bpf: fix samples to add fake KBUILD_MODNAME

Some of the sample files are causing issues when they are loaded with tc
and cls_bpf, meaning tc bails out while trying to parse the resulting ELF
file as program/map/etc sections are not present, which can be easily
spotted with readelf(1).

Currently, BPF samples are including some of the kernel headers and mid
term we should change them to refrain from this, really. When dynamic
debugging is enabled, we bail out due to undeclared KBUILD_MODNAME, which
is easily overlooked in the build as clang spills this along with other
noisy warnings from various header includes, and llc still generates an
ELF file with mentioned characteristics. For just playing around with BPF
examples, this can be a bit of a hurdle to take.

Just add a fake KBUILD_MODNAME as a band-aid to fix the issue, same is
done in xdp*_kern samples already.

Fixes: 5fc8dfb94afc ("samples/bpf: add 'pointer to packet' tests")
Fixes: 67eca47f4039 ("samples/bpf: Add tunnel set/get tests.")
Fixes: e6c8cf7ac2fb ("cgroup: bpf: Add an example to do cgroup checking in BPF")
Reported-by: Chandrasekar Kannan <ckannan@console.to>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/samples/bpf/parse_ldabs.c b/samples/bpf/parse_ldabs.c
index d17550198d0628e063e43a64253ec335a012c28f..6db6b21fdc6dd71fd230cfbc40161d087c92024f 100644 (file)
--- a/samples/bpf/parse_ldabs.c
+++ b/samples/bpf/parse_ldabs.c
@@ -4,6 +4,7 @@
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
+#define KBUILD_MODNAME "foo"
 #include <linux/ip.h>
 #include <linux/ipv6.h>
 #include <linux/in.h>

diff --git a/samples/bpf/parse_simple.c b/samples/bpf/parse_simple.c
index cf2511c33905751bb6ed866bf6bba9b1fb8330f3..10af53d33cc2925a928fe496fdc1047629b998e3 100644 (file)
--- a/samples/bpf/parse_simple.c
+++ b/samples/bpf/parse_simple.c
@@ -4,6 +4,7 @@
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
+#define KBUILD_MODNAME "foo"
 #include <linux/ip.h>
 #include <linux/ipv6.h>
 #include <linux/in.h>

diff --git a/samples/bpf/parse_varlen.c b/samples/bpf/parse_varlen.c
index edab34dce79b3794b010ca4138ef969d13c68535..95c16324760c0be1af8be927e1adffae0b582525 100644 (file)
--- a/samples/bpf/parse_varlen.c
+++ b/samples/bpf/parse_varlen.c
@@ -4,6 +4,7 @@
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
+#define KBUILD_MODNAME "foo"
 #include <linux/if_ether.h>
 #include <linux/ip.h>
 #include <linux/ipv6.h>

diff --git a/samples/bpf/tcbpf1_kern.c b/samples/bpf/tcbpf1_kern.c
index fa051b3d53ee0a8f18da0b0701e04d2962c3e4b6..274c884c87fe01f28adae47feecb9de7f4f0948e 100644 (file)
--- a/samples/bpf/tcbpf1_kern.c
+++ b/samples/bpf/tcbpf1_kern.c
@@ -1,3 +1,4 @@
+#define KBUILD_MODNAME "foo"
 #include <uapi/linux/bpf.h>
 #include <uapi/linux/if_ether.h>
 #include <uapi/linux/if_packet.h>

diff --git a/samples/bpf/tcbpf2_kern.c b/samples/bpf/tcbpf2_kern.c
index 3303bb85593bc62a21afcf4f2864869a40543b4d..9c823a609e75f8d66bbe1fa31a1ecebac7f65311 100644 (file)
--- a/samples/bpf/tcbpf2_kern.c
+++ b/samples/bpf/tcbpf2_kern.c
@@ -5,6 +5,7 @@
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
+#define KBUILD_MODNAME "foo"
 #include <uapi/linux/bpf.h>
 #include <uapi/linux/if_ether.h>
 #include <uapi/linux/if_packet.h>

diff --git a/samples/bpf/test_cgrp2_tc_kern.c b/samples/bpf/test_cgrp2_tc_kern.c
index 10ff73404e3a80fe8bab464188335317ee71515a..1547b36a7b7b9bd5251dd1be6ae2a451cdca0a29 100644 (file)
--- a/samples/bpf/test_cgrp2_tc_kern.c
+++ b/samples/bpf/test_cgrp2_tc_kern.c
@@ -4,6 +4,7 @@
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
+#define KBUILD_MODNAME "foo"
 #include <uapi/linux/if_ether.h>
 #include <uapi/linux/in6.h>
 #include <uapi/linux/ipv6.h>