CVE-2025-68250 (GCVE-0-2025-68250)
Vulnerability from cvelistv5
Published
2025-12-16 14:32
Modified
2025-12-16 14:32
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: hung_task: fix warnings caused by unaligned lock pointers The blocker tracking mechanism assumes that lock pointers are at least 4-byte aligned to use their lower bits for type encoding. However, as reported by Eero Tamminen, some architectures like m68k only guarantee 2-byte alignment of 32-bit values. This breaks the assumption and causes two related WARN_ON_ONCE checks to trigger. To fix this, the runtime checks are adjusted to silently ignore any lock that is not 4-byte aligned, effectively disabling the feature in such cases and avoiding the related warnings. Thanks to Geert Uytterhoeven for bisecting!
References
Impacted products
Vendor Product Version
Linux Linux Version: e711faaafbe54a884f33b53472434063d342f6d4
Version: e711faaafbe54a884f33b53472434063d342f6d4
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nhung_task: fix warnings caused by unaligned lock pointers\n\nThe blocker tracking mechanism assumes that lock pointers are at least\n4-byte aligned to use their lower bits for type encoding.\n\nHowever, as reported by Eero Tamminen, some architectures like m68k\nonly guarantee 2-byte alignment of 32-bit values. This breaks the\nassumption and causes two related WARN_ON_ONCE checks to trigger.\n\nTo fix this, the runtime checks are adjusted to silently ignore any lock\nthat is not 4-byte aligned, effectively disabling the feature in such\ncases and avoiding the related warnings.\n\nThanks to Geert Uytterhoeven for bisecting!"
        }
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      "providerMetadata": {
        "dateUpdated": "2025-12-16T14:32:17.173Z",
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        "shortName": "Linux"
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          "url": "https://git.kernel.org/stable/c/c97513cddcfc235f2522617980838e500af21d01"
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      "title": "hung_task: fix warnings caused by unaligned lock pointers",
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    "assignerShortName": "Linux",
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    "datePublished": "2025-12-16T14:32:17.173Z",
    "dateReserved": "2025-12-16T13:41:40.266Z",
    "dateUpdated": "2025-12-16T14:32:17.173Z",
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}


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