CVE-2026-52971
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: net: ena: PHC: Fix potential use-after-free in get_timestamp Move the phc->active check and resp pointer assignment to after acquiring the spinlock. Previously, phc->active was checked without holding the lock, and resp was cached from ena_dev->phc.virt_addr before the lock was acquired. If ena_com_phc_destroy() runs between the lockless active check and the lock acquisition, it sets active=false, releases the lock, frees the DMA memory, and sets virt_addr=NULL. The get_timestamp path would then read a NULL virt_addr and dereference it. With both the active check and the pointer read under the lock, destroy cannot free the memory while get_timestamp is using it.
Severity
HIGH
CVSS score
7.8
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-06-24 17:17:07.630000
Last modified
2026-10-19 20:18:51.767000
View original CVE JSON
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"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-06-24T17:17:07.630",
"lastModified": "2026-10-19T20:18:51.767",
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ena: PHC: Fix potential use-after-free in get_timestamp\n\nMove the phc->active check and resp pointer assignment to after\nacquiring the spinlock. Previously, phc->active was checked without\nholding the lock, and resp was cached from ena_dev->phc.virt_addr\nbefore the lock was acquired.\n\nIf ena_com_phc_destroy() runs between the lockless active check and\nthe lock acquisition, it sets active=false, releases the lock, frees\nthe DMA memory, and sets virt_addr=NULL. The get_timestamp path would\nthen read a NULL virt_addr and dereference it.\n\nWith both the active check and the pointer read under the lock,\ndestroy cannot free the memory while get_timestamp is using it."
}
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