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Tsirkin" To: Guanglei Zhu Cc: amit@kernel.org, virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, liuc63@xiaopeng.com Subject: Re: [PATCH] virtio: console: check the control packet size before parsing it Message-ID: <20261103062747-mutt-send-email-mst@kernel.org> References: <20261103043238-mutt-send-email-mst@kernel.org> <20261103111734.472283-1-zhugl3@xiaopeng.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261103111734.472283-1-zhugl3@xiaopeng.com> On Tue, Nov 03, 2026 at 07:17:34PM +0800, Guanglei Zhu wrote: > You are right, the impact statement does not hold up: the reused > buffer still contains a previously valid control message, Not always, the buffers are allocated with GFP_KERNEL on the 1st pass. > so a short > packet makes the driver parse stale - not attacker-controlled - data, Who is the attacker here the device? it is absolutely controlling all of virtio_console_control. > and that is not worth carrying an extra check for. Please drop this > patch. > > Sorry for the noise, and thanks for the review. I ask that you please think critically not just go back and forth on it like an LLM. -- MST