Per USB HID spec, the buffer holding key codes should at least 3-byte long. Today's code assumes that the key codes buffer length is longer than 3-byte and unconditionally accesses the key codes buffer. It's incorrect. The patch fixes the issue by returning Device Error when the length is less than 3-byte.
Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Ruiyu Ni <ruiyu...@intel.com> Cc: Star Zeng <star.z...@intel.com> Cc: Jiewen Yao <jiewen....@intel.com> Cc: Steven Shi <steven....@intel.com> --- MdeModulePkg/Bus/Usb/UsbMouseDxe/UsbMouse.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/MdeModulePkg/Bus/Usb/UsbMouseDxe/UsbMouse.c b/MdeModulePkg/Bus/Usb/UsbMouseDxe/UsbMouse.c index 9324994975..d4bcf15929 100644 --- a/MdeModulePkg/Bus/Usb/UsbMouseDxe/UsbMouse.c +++ b/MdeModulePkg/Bus/Usb/UsbMouseDxe/UsbMouse.c @@ -811,8 +811,6 @@ OnMouseInterruptComplete ( return EFI_SUCCESS; } - UsbMouseDevice->StateChanged = TRUE; - // // Check mouse Data // USB HID Specification specifies following data format: @@ -825,6 +823,12 @@ OnMouseInterruptComplete ( // 2 0 to 7 Y displacement // 3 to n 0 to 7 Device specific (optional) // + if ((Data != NULL) && (DataLength < 3)) { + return EFI_DEVICE_ERROR; + } + + UsbMouseDevice->StateChanged = TRUE; + UsbMouseDevice->State.LeftButton = (BOOLEAN) ((*(UINT8 *) Data & BIT0) != 0); UsbMouseDevice->State.RightButton = (BOOLEAN) ((*(UINT8 *) Data & BIT1) != 0); UsbMouseDevice->State.RelativeMovementX += *((INT8 *) Data + 1); -- 2.16.1.windows.1 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel