CVE-2023-52615: hwrng: core - Fix page fault dead lock on mmap-ed hwrng

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-03-18 · updated 2026-06-17
Weakness: CWE-667

Description

In the Linux kernel, the following vulnerability has been resolved: hwrng: core - Fix page fault dead lock on mmap-ed hwrng There is a dead-lock in the hwrng device read path. This triggers when the user reads from /dev/hwrng into memory also mmap-ed from /dev/hwrng. The resulting page fault triggers a recursive read which then dead-locks. Fix this by using a stack buffer when calling copy_to_user.

Affected products

Linux kernel: from 2.6.33 before 4.19.307; from 4.20 before 5.4.269; from 5.5 before 5.10.210; from 5.11 before 5.15.149; from 5.16 before 6.1.76; from 6.2 before 6.6.15 — fixed in 4.19.307, 5.10.210, 5.15.149, 5.4.269, 6.1.76, 6.6.15

How to fix

Upgrade to a fixed version: Linux kernel 4.19.307, 5.10.210, 5.15.149, 5.4.269. Check the vendor advisory for mitigations.

References

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