CVE-2021-47649

Updated: 2025-10-22 03:30:13.405762

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().


Links NIST CIRCL RHEL Ubuntu

Severity

Severity Score
CVSS Version 2.x 0.0
CVSS Version 3.x MEDIUM 5.5

Status

OS name Project name Version Score Severity Status Errata Last updated

Statement

CentOS 8.4 ELS kernel 4.18.0 5.5 MEDIUM Ignored 2025-09-10 21:47:00 Ignored due to low severity
CentOS 8.5 ELS kernel 4.18.0 5.5 MEDIUM Ignored 2025-09-10 21:47:01 Ignored due to low severity
CentOS Stream 8 ELS kernel 4.18.0 5.5 MEDIUM Ignored 2025-05-24 02:25:29 Ignored due to low severity