// For flags

CVE-2024-27066

virtio: packed: fix unmap leak for indirect desc table

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Public Exploits

0
*Multiple Sources

Exploited in Wild

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*KEV

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*SSVC
Descriptions

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

virtio: packed: fix unmap leak for indirect desc table

When use_dma_api and premapped are true, then the do_unmap is false.

Because the do_unmap is false, vring_unmap_extra_packed is not called by
detach_buf_packed.

if (unlikely(vq->do_unmap)) {
curr = id;
for (i = 0; i < state->num; i++) {
vring_unmap_extra_packed(vq,
&vq->packed.desc_extra[curr]);
curr = vq->packed.desc_extra[curr].next;
}
}

So the indirect desc table is not unmapped. This causes the unmap leak.

So here, we check vq->use_dma_api instead. Synchronously, dma info is
updated based on use_dma_api judgment

This bug does not occur, because no driver use the premapped with
indirect.

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: virtio: empaquetado: corrige la fuga de desasignación para la tabla desc indirecta Cuando use_dma_api y premapped son verdaderos, entonces do_unmap es falso. Debido a que do_unmap es falso, detach_buf_packed no llama a vring_unmap_extra_packed. if (improbable(vq-&gt;do_unmap)) { curr = id; for (i = 0; i &lt; estado-&gt;num; i++) { vring_unmap_extra_packed(vq, &amp;vq-&gt;packed.desc_extra[curr]); curr = vq-&gt;packed.desc_extra[curr].next; } } Por lo tanto, la tabla de descripción indirecta no está desasignada. Esto provoca la fuga de desasignación. Así que aquí marcamos vq-&gt;use_dma_api en su lugar. Sincrónicamente, la información de dma se actualiza según el criterio use_dma_api. Este error no ocurre porque ningún controlador utiliza el preasignado con indirecto.

*Credits: N/A
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* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-02-19 CVE Reserved
  • 2024-05-01 CVE Published
  • 2024-05-02 EPSS Updated
  • 2024-12-19 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.6 < 6.6.23
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.6 < 6.6.23"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.6 < 6.7.11
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.6 < 6.7.11"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.6 < 6.8.2
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.6 < 6.8.2"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.6 < 6.9
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.6 < 6.9"
en
Affected