CVE-2023-52633 um: time-travel: fix time corruption

2024-04-0206:49:11

Linux

www.cve.org

linux kernel vulnerability

time-travel mode

time corruption

interrupts

time travel time

adjustment

security

cve-2023-52633

AI Score

7.6

Confidence

High

EPSS

Percentile

15.5%

JSON

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

um: time-travel: fix time corruption

In ‘basic’ time-travel mode (without =inf-cpu or =ext), we
still get timer interrupts. These can happen at arbitrary
points in time, i.e. while in timer_read(), which pushes
time forward just a little bit. Then, if we happen to get
the interrupt after calculating the new time to push to,
but before actually finishing that, the interrupt will set
the time to a value that’s incompatible with the forward,
and we’ll crash because time goes backwards when we do the
forwarding.

Fix this by reading the time_travel_time, calculating the
adjustment, and doing the adjustment all with interrupts
disabled.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "arch/um/kernel/time.c"
    ],
    "versions": [
      {
        "version": "1da177e4c3f4",
        "lessThan": "0c7478a2da3f",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "4f7dad73df4c",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "de3e9d8e8d1a",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "b427f55e9d41",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "abe4eaa8618b",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "arch/um/kernel/time.c"
    ],
    "versions": [
      {
        "version": "5.15.149",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.77",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.16",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.7.4",
        "lessThanOrEqual": "6.7.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.8",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]