Add a test to verify that skb metadata remains accessible after calling
bpf_skb_adjust_room(), which modifies the packet headroom and can trigger
head reallocation.
The helper expects an Ethernet frame carrying an IP packet so switch test
packet identification by source MAC address since we can no longer rely on
Ethernet proto being set to zero.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20251105-skb-meta-rx-path-v4-14-5ceb08a9b37b@cloudflare.com
Since pskb_expand_head() no longer clears metadata on unclone, update tests
for cloned packets to expect metadata to remain intact.
Also simplify the clone_dynptr_kept_on_{data,meta}_slice_write tests.
Creating an r/w dynptr slice is sufficient to trigger an unclone in the
prologue, so remove the extraneous writes to the data/meta slice.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20251105-skb-meta-rx-path-v4-12-5ceb08a9b37b@cloudflare.com
Move metadata verification into the BPF TC programs. Previously,
userspace read metadata from a map and verified it once at test end.
Now TC programs compare metadata directly using __builtin_memcmp() and
set a test_pass flag. This enables verification at multiple points during
test execution rather than a single final check.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20251105-skb-meta-rx-path-v4-10-5ceb08a9b37b@cloudflare.com
The existing XDP metadata test works by creating a veth pair and
attaching XDP & TC programs that drop the packet when the condition of
the test isn't fulfilled. The test then pings through the veth pair and
succeeds when the ping comes through.
While this test works great for a veth pair, it is hard to replicate for
tap devices to test the XDP metadata support of them. A similar test for
the tun driver would either involve logic to reply to the ping request,
or would have to capture the packet to check if it was dropped or not.
To make the testing of other drivers easier while still maximizing code
reuse, this commit refactors the existing xdp_context_functional test to
use a test_result map. Instead of conditionally passing or dropping the
packet, the TC program is changed to copy the received metadata into the
value of that single-entry array map. Tests can then verify that the map
value matches the expectation.
This testing logic is easy to adapt to other network drivers as the only
remaining requirement is that there is some way to send a custom
Ethernet packet through it that triggers the XDP & TC programs.
The Ethernet header of that custom packet is all-zero, because it is not
required to be valid for the test to work. The zero ethertype also helps
to filter out packets that are not related to the test and would
otherwise interfere with it.
The payload of the Ethernet packet is used as the test data that is
expected to be passed as metadata from the XDP to the TC program and
written to the map. It has a fixed size of 32 bytes which is a
reasonable size that should be supported by both drivers. Additional
packet headers are not necessary for the test and were therefore skipped
to keep the testing code short.
This new testing methodology no longer requires the veth interfaces to
have IP addresses assigned, therefore these were removed.
Signed-off-by: Marcus Wichelmann <marcus.wichelmann@hetzner-cloud.de>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250305213438.3863922-5-marcus.wichelmann@hetzner-cloud.de
Fix all selftests to include libbpf header files with the bpf/ prefix, to
be consistent with external users of the library. Also ensure that all
includes of exported libbpf header files (those that are exported on 'make
install' of the library) use bracketed includes instead of quoted.
To not break the build, keep the old include path until everything has been
changed to the new one; a subsequent patch will remove that.
Fixes: 6910d7d386 ("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157952560568.1683545.9649335788846513446.stgit@toke.dk
At the moment, all kernel bpf objects are listed under BPF_OBJ_FILES.
Listing them manually sometimes causing patch conflict when people are
adding new testcases simultaneously.
It is better to centre all the related source files under a subdir
"progs", then auto-generate the object file list.
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
