We missed a function exit point. This was exacerbated by e3134bf
("device: defer state machine transitions until configuration is
complete"), but the bug existed prior. Minus provided the following
useful reproducer script:
#!/usr/bin/env bash
set -eux
make wireguard-go || exit 125
ip netns del test-ns || true
ip netns add test-ns
ip link add test-kernel type wireguard
wg set test-kernel listen-port 0 private-key <(echo "QMCfZcp1KU27kEkpcMCgASEjDnDZDYsfMLHPed7+538=") peer "eDPZJMdfnb8ZcA/VSUnLZvLB2k8HVH12ufCGa7Z7rHI=" allowed-ips 10.51.234.10/32
ip link set test-kernel netns test-ns up
ip -n test-ns addr add 10.51.234.1/24 dev test-kernel
port=$(ip netns exec test-ns wg show test-kernel listen-port)
ip link del test-go || true
./wireguard-go test-go
wg set test-go private-key <(echo "WBM7qimR3vFk1QtWNfH+F4ggy/hmO+5hfIHKxxI4nF4=") peer "+nj9Dkqpl4phsHo2dQliGm5aEiWJJgBtYKbh7XjeNjg=" allowed-ips 0.0.0.0/0 endpoint 127.0.0.1:$port
ip addr add 10.51.234.10/24 dev test-go
ip link set test-go up
ping -c2 -W1 10.51.234.1
Reported-by: minus <minus@mnus.de>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The deferred RUnlock calls weren't executing until all peers
had been processed. Add an anonymous function so that each
peer may be unlocked as soon as it is completed.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
There are more places where we'll need to add it later, when Go 1.18
comes out with support for it in the "net" package. Also, allowedips
still uses slices internally, which might be suboptimal.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
A peer.endpoint never becomes nil after being not-nil, so creation is
the only time we actually need to set this. This prevents a race from
when the variable is actually used elsewhere, and allows us to avoid an
expensive atomic.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Forgetting to seed the unsafe rng, the jitter before followed a fixed
pattern, which didn't help when a fleet of computers all boot at once.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Trying this for every peer winds up being very slow and precludes it
from acceptable runtime in the CI, so reduce this to 4.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Now that we have parent pointers hooked up, we can simply go right to
the node and remove it in place, rather than having to recursively walk
the entire trie.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This makes the insertion algorithm a bit more efficient, while also now
taking on the additional task of connecting up parent pointers. This
will be handy in the following commit.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Heavier network extensions might require the wireguard-go component to
use less ram, so let users of this reduce these as needed.
At some point we'll put this behind a configuration method of sorts, but
for now, just expose the consts as vars.
Requested-by: Josh Bleecher Snyder <josh@tailscale.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
On Linux we can run `ip link del wg0`, in which case the fd becomes
stale, and we should exit. Since this is an intentional action, don't
treat it as an error.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
When debugging, it's useful to know why a receive func exited.
We were already logging that, but only in the "death spiral" case.
Move the logging up, to capture it always.
Reduce the verbosity, since it is not an error case any more.
Put the receive func name in the log line.
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
Note: this bug is "hidden" by avoiding "death spiral" code path by
6228659 ("device: handle broader range of errors in RoutineReceiveIncoming").
If the code reached "death spiral" mechanism, there would be multiple
double frees happening. This results in a deadlock on iOS, because the
pools are fixed size and goroutine might stop until somebody makes
space in the pool.
This was almost 100% repro on the new ARM Macbooks:
- Build with 'ios' tag for Mac. This will enable bounded pools.
- Somehow call device.IpcSet at least couple of times (update config)
- device.BindUpdate() would be triggered
- RoutineReceiveIncoming would enter "death spiral".
- RoutineReceiveIncoming would stall on double free (pool is already
full)
- The stuck routine would deadlock 'device.closeBindLocked()' function
on line 'netc.stopping.Wait()'
Signed-off-by: Kristupas Antanavičius <kristupas.antanavicius@nordsec.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Instead of hard-coding exactly two sources from which
to receive packets (an IPv4 source and an IPv6 source),
allow the conn.Bind to specify a set of sources.
Beneficial consequences:
* If there's no IPv6 support on a system,
conn.Bind.Open can choose not to return a receive function for it,
which is simpler than tracking that state in the bind.
This simplification removes existing data races from both
conn.StdNetBind and bindtest.ChannelBind.
* If there are more than two sources on a system,
the conn.Bind no longer needs to add a separate muxing layer.
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
RoutineReceiveIncoming exits immediately on net.ErrClosed,
but not on other errors. However, for errors that are known
to be permanent, such as syscall.EAFNOSUPPORT,
we may as well exit immediately instead of retrying.
This considerably speeds up the package device tests right now,
because the Bind sometimes (incorrectly) returns syscall.EAFNOSUPPORT
instead of net.ErrClosed.
Signed-off-by: Josh Bleecher Snyder <josharian@gmail.com>
There's no way for len(peers)==0 when a current peer has
isRunning==false.
This requires some struct reshuffling so that the uint64 pointer is
aligned.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Googlers have a habit of graffiting their name in TODO items that then
are never addressed, and other people won't go near those because
they're marked territory of another animal. I've been gradually cleaning
these up as I see them, but this commit just goes all the way and
removes the remaining stragglers.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This code is stable, and the test is finicky, especially on high core
count systems, so just disable it.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
