linux-stable.git/tools/lib/bpf, branch linux-5.4.y Linux kernel stable tree libbpf: Add NULL checks to bpf_object__{prev_map,next_map} 2024-09-12T09:03:54+00:00 Andreas Ziegler ziegler.andreas@siemens.com 2024-07-03T08:34:36+00:00 ed9cc6b6c36a8c96ba2382216806b1aef4fa538e [ Upstream commit cedc12c5b57f7efa6dbebfb2b140e8675f5a2616 ] In the current state, an erroneous call to bpf_object__find_map_by_name(NULL, ...) leads to a segmentation fault through the following call chain: bpf_object__find_map_by_name(obj = NULL, ...) -> bpf_object__for_each_map(pos, obj = NULL) -> bpf_object__next_map((obj = NULL), NULL) -> return (obj = NULL)->maps While calling bpf_object__find_map_by_name with obj = NULL is obviously incorrect, this should not lead to a segmentation fault but rather be handled gracefully. As __bpf_map__iter already handles this situation correctly, we can delegate the check for the regular case there and only add a check in case the prev or next parameter is NULL. Signed-off-by: Andreas Ziegler <ziegler.andreas@siemens.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20240703083436.505124-1-ziegler.andreas@siemens.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit cedc12c5b57f7efa6dbebfb2b140e8675f5a2616 ]

In the current state, an erroneous call to
bpf_object__find_map_by_name(NULL, ...) leads to a segmentation
fault through the following call chain:

  bpf_object__find_map_by_name(obj = NULL, ...)
  -> bpf_object__for_each_map(pos, obj = NULL)
  -> bpf_object__next_map((obj = NULL), NULL)
  -> return (obj = NULL)->maps

While calling bpf_object__find_map_by_name with obj = NULL is
obviously incorrect, this should not lead to a segmentation
fault but rather be handled gracefully.

As __bpf_map__iter already handles this situation correctly, we
can delegate the check for the regular case there and only add
a check in case the prev or next parameter is NULL.

Signed-off-by: Andreas Ziegler <ziegler.andreas@siemens.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240703083436.505124-1-ziegler.andreas@siemens.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
libbpf: Fix no-args func prototype BTF dumping syntax 2024-08-19T03:33:41+00:00 Andrii Nakryiko andrii@kernel.org 2024-07-12T22:44:42+00:00 6a8a0da4d84a4018c210c043d4331945a524ba29 [ Upstream commit 189f1a976e426011e6a5588f1d3ceedf71fe2965 ] For all these years libbpf's BTF dumper has been emitting not strictly valid syntax for function prototypes that have no input arguments. Instead of `int (*blah)()` we should emit `int (*blah)(void)`. This is not normally a problem, but it manifests when we get kfuncs in vmlinux.h that have no input arguments. Due to compiler internal specifics, we get no BTF information for such kfuncs, if they are not declared with proper `(void)`. The fix is trivial. We also need to adjust a few ancient tests that happily assumed `()` is correct. Fixes: 351131b51c7a ("libbpf: add btf_dump API for BTF-to-C conversion") Reported-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://lore.kernel.org/bpf/20240712224442.282823-1-andrii@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 189f1a976e426011e6a5588f1d3ceedf71fe2965 ]

For all these years libbpf's BTF dumper has been emitting not strictly
valid syntax for function prototypes that have no input arguments.

Instead of `int (*blah)()` we should emit `int (*blah)(void)`.

This is not normally a problem, but it manifests when we get kfuncs in
vmlinux.h that have no input arguments. Due to compiler internal
specifics, we get no BTF information for such kfuncs, if they are not
declared with proper `(void)`.

The fix is trivial. We also need to adjust a few ancient tests that
happily assumed `()` is correct.

Fixes: 351131b51c7a ("libbpf: add btf_dump API for BTF-to-C conversion")
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://lore.kernel.org/bpf/20240712224442.282823-1-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
libbpf: Fix alen calculation in libbpf_nla_dump_errormsg() 2023-03-11T15:43:41+00:00 Ilya Leoshkevich iii@linux.ibm.com 2023-02-10T00:12:01+00:00 291e6a68200822e74163c2ce53969e48861910fc [ Upstream commit 17bcd27a08a21397698edf143084d7c87ce17946 ] The code assumes that everything that comes after nlmsgerr are nlattrs. When calculating their size, it does not account for the initial nlmsghdr. This may lead to accessing uninitialized memory. Fixes: bbf48c18ee0c ("libbpf: add error reporting in XDP") Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230210001210.395194-8-iii@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 17bcd27a08a21397698edf143084d7c87ce17946 ]

The code assumes that everything that comes after nlmsgerr are nlattrs.
When calculating their size, it does not account for the initial
nlmsghdr. This may lead to accessing uninitialized memory.

Fixes: bbf48c18ee0c ("libbpf: add error reporting in XDP")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-8-iii@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
libbpf: Fix the name of a reused map 2022-08-25T09:17:43+00:00 Anquan Wu leiqi96@hotmail.com 2022-07-12T03:15:40+00:00 8ebe6121e7ccf2a6036b60bf9e2cbd5eb24d015f [ Upstream commit bf3f00378524adae16628cbadbd11ba7211863bb ] BPF map name is limited to BPF_OBJ_NAME_LEN. A map name is defined as being longer than BPF_OBJ_NAME_LEN, it will be truncated to BPF_OBJ_NAME_LEN when a userspace program calls libbpf to create the map. A pinned map also generates a path in the /sys. If the previous program wanted to reuse the map， it can not get bpf_map by name, because the name of the map is only partially the same as the name which get from pinned path. The syscall information below show that map name "process_pinned_map" is truncated to "process_pinned_". bpf(BPF_OBJ_GET, {pathname="/sys/fs/bpf/process_pinned_map", bpf_fd=0, file_flags=0}, 144) = -1 ENOENT (No such file or directory) bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_HASH, key_size=4, value_size=4,max_entries=1024, map_flags=0, inner_map_fd=0, map_name="process_pinned_",map_ifindex=0, btf_fd=3, btf_key_type_id=6, btf_value_type_id=10,btf_vmlinux_value_type_id=0}, 72) = 4 This patch check that if the name of pinned map are the same as the actual name for the first (BPF_OBJ_NAME_LEN - 1), bpf map still uses the name which is included in bpf object. Fixes: 26736eb9a483 ("tools: libbpf: allow map reuse") Signed-off-by: Anquan Wu <leiqi96@hotmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/OSZP286MB1725CEA1C95C5CB8E7CCC53FB8869@OSZP286MB1725.JPNP286.PROD.OUTLOOK.COM Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit bf3f00378524adae16628cbadbd11ba7211863bb ]

BPF map name is limited to BPF_OBJ_NAME_LEN.
A map name is defined as being longer than BPF_OBJ_NAME_LEN,
it will be truncated to BPF_OBJ_NAME_LEN when a userspace program
calls libbpf to create the map. A pinned map also generates a path
in the /sys. If the previous program wanted to reuse the map，
it can not get bpf_map by name, because the name of the map is only
partially the same as the name which get from pinned path.

The syscall information below show that map name "process_pinned_map"
is truncated to "process_pinned_".

    bpf(BPF_OBJ_GET, {pathname="/sys/fs/bpf/process_pinned_map",
    bpf_fd=0, file_flags=0}, 144) = -1 ENOENT (No such file or directory)

    bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_HASH, key_size=4,
    value_size=4,max_entries=1024, map_flags=0, inner_map_fd=0,
    map_name="process_pinned_",map_ifindex=0, btf_fd=3, btf_key_type_id=6,
    btf_value_type_id=10,btf_vmlinux_value_type_id=0}, 72) = 4

This patch check that if the name of pinned map are the same as the
actual name for the first (BPF_OBJ_NAME_LEN - 1),
bpf map still uses the name which is included in bpf object.

Fixes: 26736eb9a483 ("tools: libbpf: allow map reuse")
Signed-off-by: Anquan Wu <leiqi96@hotmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/OSZP286MB1725CEA1C95C5CB8E7CCC53FB8869@OSZP286MB1725.JPNP286.PROD.OUTLOOK.COM
Signed-off-by: Sasha Levin <sashal@kernel.org>
libbpf: Skip forward declaration when counting duplicated type names 2022-04-15T12:18:14+00:00 Xu Kuohai xukuohai@huawei.com 2022-03-01T05:32:49+00:00 3c660fa0f9052b9b0b3e4b804920011cb7caea9c [ Upstream commit 4226961b0019b2e1612029e8950a9e911affc995 ] Currently if a declaration appears in the BTF before the definition, the definition is dumped as a conflicting name, e.g.: $ bpftool btf dump file vmlinux format raw | grep "'unix_sock'" [81287] FWD 'unix_sock' fwd_kind=struct [89336] STRUCT 'unix_sock' size=1024 vlen=14 $ bpftool btf dump file vmlinux format c | grep "struct unix_sock" struct unix_sock; struct unix_sock___2 { <--- conflict, the "___2" is unexpected struct unix_sock___2 *unix_sk; This causes a compilation error if the dump output is used as a header file. Fix it by skipping declaration when counting duplicated type names. Fixes: 351131b51c7a ("libbpf: add btf_dump API for BTF-to-C conversion") Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20220301053250.1464204-2-xukuohai@huawei.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 4226961b0019b2e1612029e8950a9e911affc995 ]

Currently if a declaration appears in the BTF before the definition, the
definition is dumped as a conflicting name, e.g.:

    $ bpftool btf dump file vmlinux format raw | grep "'unix_sock'"
    [81287] FWD 'unix_sock' fwd_kind=struct
    [89336] STRUCT 'unix_sock' size=1024 vlen=14

    $ bpftool btf dump file vmlinux format c | grep "struct unix_sock"
    struct unix_sock;
    struct unix_sock___2 {	<--- conflict, the "___2" is unexpected
		    struct unix_sock___2 *unix_sk;

This causes a compilation error if the dump output is used as a header file.

Fix it by skipping declaration when counting duplicated type names.

Fixes: 351131b51c7a ("libbpf: add btf_dump API for BTF-to-C conversion")
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220301053250.1464204-2-xukuohai@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
libbpf: Fix BTF data layout checks and allow empty BTF 2021-11-17T08:48:39+00:00 Andrii Nakryiko andrii@kernel.org 2020-11-05T04:33:57+00:00 8fb436d146c75c2fe62c5909adadddaffd2c668b [ Upstream commit d8123624506cd62730c9cd9c7672c698e462703d ] Make data section layout checks stricter, disallowing overlap of types and strings data. Additionally, allow BTFs with no type data. There is nothing inherently wrong with having BTF with no types (put potentially with some strings). This could be a situation with kernel module BTFs, if module doesn't introduce any new type information. Also fix invalid offset alignment check for btf->hdr->type_off. Fixes: 8a138aed4a80 ("bpf: btf: Add BTF support to libbpf") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20201105043402.2530976-8-andrii@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit d8123624506cd62730c9cd9c7672c698e462703d ]

Make data section layout checks stricter, disallowing overlap of types and
strings data.

Additionally, allow BTFs with no type data. There is nothing inherently wrong
with having BTF with no types (put potentially with some strings). This could
be a situation with kernel module BTFs, if module doesn't introduce any new
type information.

Also fix invalid offset alignment check for btf->hdr->type_off.

Fixes: 8a138aed4a80 ("bpf: btf: Add BTF support to libbpf")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-8-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
libbpf: Fix BTF dump of pointer-to-array-of-struct 2021-03-30T12:35:27+00:00 Jean-Philippe Brucker jean-philippe@linaro.org 2021-03-19T11:25:54+00:00 4fda26d2f7e165a7cfab92fb7e3145973037ff02 [ Upstream commit 901ee1d750f29a335423eeb9463c3ca461ca18c2 ] The vmlinux.h generated from BTF is invalid when building drivers/phy/ti/phy-gmii-sel.c with clang: vmlinux.h:61702:27: error: array type has incomplete element type ‘struct reg_field’ 61702 | const struct reg_field (*regfields)[3]; | ^~~~~~~~~ bpftool generates a forward declaration for this struct regfield, which compilers aren't happy about. Here's a simplified reproducer: struct inner { int val; }; struct outer { struct inner (*ptr_to_array)[2]; } A; After build with clang -> bpftool btf dump c -> clang/gcc: ./def-clang.h:11:23: error: array has incomplete element type 'struct inner' struct inner (*ptr_to_array)[2]; Member ptr_to_array of struct outer is a pointer to an array of struct inner. In the DWARF generated by clang, struct outer appears before struct inner, so when converting BTF of struct outer into C, bpftool issues a forward declaration to struct inner. With GCC the DWARF info is reversed so struct inner gets fully defined. That forward declaration is not sufficient when compilers handle an array of the struct, even when it's only used through a pointer. Note that we can trigger the same issue with an intermediate typedef: struct inner { int val; }; typedef struct inner inner2_t[2]; struct outer { inner2_t *ptr_to_array; } A; Becomes: struct inner; typedef struct inner inner2_t[2]; And causes: ./def-clang.h:10:30: error: array has incomplete element type 'struct inner' typedef struct inner inner2_t[2]; To fix this, clear through_ptr whenever we encounter an intermediate array, to make the inner struct part of a strong link and force full declaration. Fixes: 351131b51c7a ("libbpf: add btf_dump API for BTF-to-C conversion") Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210319112554.794552-2-jean-philippe@linaro.org Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 901ee1d750f29a335423eeb9463c3ca461ca18c2 ]

The vmlinux.h generated from BTF is invalid when building
drivers/phy/ti/phy-gmii-sel.c with clang:

vmlinux.h:61702:27: error: array type has incomplete element type ‘struct reg_field’
61702 |  const struct reg_field (*regfields)[3];
      |                           ^~~~~~~~~

bpftool generates a forward declaration for this struct regfield, which
compilers aren't happy about. Here's a simplified reproducer:

	struct inner {
		int val;
	};
	struct outer {
		struct inner (*ptr_to_array)[2];
	} A;

After build with clang -> bpftool btf dump c -> clang/gcc:
./def-clang.h:11:23: error: array has incomplete element type 'struct inner'
        struct inner (*ptr_to_array)[2];

Member ptr_to_array of struct outer is a pointer to an array of struct
inner. In the DWARF generated by clang, struct outer appears before
struct inner, so when converting BTF of struct outer into C, bpftool
issues a forward declaration to struct inner. With GCC the DWARF info is
reversed so struct inner gets fully defined.

That forward declaration is not sufficient when compilers handle an
array of the struct, even when it's only used through a pointer. Note
that we can trigger the same issue with an intermediate typedef:

	struct inner {
	        int val;
	};
	typedef struct inner inner2_t[2];
	struct outer {
	        inner2_t *ptr_to_array;
	} A;

Becomes:

	struct inner;
	typedef struct inner inner2_t[2];

And causes:

./def-clang.h:10:30: error: array has incomplete element type 'struct inner'
	typedef struct inner inner2_t[2];

To fix this, clear through_ptr whenever we encounter an intermediate
array, to make the inner struct part of a strong link and force full
declaration.

Fixes: 351131b51c7a ("libbpf: add btf_dump API for BTF-to-C conversion")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210319112554.794552-2-jean-philippe@linaro.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
libbpf: Use SOCK_CLOEXEC when opening the netlink socket 2021-03-30T12:35:27+00:00 Kumar Kartikeya Dwivedi memxor@gmail.com 2021-03-17T11:58:58+00:00 e158238012297bfa601f417ac4d2b55118ccaeac [ Upstream commit 58bfd95b554f1a23d01228672f86bb489bdbf4ba ] Otherwise, there exists a small window between the opening and closing of the socket fd where it may leak into processes launched by some other thread. Fixes: 949abbe88436 ("libbpf: add function to setup XDP") Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20210317115857.6536-1-memxor@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 58bfd95b554f1a23d01228672f86bb489bdbf4ba ]

Otherwise, there exists a small window between the opening and closing
of the socket fd where it may leak into processes launched by some other
thread.

Fixes: 949abbe88436 ("libbpf: add function to setup XDP")
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210317115857.6536-1-memxor@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
libbpf: Fix INSTALL flag order 2021-03-30T12:35:24+00:00 Georgi Valkov gvalkov@abv.bg 2021-03-08T18:30:38+00:00 e64e327c7fab1c8ff80a5714932ec75a4ecf2a14 [ Upstream commit e7fb6465d4c8e767e39cbee72464e0060ab3d20c ] It was reported ([0]) that having optional -m flag between source and destination arguments in install command breaks bpftools cross-build on MacOS. Move -m to the front to fix this issue. [0] https://github.com/openwrt/openwrt/pull/3959 Fixes: 7110d80d53f4 ("libbpf: Makefile set specified permission mode") Signed-off-by: Georgi Valkov <gvalkov@abv.bg> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20210308183038.613432-1-andrii@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e7fb6465d4c8e767e39cbee72464e0060ab3d20c ]

It was reported ([0]) that having optional -m flag between source and
destination arguments in install command breaks bpftools cross-build
on MacOS. Move -m to the front to fix this issue.

  [0] https://github.com/openwrt/openwrt/pull/3959

Fixes: 7110d80d53f4 ("libbpf: Makefile set specified permission mode")
Signed-off-by: Georgi Valkov <gvalkov@abv.bg>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210308183038.613432-1-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
libbpf: Remove arch-specific include path in Makefile 2020-10-07T06:01:25+00:00 Naveen N. Rao naveen.n.rao@linux.vnet.ibm.com 2020-09-02T08:42:46+00:00 91d59157b10341c888edd4f91a0f677aa310693c [ Upstream commit 21e9ba5373fc2cec608fd68301a1dbfd14df3172 ] Ubuntu mainline builds for ppc64le are failing with the below error (*): CALL /home/kernel/COD/linux/scripts/atomic/check-atomics.sh DESCEND bpf/resolve_btfids Auto-detecting system features: ... libelf: [ [32mon[m ] ... zlib: [ [32mon[m ] ... bpf: [ [31mOFF[m ] BPF API too old make[6]: *** [Makefile:295: bpfdep] Error 1 make[5]: *** [Makefile:54: /home/kernel/COD/linux/debian/build/build-generic/tools/bpf/resolve_btfids//libbpf.a] Error 2 make[4]: *** [Makefile:71: bpf/resolve_btfids] Error 2 make[3]: *** [/home/kernel/COD/linux/Makefile:1890: tools/bpf/resolve_btfids] Error 2 make[2]: *** [/home/kernel/COD/linux/Makefile:335: __build_one_by_one] Error 2 make[2]: Leaving directory '/home/kernel/COD/linux/debian/build/build-generic' make[1]: *** [Makefile:185: __sub-make] Error 2 make[1]: Leaving directory '/home/kernel/COD/linux' resolve_btfids needs to be build as a host binary and it needs libbpf. However, libbpf Makefile hardcodes an include path utilizing $(ARCH). This results in mixing of cross-architecture headers resulting in a build failure. The specific header include path doesn't seem necessary for a libbpf build. Hence, remove the same. (*) https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.9-rc3/ppc64el/log Reported-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200902084246.1513055-1-naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 21e9ba5373fc2cec608fd68301a1dbfd14df3172 ]

Ubuntu mainline builds for ppc64le are failing with the below error (*):
    CALL    /home/kernel/COD/linux/scripts/atomic/check-atomics.sh
    DESCEND  bpf/resolve_btfids

  Auto-detecting system features:
  ...                        libelf: [ [32mon[m  ]
  ...                          zlib: [ [32mon[m  ]
  ...                           bpf: [ [31mOFF[m ]

  BPF API too old
  make[6]: *** [Makefile:295: bpfdep] Error 1
  make[5]: *** [Makefile:54: /home/kernel/COD/linux/debian/build/build-generic/tools/bpf/resolve_btfids//libbpf.a] Error 2
  make[4]: *** [Makefile:71: bpf/resolve_btfids] Error 2
  make[3]: *** [/home/kernel/COD/linux/Makefile:1890: tools/bpf/resolve_btfids] Error 2
  make[2]: *** [/home/kernel/COD/linux/Makefile:335: __build_one_by_one] Error 2
  make[2]: Leaving directory '/home/kernel/COD/linux/debian/build/build-generic'
  make[1]: *** [Makefile:185: __sub-make] Error 2
  make[1]: Leaving directory '/home/kernel/COD/linux'

resolve_btfids needs to be build as a host binary and it needs libbpf.
However, libbpf Makefile hardcodes an include path utilizing $(ARCH).
This results in mixing of cross-architecture headers resulting in a
build failure.

The specific header include path doesn't seem necessary for a libbpf
build. Hence, remove the same.

(*) https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.9-rc3/ppc64el/log

Reported-by: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200902084246.1513055-1-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>