Prior to this change tcpdump would fail to create its output file
because the destination directory was owned by root. This would later
cause killall to fail, as tcpdump was not running. Check exit code of
tcpdump/tshark to produce better error messages should this regress.
PiperOrigin-RevId: 346353911
Don't propagate arbitrary golang errors up from fusefs because errors
that don't map to an errno result in a sentry panic.
Reported-by: syzbot+697cb635346e456fddfc@syzkaller.appspotmail.com
PiperOrigin-RevId: 346220306
With the recent changes db36d948fa, we try
to balance the receive window advertisements between payload lengths vs
segment overhead length. This works fine when segment size are much
higher than the overhead, but not otherwise. In cases where the segment
length is smaller than the segment overhead, we may end up not
advertising zero receive window for long time and end up tail-dropping
segments. This is especially pronounced when application socket reads
are slow or stopped. In this change we do not grow the right edge of
the receive window for smaller segment sizes similar to Linux.
Also, we keep track of the socket buffer usage and let the window grow
if the application is actively reading data.
Fixes#4903
PiperOrigin-RevId: 345832012
The next test case is perfectly valid, which creates a test directory
with appropriate permissions and ensures that you can't create a file.
This test case assumes that the root directory has certain permissions.
In this case, we may have EROFS instead of a permission error, but it's
perfectly plausible that no error occurs at all. The test is not valid.
PiperOrigin-RevId: 345764412
These options allow overriding the signal that gets sent to the process when
I/O operations are available on the file descriptor, rather than the default
`SIGIO` signal. Doing so also populates `siginfo` to contain extra information
about which file descriptor caused the event (`si_fd`) and what events happened
on it (`si_band`). The logic around which FD is populated within `si_fd`
matches Linux's, which means it has some weird edge cases where that value may
not actually refer to a file descriptor that is still valid.
This CL also ports extra S/R logic regarding async handler in VFS2.
Without this, async I/O handlers aren't properly re-registered after S/R.
PiperOrigin-RevId: 345436598
It's possible that all the cases in a given batch are excluded if
the offsets line up just right, which will cause the test to fail.
Don't generate an invalid test in this case.
PiperOrigin-RevId: 345276588
Fixing the sendto deadlock exposed yet another deadlock where a lock inversion
occurs on the handleControlPacket path where e.mu and demuxer.epsByNIC.mu are
acquired in reverse order from say when RegisterTransportEndpoint is called
in endpoint.Connect().
This fix sidesteps the issue by just making endpoint.state an atomic and gets rid
of the need to acquire e.mu in e.HandleControlPacket.
PiperOrigin-RevId: 344939895
...as defined by RFC 2710. Querier (router)-side MLDv1 is not yet
supported.
The core state machine is shared with IGMPv2.
This is guarded behind a flag (ipv6.Options.MLDEnabled).
Tests: ip_test.TestMGP*
Bug #4861
PiperOrigin-RevId: 344344095
To create DUTs in parallel, we need to create goroutines to do the setup. The
old code base has a lot of t.Fatal(f) usage in those setup functions which is
not great for this change: "FailNow must be called from the goroutine running
the test or benchmark function, not from other goroutines created during the
test" (https://golang.org/pkg/testing/#T.FailNow).
- Cleanup all t.Fatal(f) usage in DUT.Prepare()
- use goroutines to create DUTs in parallel
PiperOrigin-RevId: 344275809
Because the code handles a bad header as "payload" right up to the last moment
we need to make sure payload handling does not remove the error information.
Fixes#4909
PiperOrigin-RevId: 344141690
1. setsockopt(SO_RCVTIMEO, 0) == never timeout
2. float64(time.Microsecond/time.Second) == 0
3. packetimpact tests use a lot of 1s timeouts
This becomes a more significant problem because of a recent change that binds
the sniffer only on the specific testNet interface so now the traffic on the
ctrlNet cannot wake up the blocking call anymore.
PiperOrigin-RevId: 344123465
Summary of the approach: the test runner will set up a few DUTs according to
a flag and pass all the test networks to the testbench. The testbench will only
reside in a single container. The testbench will put all the test networks into
a buffered channel which served as a semaphore and now the user can freely use
t.Parallel() in (sub)tests and the true parallelism will be determined by how
many DUTs are configured. Creating DUTs on demand is not supported yet, the
test author should determine the number of DUTs to be used statically.
Specifically in this change:
- Don't export any global variables about the test network in testbench.
- Sniffer only binds on the local interface because it will be possible to have
multiple interfaces to multiple DUTs in a single testbench container.
- Migrate existing tests to stop using global variables.
PiperOrigin-RevId: 343965962
Not all files are always accessible by the process itself. This
was specifically seen with map_files, but there's no rule that
every entry must be accessible by the process itself.
PiperOrigin-RevId: 343919117
Group addressable endpoints can simply check if it has joined the
multicast group without maintaining address endpoints. This also
helps remove the dependency on AddressableEndpoint from
GroupAddressableEndpoint.
Now that group addresses are not tracked with address endpoints, we can
avoid accidentally obtaining a route with a multicast local address.
PiperOrigin-RevId: 343336912
This changes also introduces:
- `SocketOptionsHandler` interface which can be implemented by endpoints to
handle endpoint specific behavior on SetSockOpt. This is analogous to what
Linux does.
- `DefaultSocketOptionsHandler` which is a default implementation of the above.
This is embedded in all endpoints so that we don't have to uselessly
implement empty functions. Endpoints with specific behavior can override the
embedded method by manually defining its own implementation.
PiperOrigin-RevId: 343158301
This change also makes the following fixes:
- Make SocketOptions use atomic operations instead of having to acquire/drop
locks upon each get/set option.
- Make documentation more consistent.
- Remove tcpip.SocketOptions from socketOpsCommon because it already exists
in transport.Endpoint.
- Refactors get/set socket options tests to be easily extendable.
PiperOrigin-RevId: 343103780
In UDP endpoint.Write() sendUDP is called with e.mu Rlocked. But if this happens
to send a datagram over loopback which ends up generating an ICMP response of
say ErrNoPortReachable, the handling of the response in HandleControlPacket also
acquires e.mu using RLock. This is mostly fine unless there is a competing
caller trying to acquire e.mu in exclusive mode using Lock(). This will deadlock
as a caller waiting in Lock() disallows an new RLocks() to ensure it can
actually acquire the Lock.
This is documented here https://golang.org/pkg/sync/#RWMutex.
This change releases the endpoint mutex before calling sendUDP to resolve the
possibility of the deadlock.
Reported-by: syzbot+537989797548c66e8ee3@syzkaller.appspotmail.com
Reported-by: syzbot+eb0b73b4ab486f7673ba@syzkaller.appspotmail.com
PiperOrigin-RevId: 342894148
Fixes the behaviour of SO_ERROR for tcp sockets where in linux it returns
sk->sk_err and if sk->sk_err is 0 then it returns sk->sk_soft_err. In gVisor TCP
we endpoint.HardError is the equivalent of sk->sk_err and endpoint.LastError
holds soft errors. This change brings this into alignment with Linux such that
both hard/soft errors are cleared when retrieved using getsockopt(.. SO_ERROR)
is called on a socket.
Fixes#3812
PiperOrigin-RevId: 342868552
As part of this, change Task.interrupted() to not drain Task.interruptChan, and
do so explicitly using new function Task.unsetInterrupted() instead.
PiperOrigin-RevId: 342768365
- Make AddressableEndpoint optional for NetworkEndpoint.
Not all NetworkEndpoints need to support addressing (e.g. ARP), so
AddressableEndpoint should only be implemented for protocols that
support addressing such as IPv4 and IPv6.
With this change, tcpip.ErrNotSupported will be returned by the stack
when attempting to modify addresses on a network endpoint that does
not support addressing.
Now that packets are fully handled at the network layer, and (with this
change) addresses are optional for network endpoints, we no longer need
the workaround for ARP where a fake ARP address was added to each NIC
that performs ARP so that packets would be delivered to the ARP layer.
PiperOrigin-RevId: 342722547
Zeling Feng
Tamir Duberstein
Rahat Mahmood
Zach Koopmans
Peter Johnston
gVisor bot
Mithun Iyer
Adin Scannell
Bruno Dal Bo
Jing Chen
Etienne Perot
Arthur Sfez
Bhasker Hariharan
Jamie Liu
Ghanan Gowripalan
Robin Luk
Julian Elischer
Fabricio Voznika
Ayush Ranjan
Toshi Kikuchi