Module parent

Structs§

ChildListener: A listener for the FFI start info channel along with relevant state.
ExecEnd: An error came up while waiting on the child process to do something. It likely died, with this return code if we have one.

ExecEvent: A unified event representing something happening on the child process. Wraps nix’s WaitStatus and our custom signals so it can all be done with one match statement.
InitialCont 🔒: Whether to call ptrace::cont() immediately. Used exclusively by wait_for_signal.

PAGE_ADDR 🔒: The address of the page set to be edited, initialised to a sentinel null pointer.
PAGE_COUNT 🔒: How many consecutive pages to unprotect. 1 by default, unlikely to be set higher than 2.
PAGE_SIZE: The host pagesize, initialised to a sentinel zero value.

ArchIndependentRegs 🔒: Allows us to get common arguments from the user_regs_t across architectures. Normally this would land us ABI hell, but thankfully all of our usecases consist of functions with a small number of register-sized integer arguments. See https://man7.org/linux/man-pages/man2/syscall.2.html for sources.

capstone_disassemble 🔒: Extract the events from the given instruction.
capstone_find_events 🔒: Add the memory events from op being executed while there is a memory access at addr to acc_events. Return whether this was a memory operand.
get_disasm 🔒: Spawns a Capstone disassembler for the host architecture.
handle_segfault 🔒: Grabs the access that caused a segfault and logs it down if it’s to our memory, or kills the child and returns the appropriate error otherwise.
mempr_off^⚠: Disables protections on the page whose address is currently in PAGE_ADDR.
mempr_on^⚠: Reenables protection on the page set by PAGE_ADDR.
sv_loop: This is the main loop of the supervisor process. It runs in a separate process from the rest of Miri (but because we fork, addresses for anything created before the fork - like statics - are the same).
wait_for_signal 🔒: Waits for wait_signal. If init_cont, it will first do a ptrace::cont. We want to avoid that in some cases, like at the beginning of FFI.