vulnerability

Red Hat: CVE-2025-21648: kernel: netfilter: conntrack: clamp maximum hashtable size to INT_MAX (Multiple Advisories)

Severity
6
CVSS
(AV:L/AC:L/Au:S/C:C/I:N/A:C)
Published
Jan 19, 2025
Added
Jul 9, 2025
Modified
Nov 14, 2025

Description

In the Linux kernel, the following vulnerability has been resolved:

netfilter: conntrack: clamp maximum hashtable size to INT_MAX

Use INT_MAX as maximum size for the conntrack hashtable. Otherwise, it
is possible to hit WARN_ON_ONCE in __kvmalloc_node_noprof() when
resizing hashtable because __GFP_NOWARN is unset. See:

0708a0afe291 ("mm: Consider __GFP_NOWARN flag for oversized kvmalloc() calls")

Note: hashtable resize is only possible from init_netns.

Solutions

no-fix-redhat-rpm-packageredhat-upgrade-kernelredhat-upgrade-kernel-rt
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