f051ec6463
See https://github.com/golang/go/issues/19367 for rationale. Note that the upstream decision arrived at in that thread, while useful for some of our use cases, doesn't account for all of our SliceHeader use cases (we often use SliceHeader to extract pointers from slices in a way that avoids bounds checking and/or handles nil slices correctly) and also doesn't exist yet. PiperOrigin-RevId: 358071574 |
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| .. | ||
| BUILD | ||
| README.md | ||
| access_type.go | ||
| addr.go | ||
| addr_range_seq_test.go | ||
| addr_range_seq_unsafe.go | ||
| bytes_io.go | ||
| bytes_io_unsafe.go | ||
| usermem.go | ||
| usermem_arm64.go | ||
| usermem_test.go | ||
| usermem_x86.go | ||
README.md
This package defines primitives for sentry access to application memory.
Major types:
-
The
IOinterface represents a virtual address space and provides I/O methods on that address space.IOis the lowest-level primitive. The primary implementation of theIOinterface ismm.MemoryManager. -
IOSequencerepresents a collection of individually-contiguous address ranges in aIOthat is operated on sequentially, analogous to Linux'sstruct iov_iter.
Major usage patterns:
-
Access to a task's virtual memory, subject to the application's memory protections and while running on that task's goroutine, from a context that is at or above the level of the
kernelpackage (e.g. most syscall implementations insyscalls/linux); use thekernel.Task.Copy*wrappers defined inkernel/task_usermem.go. -
Access to a task's virtual memory, from a context that is at or above the level of the
kernelpackage, but where any of the above constraints does not hold (e.g.PTRACE_POKEDATA, which ignores application memory protections); obtain the task'smm.MemoryManagerby callingkernel.Task.MemoryManager, and call itsIOmethods directly. -
Access to a task's virtual memory, from a context that is below the level of the
kernelpackage (e.g. filesystem I/O); clients must pass I/O arguments from higher layers, usually in the form of anIOSequence. Thekernel.Task.SingleIOSequenceandkernel.Task.IovecsIOSequencefunctions inkernel/task_usermem.goare convenience functions for doing so.