CVE-2021-47649

medium
Published 2022-11-15 · Modified 2022-11-15
CVSS v3
VIR risk
5.5

Description

In the Linux kernel, the following vulnerability has been resolved: udmabuf: validate ubuf->pagecount Syzbot has reported GPF in sg_alloc_append_table_from_pages(). The problem was in ubuf->pages == ZERO_PTR. ubuf->pagecount is calculated from arguments passed from user-space. If user creates udmabuf with list.size == 0 then ubuf->pagecount will be also equal to zero; it causes kmalloc_array() to return ZERO_PTR. Fix it by validating ubuf->pagecount before passing it to kmalloc_array().

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No vendor mitigations ingested yet for this CVE. The mitigation-content worker queues fetches as references arrive — check back in a few minutes, or see the references list below.

OS impact

OSVersionStatusFixed in
redhat rhel9fixed
suse slesaffected
debian debianbookwormfixed5.17.3-1
debian debianbullseyefixed5.10.113-1
debian debianforkyfixed5.17.3-1
debian debiansidfixed5.17.3-1
debian debiantrixiefixed5.17.3-1

References

💬 Discuss CVE-2021-47649 on VIR Community →

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.