Before destroying the Kernel, we disable signal forwarding,
relinquishing control to the Go runtime. External signals that arrive
after disabling forwarding but before the sandbox exits thus may use
runtime.raise (i.e., tkill(2)) and violate the syscall filters.
Adjust forwardSignals to handle signals received after disabling
forwarding the same way they are handled before starting forwarding.
i.e., by implementing the standard Go runtime behavior using tgkill(2)
instead of tkill(2).
This also makes the stop callback block until forwarding actually stops.
This isn't required to avoid tkill(2) but is a saner interface.
PiperOrigin-RevId: 211995946
Change-Id: I3585841644409260eec23435cf65681ad41f5f03
It was always returning the MountNamespace root, which may be different from
the process Root if the process is in a chroot environment.
PiperOrigin-RevId: 211862181
Change-Id: I63bfeb610e2b0affa9fdbdd8147eba3c39014480
Now that it's possible to remove subnets, we must iterate over them with locks
held.
Also do the removal more efficiently while I'm here.
PiperOrigin-RevId: 211737416
Change-Id: I29025ec8b0c3ad11f22d4447e8ad473f1c785463
Makes it possible to avoid copying or allocating in cases where DeliverNetworkPacket (rx)
needs to turn around and call WritePacket (tx) with its VectorisedView.
Also removes the restriction on having VectorisedViews with multiple views in the write path.
PiperOrigin-RevId: 211728717
Change-Id: Ie03a65ecb4e28bd15ebdb9c69f05eced18fdfcff
Furthermore, allow for the specification of an ElementMapper. This allows a
single "Element" type to exist on multiple inline lists, and work without
having to embed the entry type.
This is a requisite change for supporting a per-Inode list of Dirents.
PiperOrigin-RevId: 211467497
Change-Id: If2768999b43e03fdaecf8ed15f435fe37518d163
Task.creds can only be changed by the task's own set*id and execve
syscalls, and Task namespaces can only be changed by the task's own
unshare/setns syscalls.
PiperOrigin-RevId: 211156279
Change-Id: I94d57105d34e8739d964400995a8a5d76306b2a0
From //pkg/sentry/context/context.go:
// - It is *not safe* to retain a Context passed to a function beyond the scope
// of that function call.
Passing a stored kernel.Task as a context.Context to
fs.FileOwnerFromContext violates this requirement.
PiperOrigin-RevId: 211143021
Change-Id: I4c5b02bd941407be4c9cfdbcbdfe5a26acaec037
This allows us to call kernel.FDMap.DecRef without holding mutexes
cleanly.
PiperOrigin-RevId: 211139657
Change-Id: Ie59d5210fb9282e1950e2e40323df7264a01bcec
This CL does NDP link-address discovery for IPv6.
It includes several small changes necessary to get linux to talk to
this implementation. In particular, a hop limit of 255 is necessary
for ICMPv6.
PiperOrigin-RevId: 211103930
Change-Id: If25370ab84c6b1decfb15de917f3b0020f2c4e0e
dirent.walk() takes renameMu, but is often called with renameMu already held,
which can lead to a deadlock.
Fix this by requiring renameMu to be held for reading when dirent.walk() is
called. This causes walks and existence checks to block while a rename
operation takes place, but that is what we were already trying to enforce by
taking renameMu in walk() anyways.
PiperOrigin-RevId: 210760780
Change-Id: Id61018e6e4adbeac53b9c1b3aa24ab77f75d8a54
dirent.go:Rename() walks to the file being replaced and defers
replaced.DecRef(). After the rename, the reference is dropped, triggering a
writeout and SettAttr call to the gofer. Because of lazyOpenForWrite, the gofer
opens the replaced file BY ITS OLD NAME and calls ftruncate on it.
This CL changes Remove to drop the reference on replaced (and thus trigger
writeout) before the actual rename call.
PiperOrigin-RevId: 210756097
Change-Id: I01ea09a5ee6c2e2d464560362f09943641638e0f
Weak references save / restore involves multiple interface indirection
and cause material latency overhead when there are lots of dirents, each
containing a weak reference map. The nil entries in the map should also
be purged.
PiperOrigin-RevId: 210593727
Change-Id: Ied6f4c3c0726fcc53a24b983d9b3a79121b6b758
This is to troubleshoot problems with a hung process that is
not responding to 'runsc debug --stack' command.
PiperOrigin-RevId: 210483513
Change-Id: I4377b210b4e51bc8a281ad34fd94f3df13d9187d
When revalidating a Dirent, if the inode id is the same, then we don't need to
throw away the entire Dirent. We can just update the unstable attributes in
place.
If the inode id has changed, then the remote file has been deleted or moved,
and we have no choice but to throw away the dirent we have a look up another.
In this case, we may still end up losing a mounted dirent that is a child of
the revalidated dirent. However, that seems appropriate here because the entire
mount point has been pulled out from underneath us.
Because gVisor's overlay is at the Inode level rather than the Dirent level, we
must pass the parent Inode and name along with the Inode that is being
revalidated.
PiperOrigin-RevId: 210431270
Change-Id: I705caef9c68900234972d5aac4ae3a78c61c7d42
Implements the TIOCGWINSZ and TIOCSWINSZ ioctls, which allow processes to resize
the terminal. This allows, for example, sshd to properly set the window size for
ssh sessions.
PiperOrigin-RevId: 210392504
Change-Id: I0d4789154d6d22f02509b31d71392e13ee4a50ba
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
Compared to previous compressio / hashio nesting, there is up to 100% speedup.
PiperOrigin-RevId: 210161269
Change-Id: I481aa9fe980bb817fe465fe34d32ea33fc8abf1c
As required by the contract in Dirent.flush().
Also inline Dirent.freeze() into Dirent.Freeze(), since it is only called from
there.
PiperOrigin-RevId: 209783626
Change-Id: Ie6de4533d93dd299ffa01dabfa257c9cc259b1f4
Fabricio Voznika
Michael Pratt
Nicolas Lacasse
Tamir Duberstein
Bert Muthalaly
Brian Geffon
Bhasker Hariharan
Adin Scannell
Googler
Jamie Liu
Ian Gudger
Zhaozhong Ni
Kevin Krakauer
Tamir Duberstein