[PATCH 2/3] Staging: hv: mousevsc: Add a check to prevent memory corruption
From: "K. Y. Srinivasan" <kys@microsoft.com>
Date: 2011-10-28 21:46:47
Also in:
lkml
Subsystem:
staging subsystem, the rest · Maintainers:
Greg Kroah-Hartman, Linus Torvalds
Add a check to prevent memory corruption. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> --- drivers/staging/hv/hv_mouse.c | 12 ++++++++++++ 1 files changed, 12 insertions(+), 0 deletions(-)
diff --git a/drivers/staging/hv/hv_mouse.c b/drivers/staging/hv/hv_mouse.c
index 7c7449b..c22f729 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));
--
1.7.4.1