Vulnerability-Lookup

GHSA-3CF6-344V-4FMG

Vulnerability from github – Published: 2024-07-12 15:31 – Updated: 2025-11-04 00:30

Details

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

tty: add the option to have a tty reject a new ldisc

... and use it to limit the virtual terminals to just N_TTY. They are kind of special, and in particular, the "con_write()" routine violates the "writes cannot sleep" rule that some ldiscs rely on.

This avoids the

BUG: sleeping function called from invalid context at kernel/printk/printk.c:2659

when N_GSM has been attached to a virtual console, and gsmld_write() calls con_write() while holding a spinlock, and con_write() then tries to get the console lock.

Severity ?

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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  "affected": [],
  "aliases": [
    "CVE-2024-40966"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-07-12T13:15:18Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ntty: add the option to have a tty reject a new ldisc\n\n... and use it to limit the virtual terminals to just N_TTY.  They are\nkind of special, and in particular, the \"con_write()\" routine violates\nthe \"writes cannot sleep\" rule that some ldiscs rely on.\n\nThis avoids the\n\n   BUG: sleeping function called from invalid context at kernel/printk/printk.c:2659\n\nwhen N_GSM has been attached to a virtual console, and gsmld_write()\ncalls con_write() while holding a spinlock, and con_write() then tries\nto get the console lock.",
  "id": "GHSA-3cf6-344v-4fmg",
  "modified": "2025-11-04T00:30:56Z",
  "published": "2024-07-12T15:31:28Z",
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CVE-2024-40966 (GCVE-0-2024-40966)

Vulnerability from cvelistv5 – Published: 2024-07-12 12:32 – Updated: 2026-01-05 10:36

Title

tty: add the option to have a tty reject a new ldisc

Summary

In the Linux kernel, the following vulnerability has been resolved: tty: add the option to have a tty reject a new ldisc ... and use it to limit the virtual terminals to just N_TTY. They are kind of special, and in particular, the "con_write()" routine violates the "writes cannot sleep" rule that some ldiscs rely on. This avoids the BUG: sleeping function called from invalid context at kernel/printk/printk.c:2659 when N_GSM has been attached to a virtual console, and gsmld_write() calls con_write() while holding a spinlock, and con_write() then tries to get the console lock.

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/3c6332f3bb1578b5b…
	https://git.kernel.org/stable/c/287b569a5b914903b…
	https://git.kernel.org/stable/c/5920ac19964f9e201…
	https://git.kernel.org/stable/c/6bd23e0c2bb6c65d4…

Impacted products

Vendor

Product

Version

Linux

Affected: e1eaea46bb4020b38a141b84f88565d4603f8dd0 , < 3c6332f3bb1578b5b10ac2561247b1d6272ae937 (git)
Affected: e1eaea46bb4020b38a141b84f88565d4603f8dd0 , < 287b569a5b914903ba7c438a3c0dbc3410ebb409 (git)
Affected: e1eaea46bb4020b38a141b84f88565d4603f8dd0 , < 5920ac19964f9e20181f63b410d9200ddbf8dc86 (git)
Affected: e1eaea46bb4020b38a141b84f88565d4603f8dd0 , < 6bd23e0c2bb6c65d4f5754d1456bc9a4427fc59b (git)

Linux

Affected: 2.6.35
Unaffected: 0 , < 2.6.35 (semver)
Unaffected: 6.1.96 , ≤ 6.1.* (semver)
Unaffected: 6.6.36 , ≤ 6.6.* (semver)
Unaffected: 6.9.7 , ≤ 6.9.* (semver)
Unaffected: 6.10 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

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Sightings

Author	Source	Type	Date

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.

Action not permitted

GHSA-3CF6-344V-4FMG

CVE-2024-40966 (GCVE-0-2024-40966)

Tags

Sightings

Nomenclature