CVE-2023-52484 iommu/arm-smmu-v3: Fix soft lockup triggered by arm_smmu_mm_invalidate_range

2024-02-2905:43:14

Linux

github.com

linux kernel vulnerability

soft lockup fix

arm-smmu-v3

sva case

cmdq_max_tlbi_ops

vulnerability resolution

smmu issue

cpu mmu fix

6.9 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

15.7%

JSON

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

iommu/arm-smmu-v3: Fix soft lockup triggered by arm_smmu_mm_invalidate_range

When running an SVA case, the following soft lockup is triggered:

watchdog: BUG: soft lockup - CPU#244 stuck for 26s!
pstate: 83400009 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=–)
pc : arm_smmu_cmdq_issue_cmdlist+0x178/0xa50
lr : arm_smmu_cmdq_issue_cmdlist+0x150/0xa50
sp : ffff8000d83ef290
x29: ffff8000d83ef290 x28: 000000003b9aca00 x27: 0000000000000000
x26: ffff8000d83ef3c0 x25: da86c0812194a0e8 x24: 0000000000000000
x23: 0000000000000040 x22: ffff8000d83ef340 x21: ffff0000c63980c0
x20: 0000000000000001 x19: ffff0000c6398080 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: ffff3000b4a3bbb0
x14: ffff3000b4a30888 x13: ffff3000b4a3cf60 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000000 x9 : ffffc08120e4d6bc
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000048cfa
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 000000000000000a
x2 : 0000000080000000 x1 : 0000000000000000 x0 : 0000000000000001
Call trace:
arm_smmu_cmdq_issue_cmdlist+0x178/0xa50
__arm_smmu_tlb_inv_range+0x118/0x254
arm_smmu_tlb_inv_range_asid+0x6c/0x130
arm_smmu_mm_invalidate_range+0xa0/0xa4
__mmu_notifier_invalidate_range_end+0x88/0x120
unmap_vmas+0x194/0x1e0
unmap_region+0xb4/0x144
do_mas_align_munmap+0x290/0x490
do_mas_munmap+0xbc/0x124
__vm_munmap+0xa8/0x19c
__arm64_sys_munmap+0x28/0x50
invoke_syscall+0x78/0x11c
el0_svc_common.constprop.0+0x58/0x1c0
do_el0_svc+0x34/0x60
el0_svc+0x2c/0xd4
el0t_64_sync_handler+0x114/0x140
el0t_64_sync+0x1a4/0x1a8

Note that since 6.6-rc1 the arm_smmu_mm_invalidate_range above is renamed
to “arm_smmu_mm_arch_invalidate_secondary_tlbs”, yet the problem remains.

The commit 06ff87bae8d3 (“arm64: mm: remove unused functions and variable
protoypes”) fixed a similar lockup on the CPU MMU side. Yet, it can occur
to SMMU too, since arm_smmu_mm_arch_invalidate_secondary_tlbs() is called
typically next to MMU tlb flush function, e.g.
tlb_flush_mmu_tlbonly {
tlb_flush {
__flush_tlb_range {
// check MAX_TLBI_OPS
}
}
mmu_notifier_arch_invalidate_secondary_tlbs {
arm_smmu_mm_arch_invalidate_secondary_tlbs {
// does not check MAX_TLBI_OPS
}
}
}

Clone a CMDQ_MAX_TLBI_OPS from the MAX_TLBI_OPS in tlbflush.h, since in an
SVA case SMMU uses the CPU page table, so it makes sense to align with the
tlbflush code. Then, replace per-page TLBI commands with a single per-asid
TLBI command, if the request size hits this threshold.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c"
    ],
    "versions": [
      {
        "version": "1da177e4c3f4",
        "lessThan": "f5a604757aa8",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "f90f4c562003",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "3283a1bce9bb",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "d5afb4b47e13",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c"
    ],
    "versions": [
      {
        "version": "5.15.134",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.56",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.5.6",
        "lessThanOrEqual": "6.5.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]