ACK: [SRU][J][PATCH 0/1] CVE-2026-43198

[Hui Wang]

Acked-by: Hui Wang <hui.wang at canonical.com>

On 6/23/26 21:23, Cengiz Can via kernel-team wrote:
> https://ubuntu.com/security/CVE-2026-43198
>
> [ Impact ]
>
> In tcp_v6_syn_recv_sock(), the code following the call to
> tcp_v4_syn_recv_sock() executes too late. Once tcp_v4_syn_recv_sock() returns,
> the child socket is already visible in the TCP ehash table and other CPUs can
> access it, while newinet->pinet6 still points to the listener's ipv6_pinfo.
> This race allows concurrent CPUs to operate on a partially initialized socket,
> leading to memory corruption or other undefined behavior that can be triggered
> remotely.
>
> [ Fix ]
>
> jammy: backported with AI-assisted adaptation
> bionic: backported with AI-assisted adaptation
>
> [ Test Plan ]
>
> Boot tested.
>
> [ Where Problems Could Occur ]
>
> If the fix is incorrect, regressions would surface in the TCP/IPv6 stack,
> particularly during connection establishment for IPv4-mapped IPv6 sockets,
> potentially causing incorrect socket initialization, connection failures, or
> crashes under load.
>