CVE-2026-23380 (GCVE-0-2026-23380)

Vulnerability from cvelistv5 – Published: 2026-03-25 10:27 – Updated: 2026-05-11 22:05
VLAI
Title
tracing: Fix WARN_ON in tracing_buffers_mmap_close
Summary
In the Linux kernel, the following vulnerability has been resolved: tracing: Fix WARN_ON in tracing_buffers_mmap_close When a process forks, the child process copies the parent's VMAs but the user_mapped reference count is not incremented. As a result, when both the parent and child processes exit, tracing_buffers_mmap_close() is called twice. On the second call, user_mapped is already 0, causing the function to return -ENODEV and triggering a WARN_ON. Normally, this isn't an issue as the memory is mapped with VM_DONTCOPY set. But this is only a hint, and the application can call madvise(MADVISE_DOFORK) which resets the VM_DONTCOPY flag. When the application does that, it can trigger this issue on fork. Fix it by incrementing the user_mapped reference count without re-mapping the pages in the VMA's open callback.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6641 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: cf9f0f7c4c5bb45e7bb270e48bab6f7837825a64 , < 91f3e8d84c89918769e71393f839c9fefadc2580 (git)
Affected: cf9f0f7c4c5bb45e7bb270e48bab6f7837825a64 , < cdd96641b64297a2db42676f051362b76280a58b (git)
Affected: cf9f0f7c4c5bb45e7bb270e48bab6f7837825a64 , < b0f269ba6fefe9e3cb9feedcf78fcd0b633800c0 (git)
Affected: cf9f0f7c4c5bb45e7bb270e48bab6f7837825a64 , < e39bb9e02b68942f8e9359d2a3efe7d37ae6be0e (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.10
Unaffected: 0 , < 6.10 (semver)
Unaffected: 6.12.77 , ≤ 6.12.* (semver)
Unaffected: 6.18.17 , ≤ 6.18.* (semver)
Unaffected: 6.19.7 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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            "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\ntracing: Correcci\u00f3n de WARN_ON en tracing_buffers_mmap_close\n\nCuando un proceso hace fork, el proceso hijo copia los VMAs del padre pero el contador de referencias user_mapped no se incrementa. Como resultado, cuando tanto el proceso padre como el hijo terminan, tracing_buffers_mmap_close() se llama dos veces. En la segunda llamada, user_mapped ya es 0, lo que hace que la funci\u00f3n devuelva -ENODEV y active un WARN_ON.\n\nNormalmente, esto no es un problema ya que la memoria est\u00e1 mapeada con VM_DONTCOPY establecido. Pero esto es solo una sugerencia, y la aplicaci\u00f3n puede llamar a madvise(MADVISE_DOFORK) lo que restablece el flag VM_DONTCOPY. Cuando la aplicaci\u00f3n hace eso, puede activar este problema al hacer fork.\n\nSe soluciona incrementando el contador de referencias user_mapped sin remapear las p\u00e1ginas en la funci\u00f3n de callback \u0027open\u0027 del VMA."
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      "product_status:known_affected": "1",
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      "title": "kernel: tracing: Fix WARN_ON in tracing_buffers_mmap_close",
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}



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