CVE-2024-47143

/// Technical description

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

dma-debug: fix a possible deadlock on radix_lock

radix_lock() shouldn't be held while holding dma_hash_entry[idx].lock

otherwise, there's a possible deadlock scenario when

dma debug API is called holding rq_lock():

CPU0 CPU1 CPU2

dma_free_attrs()

check_unmap() add_dma_entry() __schedule() //out

(A) rq_lock()

get_hash_bucket()

(A) dma_entry_hash

check_sync()

(A) radix_lock() (W) dma_entry_hash

dma_entry_free()

(W) radix_lock()

// CPU2's one

(W) rq_lock()

CPU1 situation can happen when it extending radix tree and

it tries to wake up kswapd via wake_all_kswapd().

CPU2 situation can happen while perf_event_task_sched_out()

(i.e. dma sync operation is called while deleting perf_event

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References