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Date: Mon, 17 Jun 2024 17:43:10 +0200
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Michal Hocko <mhocko@suse.com>
Cc: cve@kernel.org, linux-kernel@vger.kernel.org,
	Eric Dumazet <edumazet@google.com>,
	linux-cve-announce@vger.kernel.org
Subject: Re: CVE-2024-35840: mptcp: use OPTION_MPTCP_MPJ_SYNACK in
 subflow_finish_connect()
Message-ID: <2024061750-glade-overstep-7759@gregkh>
References: <2024051756-CVE-2024-35840-99fa@gregkh>
 <ZmFtaijTs6mOpB5B@tiehlicka>
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In-Reply-To: <ZmFtaijTs6mOpB5B@tiehlicka>

On Thu, Jun 06, 2024 at 10:03:54AM +0200, Michal Hocko wrote:
> Hi,
> what is the actual security threat here? As far as I can see, the
> problem that the commit requested here addresses seems to be rather
> functional, rather than responding to an unexpected packet options with
> a reset, we actually establish a connection with some garbage parameters
> (likely unpredictable). Which is unfortunate but I do not see any
> security implications.

Sorry for the delay.  I'm pretty sure this is a data leak as the
"garbage" is coming from other kernel data, and as such, was reviewed by
us as a vulnerability.

Do you not see it as such?

thanks,

greg k-h