Commit Graph

87 Commits

Author SHA1 Message Date
Sam Balana 82a5cada59 Add AfterFunc to tcpip.Clock
Changes the API of tcpip.Clock to also provide a method for scheduling and
rescheduling work after a specified duration. This change also implements the
AfterFunc method for existing implementations of tcpip.Clock.

This is the groundwork required to mock time within tests. All references to
CancellableTimer has been replaced with the tcpip.Job interface, allowing for
custom implementations of scheduling work.

This is a BREAKING CHANGE for clients that implement their own tcpip.Clock or
use tcpip.CancellableTimer. Migration plan:
 1. Add AfterFunc(d, f) to tcpip.Clock
 2. Replace references of tcpip.CancellableTimer with tcpip.Job
 3. Replace calls to tcpip.CancellableTimer#StopLocked with tcpip.Job#Cancel
 4. Replace calls to tcpip.CancellableTimer#Reset with tcpip.Job#Schedule
 5. Replace calls to tcpip.NewCancellableTimer with tcpip.NewJob.

PiperOrigin-RevId: 322906897
2020-07-23 18:00:43 -07:00
Ridwan Sharif abffebde7b Gate FUSE behind a runsc flag
This change gates all FUSE commands (by gating /dev/fuse) behind a runsc
flag. In order to use FUSE commands, use the --fuse flag with the --vfs2
flag. Check if FUSE is enabled by running dmesg in the sandbox.
2020-07-09 02:01:29 -04:00
Adin Scannell 364ac92baf Support for saving pointers to fields in the state package.
Previously, it was not possible to encode/decode an object graph which
contained a pointer to a field within another type. This was because the
encoder was previously unable to disambiguate a pointer to an object and a
pointer within the object.

This CL remedies this by constructing an address map tracking the full memory
range object occupy. The encoded Refvalue message has been extended to allow
references to children objects within another object. Because the encoding
process may learn about object structure over time, we cannot encode any
objects under the entire graph has been generated.

This CL also updates the state package to use standard interfaces intead of
reflection-based dispatch in order to improve performance overall. This
includes a custom wire protocol to significantly reduce the number of
allocations and take advantage of structure packing.

As part of these changes, there are a small number of minor changes in other
places of the code base:

* The lists used during encoding are changed to use intrusive lists with the
  objectEncodeState directly, which required that the ilist Len() method is
  updated to work properly with the ElementMapper mechanism.

* A bug is fixed in the list code wherein Remove() called on an element that is
  already removed can corrupt the list (removing the element if there's only a
  single element). Now the behavior is correct.

* Standard error wrapping is introduced.

* Compressio was updated to implement the new wire.Reader and wire.Writer
  inteface methods directly. The lack of a ReadByte and WriteByte caused issues
  not due to interface dispatch, but because underlying slices for a Read or
  Write call through an interface would always escape to the heap!

* Statify has been updated to support the new APIs.

See README.md for a description of how the new mechanism works.

PiperOrigin-RevId: 318010298
2020-06-23 23:34:06 -07:00
Nicolas Lacasse 810748f5c9 Port aio to VFS2.
In order to make sure all aio goroutines have stopped during S/R, a new
WaitGroup was added to TaskSet, analagous to runningGoroutines. This WaitGroup
is incremented with each aio goroutine, and waited on during kernel.Pause.

The old VFS1 aio code was changed to use this new WaitGroup, rather than
fs.Async. The only uses of fs.Async are now inode and mount Release operations,
which do not call fs.Async recursively. This fixes a lock-ordering violation
that can cause deadlocks.

Updates #1035.

PiperOrigin-RevId: 316689380
2020-06-16 08:49:06 -07:00
Jamie Liu 3b0b1f104d Miscellaneous VFS2 fixes.
PiperOrigin-RevId: 316627764
2020-06-16 00:15:20 -07:00
Fabricio Voznika 67565078bb Implement flock(2) in VFS2
LockFD is the generic implementation that can be embedded in
FileDescriptionImpl implementations. Unique lock ID is
maintained in vfs.FileDescription and is created on demand.

Updates #1480

PiperOrigin-RevId: 315604825
2020-06-09 18:46:42 -07:00
Nicolas Lacasse 47dfba7661 Port memfd_create to vfs2 and finish implementation of file seals.
Closes #2612.

PiperOrigin-RevId: 311548074
2020-05-14 09:35:54 -07:00
Jamie Liu 9115f26851 Allocate device numbers for VFS2 filesystems.
Updates #1197, #1198, #1672

PiperOrigin-RevId: 310432006
2020-05-07 14:01:53 -07:00
Nicolas Lacasse d0b1d0233d Move pkg/sentry/vfs/{eventfd,timerfd} to new packages in pkg/sentry/fsimpl.
They don't depend on anything in VFS2, so they should be their own packages.

PiperOrigin-RevId: 310416807
2020-05-07 12:44:03 -07:00
Dean Deng 1b88c63b3e Move hostfs mount to Kernel struct.
This is needed to set up host fds passed through a Unix socket. Note that
the host package depends on kernel, so we cannot set up the hostfs mount
directly in Kernel.Init as we do for sockfs and pipefs.

Also, adjust sockfs to make its setup look more like hostfs's and pipefs's.

PiperOrigin-RevId: 308274053
2020-04-24 10:03:43 -07:00
Jamie Liu f03996c5e9 Implement pipe(2) and pipe2(2) for VFS2.
Updates #1035

PiperOrigin-RevId: 306968644
2020-04-16 19:27:03 -07:00
Nicolas Lacasse f332a864e8 Port timerfd to VFS2.
PiperOrigin-RevId: 305067208
2020-04-06 10:52:56 -07:00
Dean Deng 24bee1c181 Record VFS2 sockets in global socket map.
Updates #1476, #1478, #1484, #1485.

PiperOrigin-RevId: 304845354
2020-04-04 21:02:42 -07:00
Bhasker Hariharan fc99a7ebf0 Refactor software GSO code.
Software GSO implementation currently has a complicated code path with
implicit assumptions that all packets to WritePackets carry same Data
and it does this to avoid allocations on the path etc. But this makes it
hard to reuse the WritePackets API.

This change breaks all such assumptions by introducing a new Vectorised
View API ReadToVV which can be used to cleanly split a VV into multiple
independent VVs. Further this change also makes packet buffers linkable
to form an intrusive list. This allows us to get rid of the array of
packet buffers that are passed in the WritePackets API call and replace
it with a list of packet buffers.

While this code does introduce some more allocations in the benchmarks
it doesn't cause any degradation.

Updates #231

PiperOrigin-RevId: 304731742
2020-04-03 18:35:55 -07:00
Dean Deng 639d94f9f7 Add socket filesystem and global disconnected socket mount for VFS2.
A socket mount where anonymous sockets will reside is added to the
VirtualFilesystem. Socketfs is built on top of kernfs.

Updates #1476, #1478, #1484, #1485.

PiperOrigin-RevId: 304095251
2020-03-31 19:17:12 -07:00
Dean Deng 5e413cad10 Plumb VFS2 imported fds into virtual filesystem.
- When setting up the virtual filesystem, mount a host.filesystem to contain
  all files that need to be imported.
- Make read/preadv syscalls to the host in cases where preadv2 may not be
  supported yet (likewise for writing).
- Make save/restore functions in kernel/kernel.go return early if vfs2 is
  enabled.

PiperOrigin-RevId: 300922353
2020-03-14 07:14:33 -07:00
Ting-Yu Wang 6b4d36e325 Hide /dev/net/tun when using hostinet.
/dev/net/tun does not currently work with hostinet. This has caused some
program starts failing because it thinks the feature exists.

PiperOrigin-RevId: 297876196
2020-02-28 10:39:12 -08:00
Fabricio Voznika 72e3f3a3ee Add option to skip stuck tasks waiting for address space
PiperOrigin-RevId: 297192390
2020-02-25 13:44:18 -08:00
gVisor bot 4a73bae269 Initial network namespace support.
TCP/IP will work with netstack networking. hostinet doesn't work, and sockets
will have the same behavior as it is now.

Before the userspace is able to create device, the default loopback device can
be used to test.

/proc/net and /sys/net will still be connected to the root network stack; this
is the same behavior now.

Issue #1833

PiperOrigin-RevId: 296309389
2020-02-20 15:20:40 -08:00
gVisor bot 5baf9dc2fb Synchronize signalling with S/R
This is to fix a data race between sending an external signal to
a ThreadGroup and kernel saving state for S/R.

PiperOrigin-RevId: 295244281
2020-02-14 15:49:09 -08:00
gVisor bot e4c7f3e6f6 Inline vfs.VirtualFilesystem in Kernel struct
This saves one pointer dereference per VFS access.

Updates #1623

PiperOrigin-RevId: 295216176
2020-02-14 13:40:39 -08:00
gVisor bot 4075de11be Plumb VFS2 inside the Sentry
- Added fsbridge package with interface that can be used to open
  and read from VFS1 and VFS2 files.
- Converted ELF loader to use fsbridge
- Added VFS2 types to FSContext
- Added vfs.MountNamespace to ThreadGroup

Updates #1623

PiperOrigin-RevId: 295183950
2020-02-14 11:12:47 -08:00
Adin Scannell 1b6a12a768 Add notes to relevant tests.
These were out-of-band notes that can help provide additional context
and simplify automated imports.

PiperOrigin-RevId: 293525915
2020-02-05 22:46:35 -08:00
Fabricio Voznika 437c986c6a Add vfs.FileDescription to FD table
FD table now holds both VFS1 and VFS2 types and uses the correct
one based on what's set.

Parts of this CL are just initial changes (e.g. sys_read.go,
runsc/main.go) to serve as a template for the remaining changes.

Updates #1487
Updates #1623

PiperOrigin-RevId: 292023223
2020-01-28 15:31:03 -08:00
Adin Scannell 0e2f1b7abd Update package locations.
Because the abi will depend on the core types for marshalling (usermem,
context, safemem, safecopy), these need to be flattened from the sentry
directory. These packages contain no sentry-specific details.

PiperOrigin-RevId: 291811289
2020-01-27 15:31:32 -08:00