CVE-2021-47649

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A issue in the Linux kernel has been identified where the udmabuf validation of ubuf->pagecount is insufficient. This occurs when a user creates a udmabuf with list.size == 0, resulting in ubuf->pagecount being zero. This causes kmalloc array() to return ZERO PTR, leading to a general protection fault (GPF) in sg alloc append table from pages().

Recommendations For the affected Linux kernel version, validate ubuf->pagecount before passing it to kmalloc array() to prevent the GPF in sg alloc append table from pages(). At the moment, there is no information about a newer version that contains a fix for this vulnerability.