CVE-2021-47523: linux kernel — Fix

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().

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-401 CWE-401

Affected Products

Vendor	Product	Versions
linux	linux_kernel	4.5 — 5.10.85
linux	linux_kernel	5.11 — 5.15.8
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/2c08271f4ed0e24633b3f81ceff61052b9d45efc https://git.kernel.org/stable/c/60a8b5a1611b4a26de4839ab9c1fc2a9cf3e17c1 https://git.kernel.org/stable/c/834d0fb978643eaf09da425de197cc16a7c2761b https://git.kernel.org/stable/c/2c08271f4ed0e24633b3f81ceff61052b9d45efc https://git.kernel.org/stable/c/60a8b5a1611b4a26de4839ab9c1fc2a9cf3e17c1 https://git.kernel.org/stable/c/834d0fb978643eaf09da425de197cc16a7c2761b

Frequently Asked Questions

What is CVE-2021-47523? +

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(). It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2021-47523? +

CVE-2021-47523 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2021-47523? +

CVE-2021-47523 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-47523? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2021-47523