CVE-2025-39816 (GCVE-0-2025-39816)
Vulnerability from cvelistv5
Published
2025-09-16 13:00
Modified
2025-09-25 09:49
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: io_uring/kbuf: always use READ_ONCE() to read ring provided buffer lengths Since the buffers are mapped from userspace, it is prudent to use READ_ONCE() to read the value into a local variable, and use that for any other actions taken. Having a stable read of the buffer length avoids worrying about it changing after checking, or being read multiple times. Similarly, the buffer may well change in between it being picked and being committed. Ensure the looping for incremental ring buffer commit stops if it hits a zero sized buffer, as no further progress can be made at that point.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/390a61d284e1ced088d43928dfcf6f86fffdd780
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/695673eb5711ee5eb1769481cf1503714716a7d1
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/98b6fa62c84f2e129161e976a5b9b3cb4ccd117b
Impacted products
Vendor Product Version
Linux Linux Version: ae98dbf43d755b4e111fcd086e53939bef3e9a1a
Version: ae98dbf43d755b4e111fcd086e53939bef3e9a1a
Version: ae98dbf43d755b4e111fcd086e53939bef3e9a1a
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   Linux Linux Version: 6.12
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          "programFiles": [
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        "dateUpdated": "2025-09-25T09:49:12.144Z",
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    "datePublished": "2025-09-16T13:00:17.026Z",
    "dateReserved": "2025-04-16T07:20:57.138Z",
    "dateUpdated": "2025-09-25T09:49:12.144Z",
    "state": "PUBLISHED"
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  }
}


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