CVE-2022-48867 dmaengine: idxd: Prevent use after free on completion memory

2024-08-2106:09:57

Linux

www.cve.org

linux kernel

cve-2022-48867

dmaengine

idxd

use after free

vulnerability

memory

completion

fix

page fault

driver unload

descriptor

address

flush

interrupt.

EPSS

Percentile

9.5%

JSON

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

dmaengine: idxd: Prevent use after free on completion memory

On driver unload any pending descriptors are flushed at the
time the interrupt is freed:
idxd_dmaengine_drv_remove() ->
drv_disable_wq() ->
idxd_wq_free_irq() ->
idxd_flush_pending_descs().

If there are any descriptors present that need to be flushed this
flow triggers a “not present” page fault as below:

BUG: unable to handle page fault for address: ff391c97c70c9040
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page

The address that triggers the fault is the address of the
descriptor that was freed moments earlier via:
drv_disable_wq()->idxd_wq_free_resources()

Fix the use after free by freeing the descriptors after any possible
usage. This is done after idxd_wq_reset() to ensure that the memory
remains accessible during possible completion writes by the device.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/dma/idxd/device.c"
    ],
    "versions": [
      {
        "version": "63c14ae6c161",
        "lessThan": "b9e8e3fcfec6",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "63c14ae6c161",
        "lessThan": "1beeec45f9ac",
        "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/dma/idxd/device.c"
    ],
    "versions": [
      {
        "version": "5.19",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.19",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.8",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.2",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]