selftests/bpf: Fix merge conflict due to SYS() macro change.

Fix merge conflict between bpf/bpf-next trees due to change of arguments in SYS() macro.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: fix "metadata marker" getting overwritten by the netstack

Alexei noticed xdp_do_redirect test on BPF CI started failing on
BE systems after skb PP recycling was enabled:

test_xdp_do_redirect:PASS:prog_run 0 nsec
test_xdp_do_redirect:PASS:pkt_count_xdp 0 nsec
test_xdp_do_redirect:PASS:pkt_count_zero 0 nsec
test_xdp_do_redirect:FAIL:pkt_count_tc unexpected pkt_count_tc: actual
220 != expected 9998
test_max_pkt_size:PASS:prog_run_max_size 0 nsec
test_max_pkt_size:PASS:prog_run_too_big 0 nsec
close_netns:PASS:setns 0 nsec
#289 xdp_do_redirect:FAIL
Summary: 270/1674 PASSED, 30 SKIPPED, 1 FAILED

and it doesn't happen on LE systems.
Ilya then hunted it down to:

#0 0x0000000000aaeee6 in neigh_hh_output (hh=0x83258df0,
skb=0x88142200) at linux/include/net/neighbour.h:503
#1 0x0000000000ab2cda in neigh_output (skip_cache=false,
skb=0x88142200, n=<optimized out>) at linux/include/net/neighbour.h:544
#2 ip6_finish_output2 (net=net@entry=0x88edba00, sk=sk@entry=0x0,
skb=skb@entry=0x88142200) at linux/net/ipv6/ip6_output.c:134
#3 0x0000000000ab4cbc in __ip6_finish_output (skb=0x88142200, sk=0x0,
net=0x88edba00) at linux/net/ipv6/ip6_output.c:195
#4 ip6_finish_output (net=0x88edba00, sk=0x0, skb=0x88142200) at
linux/net/ipv6/ip6_output.c:206

xdp_do_redirect test places a u32 marker (0x42) right before the Ethernet
header to check it then in the XDP program and return %XDP_ABORTED if it's
not there. Neigh xmit code likes to round up hard header length to speed
up copying the header, so it overwrites two bytes in front of the Eth
header. On LE systems, 0x42 is one byte at `data - 4`, while on BE it's
`data - 1`, what explains why it happens only there.
It didn't happen previously due to that %XDP_PASS meant the page will be
discarded and replaced by a new one, but now it can be recycled as well,
while bpf_test_run code doesn't reinitialize the content of recycled
pages. This mark is limited to this particular test and its setup though,
so there's no need to predict 1000 different possible cases. Just move
it 4 bytes to the left, still keeping it 32 bit to match on more bytes.

Fixes: 9c94bbf9a87b ("xdp: recycle Page Pool backed skbs built from XDP frames")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/CAADnVQ+B_JOU+EpP=DKhbY9yXdN6GiRPnpTTXfEZ9sNkUeb-yQ@mail.gmail.com
Reported-by: Ilya Leoshkevich <iii@linux.ibm.com> # + debugging
Link: https://lore.kernel.org/bpf/8341c1d9f935f410438e79d3bd8a9cc50aefe105.camel@linux.ibm.com
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230316175051.922550-3-aleksander.lobakin@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: move SYS() macro into the test_progs.h

A lot of tests defined SYS() macro to run system calls with goto label.
Let's move this macro to test_progs.h and add configurable
"goto_label" as the first arg.

Suggested-by: Martin KaFai Lau <martin.lau@linux.dev>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://lore.kernel.org/r/20230224061343.506571-2-liuhangbin@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

selftests/bpf: fix xdp_redirect xdp-features selftest for veth driver

xdp-features supported by veth driver are no more static, but they
depends on veth configuration (e.g. if GRO is enabled/disabled or
TX/RX queue configuration). Take it into account in xdp_redirect
xdp-features selftest for veth driver.

Fixes: fccca038f300 ("veth: take into account device reconfiguration for xdp_features flag")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/bc35455cfbb1d4f7f52536955ded81ad47d8dc54.1680777371.git.lorenzo@kernel.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES

&xdp_buff and &xdp_frame are bound in a way that

xdp_buff->data_hard_start == xdp_frame

It's always the case and e.g. xdp_convert_buff_to_frame() relies on
this.
IOW, the following:

for (u32 i = 0; i < 0xdead; i++) {
xdpf = xdp_convert_buff_to_frame(&xdp);
xdp_convert_frame_to_buff(xdpf, &xdp);
}

shouldn't ever modify @xdpf's contents or the pointer itself.
However, "live packet" code wrongly treats &xdp_frame as part of its
context placed *before* the data_hard_start. With such flow,
data_hard_start is sizeof(*xdpf) off to the right and no longer points
to the XDP frame.

Instead of replacing `sizeof(ctx)` with `offsetof(ctx, xdpf)` in several
places and praying that there are no more miscalcs left somewhere in the
code, unionize ::frm with ::data in a flex array, so that both starts
pointing to the actual data_hard_start and the XDP frame actually starts
being a part of it, i.e. a part of the headroom, not the context.
A nice side effect is that the maximum frame size for this mode gets
increased by 40 bytes, as xdp_buff::frame_sz includes everything from
data_hard_start (-> includes xdpf already) to the end of XDP/skb shared
info.
Also update %MAX_PKT_SIZE accordingly in the selftests code. Leave it
hardcoded for 64 bit && 4k pages, it can be made more flexible later on.

Minor: align `&head->data` with how `head->frm` is assigned for
consistency.
Minor #2: rename 'frm' to 'frame' in &xdp_page_head while at it for
clarity.

(was found while testing XDP traffic generator on ice, which calls
xdp_convert_frame_to_buff() for each XDP frame)

Fixes: b530e9e1063e ("bpf: Add "live packet" mode for XDP in BPF_PROG_RUN")
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://lore.kernel.org/r/20230224163607.2994755-1-aleksander.lobakin@intel.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

Revert "bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES"

This reverts commit 6c20822fada1b8adb77fa450d03a0d449686a4a9.

build bot failed on arch with different cache line size:
https://lore.kernel.org/bpf/50c35055-afa9-d01e-9a05-ea5351280e4f@intel.com/

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES

&xdp_buff and &xdp_frame are bound in a way that

xdp_buff->data_hard_start == xdp_frame

It's always the case and e.g. xdp_convert_buff_to_frame() relies on
this.
IOW, the following:

for (u32 i = 0; i < 0xdead; i++) {
xdpf = xdp_convert_buff_to_frame(&xdp);
xdp_convert_frame_to_buff(xdpf, &xdp);
}

shouldn't ever modify @xdpf's contents or the pointer itself.
However, "live packet" code wrongly treats &xdp_frame as part of its
context placed *before* the data_hard_start. With such flow,
data_hard_start is sizeof(*xdpf) off to the right and no longer points
to the XDP frame.

Instead of replacing `sizeof(ctx)` with `offsetof(ctx, xdpf)` in several
places and praying that there are no more miscalcs left somewhere in the
code, unionize ::frm with ::data in a flex array, so that both starts
pointing to the actual data_hard_start and the XDP frame actually starts
being a part of it, i.e. a part of the headroom, not the context.
A nice side effect is that the maximum frame size for this mode gets
increased by 40 bytes, as xdp_buff::frame_sz includes everything from
data_hard_start (-> includes xdpf already) to the end of XDP/skb shared
info.
Also update %MAX_PKT_SIZE accordingly in the selftests code. Leave it
hardcoded for 64 bit && 4k pages, it can be made more flexible later on.

Minor: align `&head->data` with how `head->frm` is assigned for
consistency.
Minor #2: rename 'frm' to 'frame' in &xdp_page_head while at it for
clarity.

(was found while testing XDP traffic generator on ice, which calls
xdp_convert_frame_to_buff() for each XDP frame)

Fixes: b530e9e1063e ("bpf: Add "live packet" mode for XDP in BPF_PROG_RUN")
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://lore.kernel.org/r/20230215185440.4126672-1-aleksander.lobakin@intel.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

selftests/bpf: add test for bpf_xdp_query xdp-features support

Introduce a self-test to verify libbpf bpf_xdp_query capability to dump
the xdp-features supported by the device (lo and veth in this case).

Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/534550318a2c883e174811683909544c63632f05.1675245258.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Fix xdp_do_redirect on s390x

s390x cache line size is 256 bytes, so skb_shared_info must be aligned
on a much larger boundary than for x86. This makes the maximum packet
size smaller.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230128000650.1516334-11-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Remove serial from tests using {open,close}_netns

After removing the mount/umount dance from {open,close}_netns()
in the pervious patch, "serial_" can be removed from
the tests using {open,close}_netns().

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-7-martin.lau@linux.dev

selftests/bpf: Mount debugfs in setns_by_fd

Jiri reports broken test_progs after recent commit 68f8e3d4b916
("selftests/bpf: Make sure zero-len skbs aren't redirectable").
Apparently we don't remount debugfs when we switch back networking namespace.
Let's explicitly mount /sys/kernel/debug.

0: https://lore.kernel.org/bpf/63b85917-a2ea-8e35-620c-808560910819@meta.com/T/#ma66ca9c92e99eee0a25e40f422489b26ee0171c1

Fixes: a30338840fa5 ("selftests/bpf: Move open_netns() and close_netns() into network_helpers.c")
Reported-by: Jiri Olsa <olsajiri@gmail.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20221123200829.2226254-1-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: Add a test for maximum packet size in xdp_do_redirect

This adds an extra test to the xdp_do_redirect selftest for XDP live packet
mode, which verifies that the maximum permissible packet size is accepted
without any errors, and that a too big packet is correctly rejected.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220310225621.53374-2-toke@redhat.com

selftests/bpf: Add selftest for XDP_REDIRECT in BPF_PROG_RUN

This adds a selftest for the XDP_REDIRECT facility in BPF_PROG_RUN, that
redirects packets into a veth and counts them using an XDP program on the
other side of the veth pair and a TC program on the local side of the veth.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220309105346.100053-6-toke@redhat.com