Tracker / CVE-2021-47649
CVE-2021-47649
Medium 5.5
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().
Affected products and versions
| linux | linux_kernel · 4.20 → 5.4.189 |
|---|---|
| linux | linux_kernel · 5.11 → 5.15.33 |
| linux | linux_kernel · 5.16 → 5.16.19 |
| linux | linux_kernel · 5.17 → 5.17.2 |
| linux | linux_kernel · 5.5 → 5.10.110 |
Analysis
This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.