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
If a background process tries to read from a TTY, linux sends it a SIGTTIN
unless the signal is blocked or ignored, or the process group is an orphan, in
which case the syscall returns EIO.
See drivers/tty/n_tty.c:n_tty_read()=>job_control().
If a background process tries to write a TTY, set the termios, or set the
foreground process group, linux then sends a SIGTTOU. If the signal is ignored
or blocked, linux allows the write. If the process group is an orphan, the
syscall returns EIO.
See drivers/tty/tty_io.c:tty_check_change().
PiperOrigin-RevId: 234044367
Change-Id: I009461352ac4f3f11c5d42c43ac36bb0caa580f9
Updated error messages so that it doesn't print full Go struct representations
when running a new container in a sandbox. For example, this occurs frequently
when commands are not found when doing a 'kubectl exec'.
PiperOrigin-RevId: 219729141
Change-Id: Ic3a7bc84cd7b2167f495d48a1da241d621d3ca09
Terminal support in runsc relies on host tty file descriptors that are imported
into the sandbox. Application tty ioctls are sent directly to the host fd.
However, those host tty ioctls are associated in the host kernel with a host
process (in this case runsc), and the host kernel intercepts job control
characters like ^C and send signals to the host process. Thus, typing ^C into a
"runsc exec" shell will send a SIGINT to the runsc process.
This change makes "runsc exec" handle all signals, and forward them into the
sandbox via the "ContainerSignal" urpc method. Since the "runsc exec" is
associated with a particular container process in the sandbox, the signal must
be associated with the same container process.
One big difficulty is that the signal should not necessarily be sent to the
sandbox process started by "exec", but instead must be sent to the foreground
process group for the tty. For example, we may exec "bash", and from bash call
"sleep 100". A ^C at this point should SIGINT sleep, not bash.
To handle this, tty files inside the sandbox must keep track of their
foreground process group, which is set/get via ioctls. When an incoming
ContainerSignal urpc comes in, we look up the foreground process group via the
tty file. Unfortunately, this means we have to expose and cache the tty file in
the Loader.
Note that "runsc exec" now handles signals properly, but "runs run" does not.
That will come in a later CL, as this one is complex enough already.
Example:
root@:/usr/local/apache2# sleep 100
^C
root@:/usr/local/apache2# sleep 100
^Z
[1]+ Stopped sleep 100
root@:/usr/local/apache2# fg
sleep 100
^C
root@:/usr/local/apache2#
PiperOrigin-RevId: 215334554
Change-Id: I53cdce39653027908510a5ba8d08c49f9cf24f39
There was a race where we checked task.Parent() != nil, and then later called
task.Parent() again, assuming that it is not nil. If the task is exiting, the
parent may have been set to nil in between the two calls, causing a panic.
This CL changes the code to only call task.Parent() once.
PiperOrigin-RevId: 215274456
Change-Id: Ib5a537312c917773265ec72016014f7bc59a5f59
In order to implement kill --all correctly, the Sentry needs
to track all tasks that belong to a given container. This change
introduces ContainerID to the task, that gets inherited by all
children. 'kill --all' then iterates over all tasks comparing the
ContainerID field to find all processes that need to be signalled.
PiperOrigin-RevId: 214841768
Change-Id: I693b2374be8692d88cc441ef13a0ae34abf73ac6
Old code was returning ID of the thread that created
the child process. It should be returning the ID of
the parent process instead.
PiperOrigin-RevId: 214720910
Change-Id: I95715c535bcf468ecf1ae771cccd04a4cd345b36
This makes `runsc wait` behave more like waitpid()/wait4() in that:
- Once a process has run to completion, you can wait on it and get its exit
code.
- Processes not waited on will consume memory (like a zombie process)
PiperOrigin-RevId: 213358916
Change-Id: I5b5eca41ce71eea68e447380df8c38361a4d1558
The contract in ExecArgs says that a reference on ExecArgs.Root must be held
for the lifetime of the struct, but the caller is free to drop the ref after
that.
As a result, proc.Exec must take an additional ref on Root when it constructs
the CreateProcessArgs, since that holds a pointer to Root as well. That ref is
dropped in CreateProcess.
PiperOrigin-RevId: 212828348
Change-Id: I7f44a612f337ff51a02b873b8a845d3119408707
This is different from the existing -pid-file flag, which saves a host pid.
PiperOrigin-RevId: 212713968
Change-Id: I2c486de8dd5cfd9b923fb0970165ef7c5fc597f0
We must use a context.Context with a Root Dirent that corresponds to the
container's chroot. Previously we were using the root context, which does not
have a chroot.
Getting the correct context required refactoring some of the path-lookup code.
We can't lookup the path without a context.Context, which requires
kernel.CreateProcArgs, which we only get inside control.Execute. So we have to
do the path lookup much later than we previously were.
PiperOrigin-RevId: 212064734
Change-Id: I84a5cfadacb21fd9c3ab9c393f7e308a40b9b537
This CL adds terminal support for "docker exec". We previously only supported
consoles for the container process, but not exec processes.
The SYS_IOCTL syscall was added to the default seccomp filter list, but only
for ioctls that get/set winsize and termios structs. We need to allow these
ioctl for all containers because it's possible to run "exec -ti" on a
container that was started without an attached console, after the filters
have been installed.
Note that control-character signals are still not properly supported.
Tested with:
$ docker run --runtime=runsc -it alpine
In another terminial:
$ docker exec -it <containerid> /bin/sh
PiperOrigin-RevId: 210185456
Change-Id: I6d2401e53a7697bb988c120a8961505c335f96d9
Resume checks the status of the container and unpauses the kernel
if its status is paused. Otherwise nothing happens.
Tests were added to ensure that the process is in the correct state
after various commands.
PiperOrigin-RevId: 201251234
Change-Id: Ifd11b336c33b654fea6238738f864fcf2bf81e19
Detachable exec commands are handled in the client entirely and the detach option is not used anymore.
PiperOrigin-RevId: 195181272
Change-Id: I6e82a2876d2c173709c099be59670f71702e5bf0
Adin Scannell
Michael Pratt
Nicolas Lacasse
Ian Lewis
Ian Gudger
Fabricio Voznika
Kevin Krakauer
Justine Olshan
Googler