clang-format

Problem

Control Flow Guard (CFG/CFI) protects the code flow integrity by ensuring that indirect calls are made only to vetted functions. This mitigation protects dynamically resolved function targets by instrumenting the code responsible for transferring execution control. Higher-level programming languages implement structured exception handling by managing their own code flow execution paths. As such, they are subject to code flow hijacking during runtime. Language-specific exception handling mitigation enforces execution integrity by instrumenting calls to manage execution context switching. Any deviation from the known and trusted code flow paths will cause the application to terminate. This makes malicious code less likely to execute.

Problem

Control Flow Guard (CFG/CFI) protects the code flow integrity by ensuring that indirect calls are made only to vetted functions. This mitigation protects dynamically resolved function targets by instrumenting the code responsible for transferring execution control. Function pointers that get resolved through import and delayed import address tables do not need to be monitored during application runtime. Instead, it is expected that modern programming language toolchains place those pointers in read-only memory locations. However, the delayed import functions are resolved as they are needed during runtime. To ensure the function pointers remain read-only, the operating system must be made aware if it is safe to re-protect the memory pages that hold them. Modern toolchains typically separate import data from other application regions for this very reason.