From 226383751ff3ce67a648653e8bfe0842f36bbf96 Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Fri, 28 Oct 2011 15:11:27 -0700 Subject: [PATCH] Staging: hv: mousevsc: Add a check to prevent memory corruption Add a check to prevent memory corruption. Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- drivers/staging/hv/hv_mouse.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/staging/hv/hv_mouse.c b/drivers/staging/hv/hv_mouse.c index 7c7449bb5cf1..c22f729155fc 100644 --- a/drivers/staging/hv/hv_mouse.c +++ b/drivers/staging/hv/hv_mouse.c @@ -274,6 +274,18 @@ static void mousevsc_on_receive(struct hv_device *device, switch (hid_msg->header.type) { case SYNTH_HID_PROTOCOL_RESPONSE: + /* + * While it will be impossible for us to protect against + * malicious/buggy hypervisor/host, add a check here to + * ensure we don't corrupt memory. + */ + if ((pipe_msg->size + sizeof(struct pipe_prt_msg) + - sizeof(unsigned char)) + > sizeof(struct mousevsc_prt_msg)) { + WARN_ON(1); + break; + } + memcpy(&input_dev->protocol_resp, pipe_msg, pipe_msg->size + sizeof(struct pipe_prt_msg) - sizeof(unsigned char)); -- 2.30.2