With latest net-next:
====
clang -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/6.3.1/include -I./arch/x86/include -I./arch/x86/include/generated/uapi -I./arch/x86/include/generated -I./include -I./arch/x86/include/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/kconfig.h -Isamples/bpf \
-D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
-Wno-compare-distinct-pointer-types \
-Wno-gnu-variable-sized-type-not-at-end \
-Wno-address-of-packed-member -Wno-tautological-compare \
-Wno-unknown-warning-option \
-O2 -emit-llvm -c samples/bpf/tcp_synrto_kern.c -o -| llc -march=bpf -filetype=obj -o samples/bpf/tcp_synrto_kern.o
samples/bpf/tcp_synrto_kern.c:20:10: fatal error: 'bpf_endian.h' file not found
^~~~~~~~~~~~~~
1 error generated.
====
net has the same issue.
Add support for ntohl and htonl in tools/testing/selftests/bpf/bpf_endian.h.
Also move bpf_helpers.h from samples/bpf to selftests/bpf and change
compiler include logic so that programs in samples/bpf can access the headers
in selftests/bpf, but not the other way around.
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I noticed that test_l4lb was failing in selftests:
# ./test_progs
test_pkt_access:PASS:ipv4 77 nsec
test_pkt_access:PASS:ipv6 44 nsec
test_xdp:PASS:ipv4 2933 nsec
test_xdp:PASS:ipv6 1500 nsec
test_l4lb:PASS:ipv4 377 nsec
test_l4lb:PASS:ipv6 544 nsec
test_l4lb:FAIL:stats 6297600000 200000
test_tcp_estats:PASS: 0 nsec
Summary: 7 PASSED, 1 FAILED
Tracking down the issue actually revealed that endianness selection
in bpf_endian.h is broken when compiled with clang with bpf target.
test_pkt_access.c, test_l4lb.c is compiled with __BYTE_ORDER as
__BIG_ENDIAN, test_xdp.c as __LITTLE_ENDIAN! test_l4lb noticeably
fails, because the test accounts bytes via bpf_ntohs(ip6h->payload_len)
and bpf_ntohs(iph->tot_len), and compares them against a defined
value and given a wrong endianness, the test outcome is different,
of course.
Turns out that there are actually two bugs: i) when we do __BYTE_ORDER
comparison with __LITTLE_ENDIAN/__BIG_ENDIAN, then depending on the
include order we see different outcomes. Reason is that __BYTE_ORDER
is undefined due to missing endian.h include. Before we include the
asm/byteorder.h (e.g. through linux/in.h), then __BYTE_ORDER equals
__LITTLE_ENDIAN since both are undefined, after the include which
correctly pulls in linux/byteorder/little_endian.h, __LITTLE_ENDIAN
is defined, but given __BYTE_ORDER is still undefined, we match on
__BYTE_ORDER equals to __BIG_ENDIAN since __BIG_ENDIAN is also
undefined at that point, sigh. ii) But even that would be wrong,
since when compiling the test cases with clang, one can select between
bpfeb and bpfel targets for cross compilation. Hence, we can also not
rely on what the system's endian.h provides, but we need to look at
the compiler's defined endianness. The compiler defines __BYTE_ORDER__,
and we can match __ORDER_LITTLE_ENDIAN__ and __ORDER_BIG_ENDIAN__,
which also reflects targets bpf (native), bpfel, bpfeb correctly,
thus really only rely on that. After patch:
# ./test_progs
test_pkt_access:PASS:ipv4 74 nsec
test_pkt_access:PASS:ipv6 42 nsec
test_xdp:PASS:ipv4 2340 nsec
test_xdp:PASS:ipv6 1461 nsec
test_l4lb:PASS:ipv4 400 nsec
test_l4lb:PASS:ipv6 530 nsec
test_tcp_estats:PASS: 0 nsec
Summary: 7 PASSED, 0 FAILED
Fixes: 43bcf707cc ("bpf: fix _htons occurences in test_progs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We do not want to include things like stdio.h and friends into
eBPF program builds. bpf_util.h is for host compiled programs,
so eBPF C-code helpers don't really belong there.
Add a new bpf_endian.h as a quick fix for this for now.
Signed-off-by: David S. Miller <davem@davemloft.net>
