Vulnerability-Lookup

FKIE_CVE-2022-49613

Vulnerability from fkie_nvd - Published: 2025-02-26 07:01 - Updated: 2026-06-17 05:18

Severity

5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: serial: 8250: Fix PM usage_count for console handover When console is enabled, univ8250_console_setup() calls serial8250_console_setup() before .dev is set to uart_port. Therefore, it will not call pm_runtime_get_sync(). Later, when the actual driver is going to take over univ8250_console_exit() is called. As .dev is already set, serial8250_console_exit() makes pm_runtime_put_sync() call with usage count being zero triggering PM usage count warning (extra debug for univ8250_console_setup(), univ8250_console_exit(), and serial8250_register_ports()): [ 0.068987] univ8250_console_setup ttyS0 nodev [ 0.499670] printk: console [ttyS0] enabled [ 0.717955] printk: console [ttyS0] printing thread started [ 1.960163] serial8250_register_ports assigned dev for ttyS0 [ 1.976830] printk: console [ttyS0] disabled [ 1.976888] printk: console [ttyS0] printing thread stopped [ 1.977073] univ8250_console_exit ttyS0 usage:0 [ 1.977075] serial8250 serial8250: Runtime PM usage count underflow! [ 1.977429] dw-apb-uart.6: ttyS0 at MMIO 0x4010006000 (irq = 33, base_baud = 115200) is a 16550A [ 1.977812] univ8250_console_setup ttyS0 usage:2 [ 1.978167] printk: console [ttyS0] printing thread started [ 1.978203] printk: console [ttyS0] enabled To fix the issue, call pm_runtime_get_sync() in serial8250_register_ports() as soon as .dev is set for an uart_port if it has console enabled. This problem became apparent only recently because 82586a721595 ("PM: runtime: Avoid device usage count underflows") added the warning printout. I confirmed this problem also occurs with v5.18 (w/o the warning printout, obviously).

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/190ce5cdc55d1b66ea582ac2be6fd5a72e3cc486	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/5df66302f03f87ae8953785a882d78e911f00c55	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/d9cb6fabc90102f9e61fe35bd0160db88f4f53b4	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/f9b11229b79c0fb2100b5bb4628a101b1d37fbf6	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	5.19
linux	linux_kernel	5.19
linux	linux_kernel	5.19
linux	linux_kernel	5.19
linux	linux_kernel	5.19
linux	linux_kernel	5.19

JSON

To clipboard

{
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      "affectedData": [
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          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/tty/serial/8250/8250_core.c",
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          "product": "Linux",
          "programFiles": [
            "drivers/tty/serial/8250/8250_core.c",
            "drivers/tty/serial/serial_core.c",
            "include/linux/serial_core.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
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              "status": "affected",
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            },
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      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nserial: 8250: Fix PM usage_count for console handover\n\nWhen console is enabled, univ8250_console_setup() calls\nserial8250_console_setup() before .dev is set to uart_port. Therefore,\nit will not call pm_runtime_get_sync(). Later, when the actual driver\nis going to take over univ8250_console_exit() is called. As .dev is\nalready set, serial8250_console_exit() makes pm_runtime_put_sync() call\nwith usage count being zero triggering PM usage count warning\n(extra debug for univ8250_console_setup(), univ8250_console_exit(), and\nserial8250_register_ports()):\n\n[    0.068987] univ8250_console_setup ttyS0 nodev\n[    0.499670] printk: console [ttyS0] enabled\n[    0.717955] printk: console [ttyS0] printing thread started\n[    1.960163] serial8250_register_ports assigned dev for ttyS0\n[    1.976830] printk: console [ttyS0] disabled\n[    1.976888] printk: console [ttyS0] printing thread stopped\n[    1.977073] univ8250_console_exit ttyS0 usage:0\n[    1.977075] serial8250 serial8250: Runtime PM usage count underflow!\n[    1.977429] dw-apb-uart.6: ttyS0 at MMIO 0x4010006000 (irq = 33, base_baud = 115200) is a 16550A\n[    1.977812] univ8250_console_setup ttyS0 usage:2\n[    1.978167] printk: console [ttyS0] printing thread started\n[    1.978203] printk: console [ttyS0] enabled\n\nTo fix the issue, call pm_runtime_get_sync() in\nserial8250_register_ports() as soon as .dev is set for an uart_port\nif it has console enabled.\n\nThis problem became apparent only recently because 82586a721595 (\"PM:\nruntime: Avoid device usage count underflows\") added the warning\nprintout. I confirmed this problem also occurs with v5.18 (w/o the\nwarning printout, obviously)."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: serial: 8250: Se ha corregido el problema de uso de PM para la transferencia de consola. Cuando la consola est\u00e1 habilitada, univ8250_console_setup() calls serial8250_console_setup() before .dev is set to uart_port. Therefore, it will not call pm_runtime_get_sync(). Later, when the actual driver is going to take over univ8250_console_exit() is called. As .dev is already set, serial8250_console_exit() makes pm_runtime_put_sync() call with usage count being zero triggering PM usage count warning (extra debug for univ8250_console_setup(), univ8250_console_exit(), and serial8250_register_ports()): [ 0.068987] univ8250_console_setup ttyS0 nodev [ 0.499670] printk: console [ttyS0] enabled [ 0.717955] printk: console [ttyS0] printing thread started [ 1.960163] serial8250_register_ports assigned dev for ttyS0 [ 1.976830] printk: console [ttyS0] disabled [ 1.976888] printk: console [ttyS0] printing thread stopped [ 1.977073] univ8250_console_exit ttyS0 usage:0 [ 1.977075] serial8250 serial8250: Runtime PM usage count underflow! [ 1.977429] dw-apb-uart.6: ttyS0 at MMIO 0x4010006000 (irq = 33, base_baud = 115200) is a 16550A [ 1.977812] univ8250_console_setup ttyS0 usage:2 [ 1.978167] printk: console [ttyS0] printing thread started [ 1.978203] printk: console [ttyS0] enabled To fix the issue, call pm_runtime_get_sync() in serial8250_register_ports() as soon as .dev is set for an uart_port if it has console enabled. This problem became apparent only recently because 82586a721595 (\"PM: runtime: Avoid device usage count underflows\") agreg\u00f3 la impresi\u00f3n de advertencia. Confirm\u00e9 que este problema tambi\u00e9n ocurre con v5.18 (sin la impresi\u00f3n de advertencia, obviamente)."
    }
  ],
  "id": "CVE-2022-49613",
  "lastModified": "2026-06-17T05:18:37.827",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
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        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
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  "published": "2025-02-26T07:01:36.747",
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  "vulnStatus": "Analyzed",
  "weaknesses": [
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          "lang": "en",
          "value": "NVD-CWE-noinfo"
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      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2022-49613 (GCVE-0-2022-49613)

Vulnerability from cvelistv5 – Published: 2025-02-26 02:23 – Updated: 2026-05-11 19:03

Title

serial: 8250: Fix PM usage_count for console handover

Summary

Severity

No CVSS data available.

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/d9cb6fabc90102f9e…
https://git.kernel.org/stable/c/190ce5cdc55d1b66e…
https://git.kernel.org/stable/c/5df66302f03f87ae8…
https://git.kernel.org/stable/c/f9b11229b79c0fb21…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: bedb404e91bb2908d9921fc736a518a9d89525fc , < d9cb6fabc90102f9e61fe35bd0160db88f4f53b4 (git) Affected: bedb404e91bb2908d9921fc736a518a9d89525fc , < 190ce5cdc55d1b66ea582ac2be6fd5a72e3cc486 (git) Affected: bedb404e91bb2908d9921fc736a518a9d89525fc , < 5df66302f03f87ae8953785a882d78e911f00c55 (git) Affected: bedb404e91bb2908d9921fc736a518a9d89525fc , < f9b11229b79c0fb2100b5bb4628a101b1d37fbf6 (git)
Linux	Linux	Affected: 5.7 Unaffected: 0 , < 5.7 (semver) Unaffected: 5.10.132 , ≤ 5.10.* (semver) Unaffected: 5.15.56 , ≤ 5.15.* (semver) Unaffected: 5.18.13 , ≤ 5.18.* (semver) Unaffected: 5.19 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/tty/serial/8250/8250_core.c",
            "drivers/tty/serial/serial_core.c",
            "include/linux/serial_core.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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          ],
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nserial: 8250: Fix PM usage_count for console handover\n\nWhen console is enabled, univ8250_console_setup() calls\nserial8250_console_setup() before .dev is set to uart_port. Therefore,\nit will not call pm_runtime_get_sync(). Later, when the actual driver\nis going to take over univ8250_console_exit() is called. As .dev is\nalready set, serial8250_console_exit() makes pm_runtime_put_sync() call\nwith usage count being zero triggering PM usage count warning\n(extra debug for univ8250_console_setup(), univ8250_console_exit(), and\nserial8250_register_ports()):\n\n[    0.068987] univ8250_console_setup ttyS0 nodev\n[    0.499670] printk: console [ttyS0] enabled\n[    0.717955] printk: console [ttyS0] printing thread started\n[    1.960163] serial8250_register_ports assigned dev for ttyS0\n[    1.976830] printk: console [ttyS0] disabled\n[    1.976888] printk: console [ttyS0] printing thread stopped\n[    1.977073] univ8250_console_exit ttyS0 usage:0\n[    1.977075] serial8250 serial8250: Runtime PM usage count underflow!\n[    1.977429] dw-apb-uart.6: ttyS0 at MMIO 0x4010006000 (irq = 33, base_baud = 115200) is a 16550A\n[    1.977812] univ8250_console_setup ttyS0 usage:2\n[    1.978167] printk: console [ttyS0] printing thread started\n[    1.978203] printk: console [ttyS0] enabled\n\nTo fix the issue, call pm_runtime_get_sync() in\nserial8250_register_ports() as soon as .dev is set for an uart_port\nif it has console enabled.\n\nThis problem became apparent only recently because 82586a721595 (\"PM:\nruntime: Avoid device usage count underflows\") added the warning\nprintout. I confirmed this problem also occurs with v5.18 (w/o the\nwarning printout, obviously)."
        }
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      "title": "serial: 8250: Fix PM usage_count for console handover",
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    "cveId": "CVE-2022-49613",
    "datePublished": "2025-02-26T02:23:34.739Z",
    "dateReserved": "2025-02-26T02:21:30.418Z",
    "dateUpdated": "2026-05-11T19:03:20.267Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.