CVE-2022-48675

/// Technical description

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

IB/core: Fix a nested dead lock as part of ODP flow

Fix a nested dead lock as part of ODP flow by using mmput_async().

From the below call trace [1] can see that calling mmput() once we have

the umem_odp->umem_mutex locked as required by

ib_umem_odp_map_dma_and_lock() might trigger in the same task the

exit_mmap()->__mmu_notifier_release()->mlx5_ib_invalidate_range() which

may dead lock when trying to lock the same mutex.

Moving to use mmput_async() will solve the problem as the above

exit_mmap() flow will be called in other task and will be executed once

the lock will be available.

[1]

[64843.077665] task:kworker/u133:2 state:D stack: 0 pid:80906 ppid:

2 flags:0x00004000

[64843.077672] Workqueue: mlx5_ib_page_fault mlx5_ib_eqe_pf_action [mlx5_ib]

[64843.077719] Call Trace:

[64843.077722] <TASK>

[64843.077724] __schedule+0x23d/0x590

[64843.077729] schedule+0x4e/0xb0

[64843.077735] schedule_preempt_disabled

/// 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