passt, branch 2022_10_26.e4df8b0

test/run: Temporarily disable distribution tests

2022-10-26T05:03:56+00:00

They're too slow to cope with current release cycles, and they
haven't found bugs in months, also because clang-tidy and cppcheck
would find most of them earlier.

Disable them for the moment. We should pre-install gcc and make in
non-x86 images, as those run on my test machine with qemu TCG, and
that's the real slow-down here. Then we can re-enable them.

Signed-off-by: Stefano Brivio

hooks: Temporarily disable demo generation in pre-push

2022-10-26T04:56:25+00:00

The out-of-tree Podman patch needs to be rebased every second week or
so, and I'm currently trying to get that upstream:
  https://github.com/containers/podman/pull/16141

Disable demo generation for the moment, so that I avoid wasting time
with those rebases. We'll re-enable it later.

Signed-off-by: Stefano Brivio

test: Add log file tests for pasta plus corresponding layout and setup

2022-10-26T04:28:41+00:00

To test log files on a tmpfs mount, we need to unshare the mount
namespace, which means using a context for the passt pane is not
really practical at the moment, as we can't open a shell there, so
we would have to encapsulate all the commands under 'unshare -rUm',
plus the "inner" pasta command, running in turn a tcp_rr server.

It might be worth fixing this by e.g. detecting we are trying to
spawn an interactive shell and adding a special path in the context
setup with some form of stdin redirection -- I'm not sure it's doable
though.

For this reason, add a new layout, using a context only for the host
pane, while keeping the old command dispatch mechanism for the passt
pane.

We also need a new setup function that doesn't start pasta: we want
to start and restart it with different options.

Further, we need a 'pint' directive, to send an interrupt to the
passt pane: add that in lib/test.

All the tests before the one involving tmpfs and a detached mount
namespace were also tested with the context mechanism. To make an
eventual conversion easier, pass tcp_crr directly as a command on
pasta's command line where feasible.

While at it, fix the comment to the teardown_pasta() function.

The new test set can be semi-conveniently run as:

  ./run pasta_options/log_to_file

and it checks basic log creation, size of the log file after flooding
it with debug entries, rotations, and basic consistency after
rotations, on both an existing filesystem and a tmpfs, chosen as
it doesn't support collapsing data ranges via fallocate(), hence
triggering the fall-back mechanism for logging rotation.

Signed-off-by: Stefano Brivio

checksum: Fix calculation for ICMP checksum on IPv4

2022-10-26T04:28:06+00:00

We need to zero out the checksum field before calculating the
checksum, of course. I have no idea how this passed the "icmp" test
set, looking into it.

Reported-by: Paul Holzinger 
Fixes: 67ab6171729c ("Add csum_icmp4() helper for calculating ICMP checksums")
Signed-off-by: Stefano Brivio 
Reviewed-by: David Gibson

conf: Don't pass leading ~ to parse_port_range() on exclusions

2022-10-24T12:37:22+00:00

Commit 84fec4e998b6 ("Clean up parsing of port ranges") drops the
strspn() call before the parsing of excluded port ranges, because now
we're checking against any stray characters at every step.

However, that also has the effect of passing ~ as first character to
the new parse_port_range(), which makes no sense: we already checked
that ~ is the first character before the call, so skip it.

Alona reported this output:
  Invalid port specifier ~15000,~15001,~15006,~15008,~15020,~15021,~15090

while the whole specifier is indeed valid.

Reported-by: Alona Paz 
Fixes: 84fec4e998b6 ("Clean up parsing of port ranges")
Signed-off-by: Stefano Brivio

util: Set NS_FN_STACK_SIZE to one eighth of ulimit-reported maximum stack size

2022-10-22T06:46:57+00:00

...instead of one fourth. On the main() -> conf() -> nl_sock_init()
call path, LTO from gcc 12 on (at least) x86_64 decides to inline...
everything: nl_sock_init() is effectively part of main(), after
commit 3e2eb4337bc0 ("conf: Bind inbound ports with
CAP_NET_BIND_SERVICE before isolate_user()").

This means we exceed the maximum stack size, and we get SIGSEGV,
under any condition, at start time, as reported by Andrea on a recent
build for CentOS Stream 9.

The calculation of NS_FN_STACK_SIZE, which is the stack size we
reserve for clones, was previously obtained by dividing the maximum
stack size by two, to avoid an explicit check on architecture (on
PA-RISC, also known as hppa, the stack grows up, so we point the
clone to the middle of this area), and then further divided by two
to allow for any additional usage in the caller.

Well, if there are essentially no function calls anymore, this is
not enough. Divide it by eight, which is anyway much more than
possibly needed by any clone()d callee.

I think this is robust, so it's a fix in some sense. Strictly
speaking, though, we have no formal guarantees that this isn't
either too little or too much.

What we should do, eventually: check cloned() callees, there are just
thirteen of them at the moment. Note down any stack usage (they are
mostly small helpers), bonus points for an automated way at build
time, quadruple that or so, to allow for extreme clumsiness, and use
as NS_FN_STACK_SIZE. Perhaps introduce a specific condition for hppa.

Reported-by: Andrea Bolognani 
Fixes: 3e2eb4337bc0 ("conf: Bind inbound ports with CAP_NET_BIND_SERVICE before isolate_user()")
Signed-off-by: Stefano Brivio

Add git-publish configuration file

2022-10-22T01:45:50+00:00

Signed-off-by: Andrea Bolognani 
Reviewed-by: David Gibson 
Signed-off-by: Stefano Brivio

qrap: Support JSON syntax for -device

2022-10-21T09:43:45+00:00

Starting with version 8.1.0, libvirt uses JSON syntax when
generating the arguments to -device, so they will now look like

  {"driver":"virtio-scsi-pci","bus":"pci.3","addr":"0x0"}

instead of

  virtio-scsi-pci,bus=pci.3,addr=0x0

qrap needs to parse these arguments and extract the bus number
in order to figure out what address to use for the virtio-net
device it adds, and the libvirt change described above has
broken this parsing logic.

Tweak the code so that both styles are accepted and handled
correctly.

Note that, when JSON is in use, qrap needs to generate its own
command line options in that format as well or things will not
work as expected.

Signed-off-by: Andrea Bolognani 
Signed-off-by: Stefano Brivio

dhcp: Use tap_udp4_send() helper in dhcp()

2022-10-19T01:35:00+00:00

The IPv4 specific dhcp() manually constructs L2 and IP headers to send its
DHCP reply packet, unlike its IPv6 equivalent in dhcpv6.c which uses the
tap_udp6_send() helper.  Now that we've broaded the parameters to
tap_udp4_send() we can use it in dhcp() to avoid some duplicated logic.

Signed-off-by: David Gibson 
Signed-off-by: Stefano Brivio

tap: Split tap_ip4_send() into UDP and ICMP variants

2022-10-19T01:34:56+00:00

tap_ip4_send() has special case logic to compute the checksums for UDP
and ICMP packets, which is a mild layering violation.  By using a suitable
helper we can split it into tap_udp4_send() and tap_icmp4_send() functions
without greatly increasing the code size, this removing that layering
violation.

We make some small changes to the interface while there.  In both cases
we make the destination IPv4 address a parameter, which will be useful
later.  For the UDP variant we make it take just the UDP payload, and it
will generate the UDP header.  For the ICMP variant we pass in the ICMP
header as before.  The inconsistency is because that's what seems to be
the more natural way to invoke the function in the callers in each case.

Signed-off-by: David Gibson 
Signed-off-by: Stefano Brivio