CVE-2022-48874: misc: fastrpc: Fix use-after-free and race in fastrpc_map_find

Severity: high (CVSS 7.8 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: 2024-08-21 · updated 2026-08-04
Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix use-after-free and race in fastrpc_map_find Currently, there is a race window between the point when the mutex is unlocked in fastrpc_map_lookup and the reference count increasing (fastrpc_map_get) in fastrpc_map_find, which can also lead to use-after-free. So lets merge fastrpc_map_find into fastrpc_map_lookup which allows us to both protect the maps list by also taking the &fl->lock spinlock and the reference count, since the spinlock will be released only after. Add take_ref argument to make this suitable for all callers.

Affected products

Linux kernel: from 5.18 before 6.1.8 — fixed in 6.1.8

How to fix

Upgrade to a fixed version: Linux kernel 6.1.8. Check the vendor advisory for mitigations.

References

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