Microsoft Technology Licensing, LLC

Matthew John Woolman

Mehmet Iyigun

Jason Lin

Jin Lin

Jakob Frederik Lichtenberg

Hyuk Joon Kwon

Sebastian Lerner

Andrew Meyer Kluemke

Sandeep Repaka

Swati Kanchan

Described are examples for tracking memory usage of a driver. A memory allocation request related to the driver to allocate a portion of memory for the driver can be traced in a kernel mode of an operating system. One or more associated allocation parameters can be recorded, and an allocation history of the driver over a period of time can be reported during execution of the driver and based on the one or more allocation parameters indicated by the memory allocation request.

Advanced memory tracking for kernel mode drivers

Handling a memory fault based on detecting whether a memory pointer was invalidated by a pointer authentication (PA) failure. After an access to a memory pointer causes a memory fault, detecting that the memory pointer was invalidated by a PA failure includes creating a new memory pointer by replacing reserved bits of the memory pointer with a default value, and determining that the new memory pointer corresponds to a memory address that falls within executable memory. This determination includes determining that the memory address is within an executable memory page, determining that a call instruction is stored at a prior memory address that immediately precedes the memory address, and/or determining that the memory address corresponds to a code section of an executable file. The PA failure is handled based on logging the PA failure, terminating the application program, and/or resuming execution at an instruction stored at the memory address.

Pointer authentication failure detection

Performing shadow stack functionality for a thread in an audit mode includes initiating execution of a thread at the processor. Execution of the thread includes initiating execution of executable code of an application binary as part of the thread and enabling shadow stack functionality for the thread in an audit mode. Based at least on the execution of the thread in the audit mode, at least a portion of the shadow stack is enabled to be a circular stack. In response to determining that usage of the shadow stack has reached the defined threshold, one or more currently used entries of the shadow stack are overwritten, preventing the shadow stack from overflowing.

Circular shadow stack in audit mode

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