imPC@ndo IT

Tracker / CVE-2022-48828

CVE-2022-48828

Critical 9.1

In the Linux kernel, the following vulnerability has been resolved: NFSD: Fix ia_size underflow iattr::ia_size is a loff_t, which is a signed 64-bit type. NFSv3 and NFSv4 both define file size as an unsigned 64-bit type. Thus there is a range of valid file size values an NFS client can send that is already larger than Linux can handle. Currently decode_fattr4() dumps a full u64 value into ia_size. If that value happens to be larger than S64_MAX, then ia_size underflows. I'm about to fix up the NFSv3 behavior as well, so let's catch the underflow in the common code path: nfsd_setattr().

Affected products and versions

linux linux_kernel
linux linux_kernel · … → 5.4.295
linux linux_kernel · 5.11 → 5.15.24
linux linux_kernel · 5.16 → 5.16.10
linux linux_kernel · 5.5 → 5.10.220

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.

References