CVE-2021-47523: IB/hfi1: Fix leak of rcvhdrtail_dummy_kvaddr

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: 2024-05-24 · updated 2026-06-17
Weakness: CWE-401

Description

In the Linux kernel, the following vulnerability has been resolved: IB/hfi1: Fix leak of rcvhdrtail_dummy_kvaddr This buffer is currently allocated in hfi1_init(): if (reinit) ret = init_after_reset(dd); else ret = loadtime_init(dd); if (ret) goto done; /* allocate dummy tail memory for all receive contexts */ dd->rcvhdrtail_dummy_kvaddr = dma_alloc_coherent(&dd->pcidev->dev, sizeof(u64), &dd->rcvhdrtail_dummy_dma, GFP_KERNEL); if (!dd->rcvhdrtail_dummy_kvaddr) { dd_dev_err(dd, "cannot allocate dummy tail memory\n"); ret = -ENOMEM; goto done; } The reinit triggered path will overwrite the old allocation and leak it. Fix by moving the allocation to hfi1_alloc_devdata() and the deallocation to hfi1_free_devdata().

Affected products

Linux kernel: from 4.5 before 5.10.85; from 5.11 before 5.15.8; 5.16-rc1, 5.16-rc2, 5.16-rc3, 5.16-rc4 — fixed in 5.10.85, 5.15.8

How to fix

Upgrade to a fixed version: Linux kernel 5.10.85, 5.15.8. Check the vendor advisory for mitigations.

References

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