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

What is CVE-2021-47523?

CVE-2021-47523 is a medium-severity vulnerability in Linux kernel, published on 24 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.

Official 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().

Weakness: CWE-401

Which versions are affected by CVE-2021-47523?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2021-47523?

Apply the vendor's patch.

Is CVE-2021-47523 being exploited?

There is no known exploitation of CVE-2021-47523 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• How this page is made

Also known as DEBIAN-CVE-2021-47523, UBUNTU-CVE-2021-47523.