.00 01/13/2022
Workqueue: events work_for_cpu_fn
RIP: 0010:__list_add_valid.cold+0x26/0x3f
Code: 9a 4a ab ff 4c 89 c1 48 c7 c7 40 0c d9 9e e8 b9 b1 fe ff 0f
      0b 48 89 f2 4c 89 c1 48 89 fe 48 c7 c7 f0 0c d9 9e e8 a2 b1
      fe ff <0f> 0b 48 89 d1 4c 89 c6 4c 89 ca 48 c7 c7 98 0c d9
      9e e8 8b b1 fe
RSP: 0000:ff5ad434865b3a40 EFLAGS: 00010246
RAX: 0000000000000058 RBX: ff4d61160b74b880 RCX: ff4d61255e1fffa8
RDX: 0000000000000000 RSI: 00000000fffeffff RDI: ffffffff9fd34f20
RBP: ff4d611d8e245c00 R08: 0000000000000000 R09: ff5ad434865b3888
R10: ff5ad434865b3880 R11: ff4d61257fdc6fe8 R12: ff4d61160b74b8a0
R13: ff4d61160b74b8a0 R14: ff4d611d8e245c10 R15: ff4d611d8001ba70
FS:  0000000000000000(0000) GS:ff4d611d5ea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ff4d611fa1401000 CR3: 0000000aa0210001 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 intel_pasid_alloc_table+0x9c/0x1d0
 dmar_insert_one_dev_info+0x423/0x540
 ? device_to_iommu+0x12d/0x2f0
 intel_iommu_attach_device+0x116/0x290
 __iommu_attach_device+0x1a/0x90
 iommu_group_add_device+0x190/0x2c0
 __iommu_probe_device+0x13e/0x250
 iommu_probe_device+0x24/0x150
 iommu_bus_notifier+0x69/0x90
 blocking_notifier_call_chain+0x5a/0x80
 device_add+0x3db/0x7b0
 ? arch_memremap_can_ram_remap+0x19/0x50
 ? memremap+0x75/0x140
 pci_device_add+0x193/0x1d0
 pci_scan_single_device+0xb9/0xf0
 pci_scan_slot+0x4c/0x110
 pci_scan_child_bus_extend+0x3a/0x290
 vmd_enable_domain.constprop.0+0x63e/0x820
 vmd_probe+0x163/0x190
 local_pci_probe+0x42/0x80
 work_for_cpu_fn+0x13/0x20
 process_one_work+0x1e2/0x3b0
 worker_thread+0x1c4/0x3a0
 ? rescuer_thread+0x370/0x370
 kthread+0xc7/0xf0
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork+0x1f/0x30
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
...
Kernel panic - not syncing: Fatal exception
Kernel Offset: 0x1ca00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
---[ end Kernel panic - not syncing: Fatal exception ]---

The following 'lspci' output shows devices '10000:80:*' are subdevices of
the VMD device 0000:59:00.5:

  $ lspci
  ...
  0000:59:00.5 RAID bus controller: Intel Corporation Volume Management Device NVMe RAID Controller (rev 20)
  ...
  10000:80:01.0 PCI bridge: Intel Corporation Device 352a (rev 03)
  10000:80:03.0 PCI bridge: Intel Corporation Device 352b (rev 03)
  10000:80:05.0 PCI bridge: Intel Corporation Device 352c (rev 03)
  10000:80:07.0 PCI bridge: Intel Corporation Device 352d (rev 03)
  10000:81:00.0 Non-Volatile memory controller: Intel Corporation NVMe Datacenter SSD [3DNAND, Beta Rock Controller]
  10000:82:00
---truncated---


Remediation: