go
/
gvisor
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
gvisor/pkg/sentry/usermem
History
Michael Pratt 4d52a55201 Change copyright notice to "The gVisor Authors" 
Based on the guidelines at
https://opensource.google.com/docs/releasing/authors/.

1. $ rg -l "Google LLC" | xargs sed -i 's/Google LLC.*/The gVisor Authors./'
2. Manual fixup of "Google Inc" references.
3. Add AUTHORS file. Authors may request to be added to this file.
4. Point netstack AUTHORS to gVisor AUTHORS. Drop CONTRIBUTORS.

Fixes #209

PiperOrigin-RevId: 245823212
Change-Id: I64530b24ad021a7d683137459cafc510f5ee1de9
 		2019-04-29 14:26:23 -07:00
..
BUILD Convert []byte to string without copying in usermem.CopyStringIn. 2019-03-27 10:46:28 -07:00
README.md Format documentation 2018-07-12 10:37:21 -07:00
access_type.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00
addr.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00
addr_range_seq_test.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00
addr_range_seq_unsafe.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00
bytes_io.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00
bytes_io_unsafe.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00
usermem.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00
usermem_arm64.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00
usermem_test.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00
usermem_unsafe.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00
usermem_x86.go Change copyright notice to "The gVisor Authors" 2019-04-29 14:26:23 -07:00

README.md

This package defines primitives for sentry access to application memory.

Major types:

  • The IO interface represents a virtual address space and provides I/O methods on that address space. IO is the lowest-level primitive. The primary implementation of the IO interface is mm.MemoryManager.

  • IOSequence represents a collection of individually-contiguous address ranges in a IO that is operated on sequentially, analogous to Linux's struct 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 kernel package (e.g. most syscall implementations in syscalls/linux); use the kernel.Task.Copy* wrappers defined in kernel/task_usermem.go.

  • Access to a task's virtual memory, from a context that is at or above the level of the kernel package, but where any of the above constraints does not hold (e.g. PTRACE_POKEDATA, which ignores application memory protections); obtain the task's mm.MemoryManager by calling kernel.Task.MemoryManager, and call its IO methods directly.

  • Access to a task's virtual memory, from a context that is below the level of the kernel package (e.g. filesystem I/O); clients must pass I/O arguments from higher layers, usually in the form of an IOSequence. The kernel.Task.SingleIOSequence and kernel.Task.IovecsIOSequence functions in kernel/task_usermem.go are convenience functions for doing so.