Well that's an interesting one!
Apparently if you issue multiple concurrent preadv calls on
a TUN device using io_uring, the TUN device falls over.
Possibly corrupting memory along the way.
Which might be why the kernel hung on shutdown...
avoids a per-packet alloc
i will atone for my sins later
if only C let you return multiple values.
or Go let you pass in a pointer w/o it being on the heap.
This does a few things:
1. Rewrites the tests so that we get a log of what individual tests
failed at the end of a test run.
2. Adds a test that runs an HTTP server via the tester tailscale node and
then has the VMs connect to that over Tailscale.
3. Dials the VM over Tailscale and ensures it answers SSH requests.
4. Other minor framework refactoring.
Signed-off-by: Christine Dodrill <xe@tailscale.com>
Oracle Linux[1] is a CentOS fork. It is not very special. I am adding it
to the integration jungle because I am adding it to pkgs and the website
directions.
[1]: https://www.oracle.com/linux/
Signed-off-by: Christine Dodrill <xe@tailscale.com>
To remove some multi-case selects, we intentionally allowed
sends on closed channels (cc23049cd2).
However, we also introduced concurrent sends and closes,
which is a data race.
This commit fixes the data race. The mutexes here are uncontended,
and thus very cheap.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
It was caching too aggressively, as it didn't see our deps due to our
running "go install tailscaled" as a child process.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
version.sh was removed in commit 5088af68. Use `build_dist.sh shellvars`
to provide version information instead.
Signed-off-by: Irshad Pananilath <pmirshad+code@gmail.com>
This makes sure `tailscale status` and `tailscale ping` works. It also
switches goexpect to use a batch instead of manually banging out each
line, which makes the tests so much easier to read.
Signed-off-by: Christine Dodrill <xe@tailscale.com>
Running hex.Encode(b, b) is a bad idea.
The first byte of input will overwrite the first two bytes of output.
Subsequent bytes have no impact on the output.
Not related to today's IPv6 bug, but...wh::ps.
This caused us to spuriously ignore some wireguard config updates.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Calculate whether the packet is injected directly,
rather than via an else branch.
Unify the exit paths. It is easier here than duplicating them.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Every TUN Read went through several multi-case selects.
We know from past experience with wireguard-go that these are slow
and cause scheduler churn.
The selects served two purposes: they separated errors from data and
gracefully handled shutdown. The first is fairly easy to replace by sending
errors and data over a single channel. The second, less so.
We considered a few approaches: Intricate webs of channels,
global condition variables. They all get ugly fast.
Instead, let's embrace the ugly and handle shutdown ungracefully.
It's horrible, but the horror is simple and localized.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
The implementation of the preview function has changed since the
API was documented, update the document to match.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
We can't access b.netMap without holding b.mu.
We already grabbed it earlier in the function with the lock held.
Introduced in Nov 2020 in 7ea809897d.
Discovered during stress testing.
Apparently it's a pretty rare?
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
