2023-01-16 05:28:59

by Tiezhu Yang

[permalink] [raw]
Subject: [PATCH bpf-next] selftests/bpf: Fix undeclared identifier build errors of test_bpf_nf.c

$ make -C tools/testing/selftests/bpf/

CLNG-BPF [test_maps] test_bpf_nf.bpf.o
progs/test_bpf_nf.c:160:42: error: use of undeclared identifier 'NF_NAT_MANIP_SRC'
bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
^
progs/test_bpf_nf.c:163:42: error: use of undeclared identifier 'NF_NAT_MANIP_DST'
bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
^
2 errors generated.

Copy the definitions in include/net/netfilter/nf_nat.h to test_bpf_nf.c
to fix the above build errors.

Fixes: b06b45e82b59 ("selftests/bpf: add tests for bpf_ct_set_nat_info kfunc")
Signed-off-by: Tiezhu Yang <[email protected]>
---
tools/testing/selftests/bpf/progs/test_bpf_nf.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
index 227e85e..114f961 100644
--- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
+++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
@@ -34,6 +34,11 @@ __be16 dport = 0;
int test_exist_lookup = -ENOENT;
u32 test_exist_lookup_mark = 0;

+enum nf_nat_manip_type {
+ NF_NAT_MANIP_SRC,
+ NF_NAT_MANIP_DST
+};
+
struct nf_conn;

struct bpf_ct_opts___local {
--
2.1.0


2023-01-16 13:06:17

by Eduard Zingerman

[permalink] [raw]
Subject: Re: [PATCH bpf-next] selftests/bpf: Fix undeclared identifier build errors of test_bpf_nf.c

On Mon, 2023-01-16 at 12:55 +0800, Tiezhu Yang wrote:
> $ make -C tools/testing/selftests/bpf/
>
> CLNG-BPF [test_maps] test_bpf_nf.bpf.o
> progs/test_bpf_nf.c:160:42: error: use of undeclared identifier 'NF_NAT_MANIP_SRC'
> bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
> ^
> progs/test_bpf_nf.c:163:42: error: use of undeclared identifier 'NF_NAT_MANIP_DST'
> bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
> ^
> 2 errors generated.
>
> Copy the definitions in include/net/netfilter/nf_nat.h to test_bpf_nf.c
> to fix the above build errors.
>
> Fixes: b06b45e82b59 ("selftests/bpf: add tests for bpf_ct_set_nat_info kfunc")
> Signed-off-by: Tiezhu Yang <[email protected]>
> ---
> tools/testing/selftests/bpf/progs/test_bpf_nf.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
> index 227e85e..114f961 100644
> --- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
> +++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
> @@ -34,6 +34,11 @@ __be16 dport = 0;
> int test_exist_lookup = -ENOENT;
> u32 test_exist_lookup_mark = 0;
>
> +enum nf_nat_manip_type {
> + NF_NAT_MANIP_SRC,
> + NF_NAT_MANIP_DST
> +};
> +

This is confusing, when I build the kernel/tests I get the declaration of
the "enum nf_nat_manip_type" from the vmlinux.h (which is included from test_bpf_nf.c).
Which means that this patch results in compilation error with my configuration.
Is there a chance that your kernel is configured without some necessary netfilter
configuration options? Have you tried this patch with BPF CI?

> struct nf_conn;
>
> struct bpf_ct_opts___local {

2023-01-16 14:43:22

by Alan Maguire

[permalink] [raw]
Subject: Re: [PATCH bpf-next] selftests/bpf: Fix undeclared identifier build errors of test_bpf_nf.c

On 16/01/2023 12:30, Eduard Zingerman wrote:
> On Mon, 2023-01-16 at 12:55 +0800, Tiezhu Yang wrote:
>> $ make -C tools/testing/selftests/bpf/
>>
>> CLNG-BPF [test_maps] test_bpf_nf.bpf.o
>> progs/test_bpf_nf.c:160:42: error: use of undeclared identifier 'NF_NAT_MANIP_SRC'
>> bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
>> ^
>> progs/test_bpf_nf.c:163:42: error: use of undeclared identifier 'NF_NAT_MANIP_DST'
>> bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
>> ^
>> 2 errors generated.
>>
>> Copy the definitions in include/net/netfilter/nf_nat.h to test_bpf_nf.c
>> to fix the above build errors.
>>
>> Fixes: b06b45e82b59 ("selftests/bpf: add tests for bpf_ct_set_nat_info kfunc")
>> Signed-off-by: Tiezhu Yang <[email protected]>
>> ---
>> tools/testing/selftests/bpf/progs/test_bpf_nf.c | 5 +++++
>> 1 file changed, 5 insertions(+)
>>
>> diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>> index 227e85e..114f961 100644
>> --- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>> +++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>> @@ -34,6 +34,11 @@ __be16 dport = 0;
>> int test_exist_lookup = -ENOENT;
>> u32 test_exist_lookup_mark = 0;
>>
>> +enum nf_nat_manip_type {
>> + NF_NAT_MANIP_SRC,
>> + NF_NAT_MANIP_DST
>> +};
>> +
>
> This is confusing, when I build the kernel/tests I get the declaration
> the "enum nf_nat_manip_type" from the vmlinux.h (which is included from test_bpf_nf.c).
> Which means that this patch results in compilation error with my configuration.
> Is there a chance that your kernel is configured without some necessary netfilter
> configuration options? Have you tried this patch with BPF CI?
>

Yep; I suspect if CONFIG_NF_NAT=m , the required definitions won't make it
into vmlinux.h. The reference tools/testing/seftests/bpf/config has
CONFIG_NF_NAT=y so it is at least documented in the referenced config.

I'd suggest going the route of

commit aa67961f3243dfff26c47769f87b4d94b07ec71f
Author: Martin KaFai Lau <[email protected]>
Date: Tue Dec 6 11:35:54 2022 -0800

selftests/bpf: Allow building bpf tests with CONFIG_XFRM_INTERFACE=[m|n]

...and adding/using local definitons like:

enum nf_nat_manip_type_local {
NF_NAT_MANIP_SRC_LOCAL,
NF_NAT_MANIP_DST_LOCAL
};

...to avoid the name clash.


Alan

2023-01-17 07:27:59

by Yonghong Song

[permalink] [raw]
Subject: Re: [PATCH bpf-next] selftests/bpf: Fix undeclared identifier build errors of test_bpf_nf.c



On 1/16/23 5:54 AM, Alan Maguire wrote:
> On 16/01/2023 12:30, Eduard Zingerman wrote:
>> On Mon, 2023-01-16 at 12:55 +0800, Tiezhu Yang wrote:
>>> $ make -C tools/testing/selftests/bpf/
>>>
>>> CLNG-BPF [test_maps] test_bpf_nf.bpf.o
>>> progs/test_bpf_nf.c:160:42: error: use of undeclared identifier 'NF_NAT_MANIP_SRC'
>>> bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
>>> ^
>>> progs/test_bpf_nf.c:163:42: error: use of undeclared identifier 'NF_NAT_MANIP_DST'
>>> bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
>>> ^
>>> 2 errors generated.
>>>
>>> Copy the definitions in include/net/netfilter/nf_nat.h to test_bpf_nf.c
>>> to fix the above build errors.
>>>
>>> Fixes: b06b45e82b59 ("selftests/bpf: add tests for bpf_ct_set_nat_info kfunc")
>>> Signed-off-by: Tiezhu Yang <[email protected]>
>>> ---
>>> tools/testing/selftests/bpf/progs/test_bpf_nf.c | 5 +++++
>>> 1 file changed, 5 insertions(+)
>>>
>>> diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>> index 227e85e..114f961 100644
>>> --- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>> +++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>> @@ -34,6 +34,11 @@ __be16 dport = 0;
>>> int test_exist_lookup = -ENOENT;
>>> u32 test_exist_lookup_mark = 0;
>>>
>>> +enum nf_nat_manip_type {
>>> + NF_NAT_MANIP_SRC,
>>> + NF_NAT_MANIP_DST
>>> +};
>>> +
>>
>> This is confusing, when I build the kernel/tests I get the declaration
>> the "enum nf_nat_manip_type" from the vmlinux.h (which is included from test_bpf_nf.c).
>> Which means that this patch results in compilation error with my configuration.
>> Is there a chance that your kernel is configured without some necessary netfilter
>> configuration options? Have you tried this patch with BPF CI?
>>
>
> Yep; I suspect if CONFIG_NF_NAT=m , the required definitions won't make it
> into vmlinux.h. The reference tools/testing/seftests/bpf/config has
> CONFIG_NF_NAT=y so it is at least documented in the referenced config.
>
> I'd suggest going the route of
>
> commit aa67961f3243dfff26c47769f87b4d94b07ec71f
> Author: Martin KaFai Lau <[email protected]>
> Date: Tue Dec 6 11:35:54 2022 -0800
>
> selftests/bpf: Allow building bpf tests with CONFIG_XFRM_INTERFACE=[m|n]
>
> ...and adding/using local definitons like:
>
> enum nf_nat_manip_type_local {
> NF_NAT_MANIP_SRC_LOCAL,
> NF_NAT_MANIP_DST_LOCAL
> };

The above won't support core, and since preserve_access_index attribute
does not support enum for now. We need to use bpf_core_enum_value to
retrieve the proper value through CORE.

could you try the following?

enum nf_nat_manip_type___local {
NF_NAT_MANIP_SRC___LOCAL,
NF_NAT_MANIP_DST___LOCAL,
};

...
bpf_ct_set_nat_info(ct, &saddr, sport, bpf_core_enum_value(enum
nf_nat_manip_type___local, NF_NAT_MANIP_SRC___LOCAL));
...

bpf_ct_set_nat_info(ct, &daddr, dport, bpf_core_enum_value(enum
nf_nat_manip_type___local, NF_NAT_MANIP_DST___LOCAL));

whether it works or not? Could you also try if the
enumerator sequence in enum nf_nat_manip_type___local changed?

>
> ...to avoid the name clash.
>
>
> Alan

2023-01-17 10:31:20

by Tiezhu Yang

[permalink] [raw]
Subject: Re: [PATCH bpf-next] selftests/bpf: Fix undeclared identifier build errors of test_bpf_nf.c



On 01/17/2023 02:48 PM, Yonghong Song wrote:
>
>
> On 1/16/23 5:54 AM, Alan Maguire wrote:
>> On 16/01/2023 12:30, Eduard Zingerman wrote:
>>> On Mon, 2023-01-16 at 12:55 +0800, Tiezhu Yang wrote:
>>>> $ make -C tools/testing/selftests/bpf/
>>>>
>>>> CLNG-BPF [test_maps] test_bpf_nf.bpf.o
>>>> progs/test_bpf_nf.c:160:42: error: use of undeclared identifier
>>>> 'NF_NAT_MANIP_SRC'
>>>> bpf_ct_set_nat_info(ct, &saddr, sport,
>>>> NF_NAT_MANIP_SRC);
>>>> ^
>>>> progs/test_bpf_nf.c:163:42: error: use of undeclared identifier
>>>> 'NF_NAT_MANIP_DST'
>>>> bpf_ct_set_nat_info(ct, &daddr, dport,
>>>> NF_NAT_MANIP_DST);
>>>> ^
>>>> 2 errors generated.
>>>>
>>>> Copy the definitions in include/net/netfilter/nf_nat.h to test_bpf_nf.c
>>>> to fix the above build errors.
>>>>
>>>> Fixes: b06b45e82b59 ("selftests/bpf: add tests for
>>>> bpf_ct_set_nat_info kfunc")
>>>> Signed-off-by: Tiezhu Yang <[email protected]>
>>>> ---
>>>> tools/testing/selftests/bpf/progs/test_bpf_nf.c | 5 +++++
>>>> 1 file changed, 5 insertions(+)
>>>>
>>>> diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>> b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>> index 227e85e..114f961 100644
>>>> --- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>> +++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>> @@ -34,6 +34,11 @@ __be16 dport = 0;
>>>> int test_exist_lookup = -ENOENT;
>>>> u32 test_exist_lookup_mark = 0;
>>>> +enum nf_nat_manip_type {
>>>> + NF_NAT_MANIP_SRC,
>>>> + NF_NAT_MANIP_DST
>>>> +};
>>>> +
>>>
>>> This is confusing, when I build the kernel/tests I get the declaration
>>> the "enum nf_nat_manip_type" from the vmlinux.h (which is included
>>> from test_bpf_nf.c).
>>> Which means that this patch results in compilation error with my
>>> configuration.
>>> Is there a chance that your kernel is configured without some
>>> necessary netfilter
>>> configuration options? Have you tried this patch with BPF CI?
>>>
>>
>> Yep; I suspect if CONFIG_NF_NAT=m , the required definitions won't
>> make it
>> into vmlinux.h. The reference tools/testing/seftests/bpf/config has
>> CONFIG_NF_NAT=y so it is at least documented in the referenced config.
>>
>> I'd suggest going the route of
>>
>> commit aa67961f3243dfff26c47769f87b4d94b07ec71f
>> Author: Martin KaFai Lau <[email protected]>
>> Date: Tue Dec 6 11:35:54 2022 -0800
>>
>> selftests/bpf: Allow building bpf tests with
>> CONFIG_XFRM_INTERFACE=[m|n]
>> ...and adding/using local definitons like:
>>
>> enum nf_nat_manip_type_local {
>> NF_NAT_MANIP_SRC_LOCAL,
>> NF_NAT_MANIP_DST_LOCAL
>> };
>
> The above won't support core, and since preserve_access_index attribute
> does not support enum for now. We need to use bpf_core_enum_value to
> retrieve the proper value through CORE.
>
> could you try the following?
>
> enum nf_nat_manip_type___local {
> NF_NAT_MANIP_SRC___LOCAL,
> NF_NAT_MANIP_DST___LOCAL,
> };

This is OK, it is similar with commit 1058b6a78db2 ("selftests/bpf: Do
not fail build if CONFIG_NF_CONNTRACK=m/n").

>
> ...
> bpf_ct_set_nat_info(ct, &saddr, sport, bpf_core_enum_value(enum
> nf_nat_manip_type___local, NF_NAT_MANIP_SRC___LOCAL));
> ...
>
> bpf_ct_set_nat_info(ct, &daddr, dport, bpf_core_enum_value(enum
> nf_nat_manip_type___local, NF_NAT_MANIP_DST___LOCAL));
>
> whether it works or not? Could you also try if the
> enumerator sequence in enum nf_nat_manip_type___local changed?
>
>>
>> ...to avoid the name clash.
>>
>>
>> Alan

I tested this on x86_64 fedora 36, using config-5.17.5-300.fc36.x86_64
to generate .config, CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=m, there are
no definitions of NF_NAT_MANIP_SRC and NF_NAT_MANIP_DST in vmlinux.h,
build test_bpf_nf.c failed.

$ grep -w CONFIG_NF_CONNTRACK /boot/config-5.17.5-300.fc36.x86_64
CONFIG_NF_CONNTRACK=m
$ grep -w CONFIG_NF_NAT /boot/config-5.17.5-300.fc36.x86_64
CONFIG_NF_NAT=m

I tested with various configs, the definitions of NF_NAT_MANIP_SRC and
NF_NAT_MANIP_DST in vmlinux.h only depend on CONFIG_NF_CONNTRACK=y.

(1) CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=m, no definitions
$ grep -w CONFIG_NF_CONNTRACK .config
CONFIG_NF_CONNTRACK=m
$ grep -w CONFIG_NF_NAT .config
CONFIG_NF_NAT=m
$ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
$ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
$

(2) CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=y, no definitions
This case is unable, because CONFIG_NF_NAT depends on CONFIG_NF_CONNTRACK.

(3) CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=n, no definitions
$ grep -w CONFIG_NF_CONNTRACK .config
CONFIG_NF_CONNTRACK=m
$ grep -w CONFIG_NF_NAT .config
# CONFIG_NF_NAT is not set
$ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
$ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
$

(4) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=m, have definitions
$ grep -w CONFIG_NF_CONNTRACK .config
CONFIG_NF_CONNTRACK=y
$ grep -w CONFIG_NF_NAT .config
CONFIG_NF_NAT=m
$ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
NF_NAT_MANIP_SRC = 0,
$ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
NF_NAT_MANIP_DST = 1,

(5) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=y, have definitions
$ grep -w CONFIG_NF_CONNTRACK .config
CONFIG_NF_CONNTRACK=y
$ grep -w CONFIG_NF_NAT .config
CONFIG_NF_NAT=y
$ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
NF_NAT_MANIP_SRC = 0,
$ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
NF_NAT_MANIP_DST = 1,

(6) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=n, have definitions
$ grep -w CONFIG_NF_CONNTRACK .config
CONFIG_NF_CONNTRACK=y
$ grep -w CONFIG_NF_NAT .config
# CONFIG_NF_NAT is not set
$ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
NF_NAT_MANIP_SRC = 0,
$ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
NF_NAT_MANIP_DST = 1,

(7) CONFIG_NF_CONNTRACK=n, CONFIG_NF_NAT=n, no definitions
$ grep -w CONFIG_NF_CONNTRACK .config
# CONFIG_NF_CONNTRACK is not set
$ grep -w CONFIG_NF_NAT .config
$ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
$ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
$

(8) CONFIG_NF_CONNTRACK=n, CONFIG_NF_NAT=y, no definitions
This case is unable, because CONFIG_NF_NAT depends on CONFIG_NF_CONNTRACK.

Here is an alternative change to check whether CONFIG_NF_CONNTRACK
is m, enum nf_nat_manip_type___local is simple, which one is better?

$ git diff tools/testing/selftests/bpf/
diff --git a/tools/testing/selftests/bpf/Makefile
b/tools/testing/selftests/bpf/Makefile
index 22533a18705e..f3cf02046c20 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -325,7 +325,7 @@ endif

CLANG_SYS_INCLUDES = $(call
get_sys_includes,$(CLANG),$(CLANG_TARGET_ARCH))
BPF_CFLAGS = -g -Werror -D__TARGET_ARCH_$(SRCARCH) $(MENDIAN) \
- -I$(INCLUDE_DIR) -I$(CURDIR) -I$(APIDIR) \
+ -I$(INCLUDE_DIR) -I$(CURDIR) -I$(APIDIR) -I$(TOOLSINCDIR) \
-I$(abspath $(OUTPUT)/../usr/include)

CLANG_CFLAGS = $(CLANG_SYS_INCLUDES) \
diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
index 227e85e85dda..f2101807072f 100644
--- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
+++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
@@ -2,6 +2,7 @@
#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_endian.h>
+#include <linux/kconfig.h>

#define EAFNOSUPPORT 97
#define EPROTO 71
@@ -34,6 +35,13 @@ __be16 dport = 0;
int test_exist_lookup = -ENOENT;
u32 test_exist_lookup_mark = 0;

+#if IS_MODULE(CONFIG_NF_CONNTRACK)
+enum nf_nat_manip_type {
+ NF_NAT_MANIP_SRC,
+ NF_NAT_MANIP_DST
+};
+#endif
+
struct nf_conn;

struct bpf_ct_opts___local {

Note that when unset CONFIG_NF_CONNTRACK, there are much more
build errors, I do not know whether it is necessary to fix it
and how to fix it properly. Here, I only consider the failed
case CONFIG_NF_CONNTRACK=m.

Thanks,
Tiezhu

2023-01-17 19:38:16

by Yonghong Song

[permalink] [raw]
Subject: Re: [PATCH bpf-next] selftests/bpf: Fix undeclared identifier build errors of test_bpf_nf.c



On 1/17/23 1:52 AM, Tiezhu Yang wrote:
>
>
> On 01/17/2023 02:48 PM, Yonghong Song wrote:
>>
>>
>> On 1/16/23 5:54 AM, Alan Maguire wrote:
>>> On 16/01/2023 12:30, Eduard Zingerman wrote:
>>>> On Mon, 2023-01-16 at 12:55 +0800, Tiezhu Yang wrote:
>>>>> $ make -C tools/testing/selftests/bpf/
>>>>>
>>>>>    CLNG-BPF [test_maps] test_bpf_nf.bpf.o
>>>>> progs/test_bpf_nf.c:160:42: error: use of undeclared identifier
>>>>> 'NF_NAT_MANIP_SRC'
>>>>>                  bpf_ct_set_nat_info(ct, &saddr, sport,
>>>>> NF_NAT_MANIP_SRC);
>>>>>                                                         ^
>>>>> progs/test_bpf_nf.c:163:42: error: use of undeclared identifier
>>>>> 'NF_NAT_MANIP_DST'
>>>>>                  bpf_ct_set_nat_info(ct, &daddr, dport,
>>>>> NF_NAT_MANIP_DST);
>>>>>                                                         ^
>>>>> 2 errors generated.
>>>>>
>>>>> Copy the definitions in include/net/netfilter/nf_nat.h to
>>>>> test_bpf_nf.c
>>>>> to fix the above build errors.
>>>>>
>>>>> Fixes: b06b45e82b59 ("selftests/bpf: add tests for
>>>>> bpf_ct_set_nat_info kfunc")
>>>>> Signed-off-by: Tiezhu Yang <[email protected]>
>>>>> ---
>>>>>   tools/testing/selftests/bpf/progs/test_bpf_nf.c | 5 +++++
>>>>>   1 file changed, 5 insertions(+)
>>>>>
>>>>> diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>>> b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>>> index 227e85e..114f961 100644
>>>>> --- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>>> +++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>>> @@ -34,6 +34,11 @@ __be16 dport = 0;
>>>>>   int test_exist_lookup = -ENOENT;
>>>>>   u32 test_exist_lookup_mark = 0;
>>>>>   +enum nf_nat_manip_type {
>>>>> +    NF_NAT_MANIP_SRC,
>>>>> +    NF_NAT_MANIP_DST
>>>>> +};
>>>>> +
>>>>
>>>> This is confusing, when I build the kernel/tests I get the declaration
>>>> the "enum nf_nat_manip_type" from the vmlinux.h (which is included
>>>> from test_bpf_nf.c).
>>>> Which means that this patch results in compilation error with my
>>>> configuration.
>>>> Is there a chance that your kernel is configured without some
>>>> necessary netfilter
>>>> configuration options? Have you tried this patch with BPF CI?
>>>>
>>>
>>> Yep; I suspect if CONFIG_NF_NAT=m , the required definitions won't
>>> make it
>>> into vmlinux.h. The reference tools/testing/seftests/bpf/config has
>>> CONFIG_NF_NAT=y so it is at least documented in the referenced config.
>>>
>>> I'd suggest going the route of
>>>
>>> commit aa67961f3243dfff26c47769f87b4d94b07ec71f
>>> Author: Martin KaFai Lau <[email protected]>
>>> Date:   Tue Dec 6 11:35:54 2022 -0800
>>>
>>>      selftests/bpf: Allow building bpf tests with
>>> CONFIG_XFRM_INTERFACE=[m|n]
>>>      ...and adding/using local definitons like:
>>>
>>> enum nf_nat_manip_type_local {
>>>     NF_NAT_MANIP_SRC_LOCAL,
>>>     NF_NAT_MANIP_DST_LOCAL
>>> };
>>
>> The above won't support core, and since preserve_access_index attribute
>> does not support enum for now. We need to use bpf_core_enum_value to
>> retrieve the proper value through CORE.
>>
>> could you try the following?
>>
>> enum nf_nat_manip_type___local {
>>     NF_NAT_MANIP_SRC___LOCAL,
>>     NF_NAT_MANIP_DST___LOCAL,
>> };
>
> This is OK, it is similar with commit 1058b6a78db2 ("selftests/bpf: Do
> not fail build if CONFIG_NF_CONNTRACK=m/n").
>
>>
>> ...
>> bpf_ct_set_nat_info(ct, &saddr, sport, bpf_core_enum_value(enum
>> nf_nat_manip_type___local,  NF_NAT_MANIP_SRC___LOCAL));
>> ...
>>
>> bpf_ct_set_nat_info(ct, &daddr, dport, bpf_core_enum_value(enum
>> nf_nat_manip_type___local,  NF_NAT_MANIP_DST___LOCAL));
>>
>> whether it works or not? Could you also try if the
>> enumerator sequence in enum nf_nat_manip_type___local changed?
>>
>>>
>>> ...to avoid the name clash.
>>>
>>>
>>> Alan
>
> I tested this on x86_64 fedora 36, using config-5.17.5-300.fc36.x86_64
> to generate .config, CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=m, there are
> no definitions of NF_NAT_MANIP_SRC and NF_NAT_MANIP_DST in vmlinux.h,
> build test_bpf_nf.c failed.

Thanks for trying. Yes, I tried in my environment and it failed because
I didn't change the enum nf_nat_manip_type type for kfunc:
int bpf_ct_set_nat_info(struct nf_conn *, union nf_inet_addr *,
int port, enum nf_nat_manip_type) __ksym;

But when I changed 'enum nf_nat_manip_type' to
'enum nf_nat_manip_type___local', kernel complains kfunc argument
mismatch. The reason most likely is 'enum nf_nat_manip_type___local'
is not converted to 'enum nf_nat_manip_type' by libbpf.

This might be expected as preserve_access_index attribute only
supports record (struct/union) type and libbpf might just do that.
Could you double check whether this is the case or not?

Maybe it is time to implement preserve_access_index support
for enum type in clang now.

But we need to resolve the issue, even temporarily for now.
See below.

>
> $ grep -w CONFIG_NF_CONNTRACK /boot/config-5.17.5-300.fc36.x86_64
> CONFIG_NF_CONNTRACK=m
> $ grep -w CONFIG_NF_NAT /boot/config-5.17.5-300.fc36.x86_64
> CONFIG_NF_NAT=m
>
> I tested with various configs, the definitions of NF_NAT_MANIP_SRC and
> NF_NAT_MANIP_DST in vmlinux.h only depend on CONFIG_NF_CONNTRACK=y.
>
> (1) CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=m, no definitions
> $ grep -w CONFIG_NF_CONNTRACK .config
> CONFIG_NF_CONNTRACK=m
> $ grep -w CONFIG_NF_NAT .config
> CONFIG_NF_NAT=m
> $ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
> $ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
> $
>
> (2) CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=y, no definitions
> This case is unable, because CONFIG_NF_NAT depends on CONFIG_NF_CONNTRACK.
>
> (3) CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=n, no definitions
> $ grep -w CONFIG_NF_CONNTRACK .config
> CONFIG_NF_CONNTRACK=m
> $ grep -w CONFIG_NF_NAT .config
> # CONFIG_NF_NAT is not set
> $ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
> $ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
> $
>
> (4) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=m, have definitions
> $ grep -w CONFIG_NF_CONNTRACK .config
> CONFIG_NF_CONNTRACK=y
> $ grep -w CONFIG_NF_NAT .config
> CONFIG_NF_NAT=m
> $ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
>     NF_NAT_MANIP_SRC = 0,
> $ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
>     NF_NAT_MANIP_DST = 1,
>
> (5) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=y, have definitions
> $ grep -w CONFIG_NF_CONNTRACK .config
> CONFIG_NF_CONNTRACK=y
> $ grep -w CONFIG_NF_NAT .config
> CONFIG_NF_NAT=y
> $ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
>     NF_NAT_MANIP_SRC = 0,
> $ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
>     NF_NAT_MANIP_DST = 1,
>
> (6) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=n, have definitions
> $ grep -w CONFIG_NF_CONNTRACK .config
> CONFIG_NF_CONNTRACK=y
> $ grep -w CONFIG_NF_NAT .config
> # CONFIG_NF_NAT is not set
> $ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
>     NF_NAT_MANIP_SRC = 0,
> $ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
>     NF_NAT_MANIP_DST = 1,
>
> (7) CONFIG_NF_CONNTRACK=n, CONFIG_NF_NAT=n, no definitions
> $ grep -w CONFIG_NF_CONNTRACK .config
> # CONFIG_NF_CONNTRACK is not set
> $ grep -w CONFIG_NF_NAT .config
> $ grep NF_NAT_MANIP_SRC tools/testing/selftests/bpf/tools/include/vmlinux.h
> $ grep NF_NAT_MANIP_DST tools/testing/selftests/bpf/tools/include/vmlinux.h
> $
>
> (8) CONFIG_NF_CONNTRACK=n, CONFIG_NF_NAT=y, no definitions
> This case is unable, because CONFIG_NF_NAT depends on CONFIG_NF_CONNTRACK.
>
> Here is an alternative change to check whether CONFIG_NF_CONNTRACK
> is m, enum nf_nat_manip_type___local is simple, which one is better?
>
> $ git diff tools/testing/selftests/bpf/
> diff --git a/tools/testing/selftests/bpf/Makefile
> b/tools/testing/selftests/bpf/Makefile
> index 22533a18705e..f3cf02046c20 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -325,7 +325,7 @@ endif
>
>  CLANG_SYS_INCLUDES = $(call
> get_sys_includes,$(CLANG),$(CLANG_TARGET_ARCH))
>  BPF_CFLAGS = -g -Werror -D__TARGET_ARCH_$(SRCARCH) $(MENDIAN)          \
> -            -I$(INCLUDE_DIR) -I$(CURDIR) -I$(APIDIR)                   \
> +            -I$(INCLUDE_DIR) -I$(CURDIR) -I$(APIDIR) -I$(TOOLSINCDIR)  \
>              -I$(abspath $(OUTPUT)/../usr/include)
>
>  CLANG_CFLAGS = $(CLANG_SYS_INCLUDES) \
> diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
> b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
> index 227e85e85dda..f2101807072f 100644
> --- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
> +++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
> @@ -2,6 +2,7 @@
>  #include <vmlinux.h>
>  #include <bpf/bpf_helpers.h>
>  #include <bpf/bpf_endian.h>
> +#include <linux/kconfig.h>
>
>  #define EAFNOSUPPORT 97
>  #define EPROTO 71
> @@ -34,6 +35,13 @@ __be16 dport = 0;
>  int test_exist_lookup = -ENOENT;
>  u32 test_exist_lookup_mark = 0;
>
> +#if IS_MODULE(CONFIG_NF_CONNTRACK)
> +enum nf_nat_manip_type {
> +       NF_NAT_MANIP_SRC,
> +       NF_NAT_MANIP_DST
> +};
> +#endif
> +

The above change does not work for me. The complication failed with

CLNG-BPF [test_maps]
btf__core_reloc_nesting___err_missing_container.bpf.o
CLNG-BPF [test_maps] test_sysctl_loop2.bpf.o
progs/test_bpf_nf.c:168:42: error: use of undeclared identifier
'NF_NAT_MANIP_SRC'
bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
^
progs/test_bpf_nf.c:171:42: error: use of undeclared identifier
'NF_NAT_MANIP_DST'
bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
^
2 errors generated.


Apparently, IS_MODULE(...) is recognized but it returns 0.
I do have CONFIG_NF_CONNTRACK=m in my config.
Note that I build the kernel with KBUILD_OUTPUT=<another dir>
(make -j LLVM=1) so vmlinux is in a different place.
While I build selftest
with 'make -C tools/testing/selftests/bpf -j LLVM=1' which
is in-tree.

>  struct nf_conn;
>
>  struct bpf_ct_opts___local {
>
> Note that when unset CONFIG_NF_CONNTRACK, there are much more
> build errors, I do not know whether it is necessary to fix it
> and how to fix it properly. Here, I only consider the failed
> case CONFIG_NF_CONNTRACK=m.
>
> Thanks,
> Tiezhu
>

2023-01-18 07:30:47

by Tiezhu Yang

[permalink] [raw]
Subject: Re: [PATCH bpf-next] selftests/bpf: Fix undeclared identifier build errors of test_bpf_nf.c



On 01/18/2023 02:29 AM, Yonghong Song wrote:
>
>
> On 1/17/23 1:52 AM, Tiezhu Yang wrote:
>>
>>
>> On 01/17/2023 02:48 PM, Yonghong Song wrote:
>>>
>>>
>>> On 1/16/23 5:54 AM, Alan Maguire wrote:
>>>> On 16/01/2023 12:30, Eduard Zingerman wrote:
>>>>> On Mon, 2023-01-16 at 12:55 +0800, Tiezhu Yang wrote:
>>>>>> $ make -C tools/testing/selftests/bpf/
>>>>>>
>>>>>> CLNG-BPF [test_maps] test_bpf_nf.bpf.o
>>>>>> progs/test_bpf_nf.c:160:42: error: use of undeclared identifier
>>>>>> 'NF_NAT_MANIP_SRC'
>>>>>> bpf_ct_set_nat_info(ct, &saddr, sport,
>>>>>> NF_NAT_MANIP_SRC);
>>>>>> ^
>>>>>> progs/test_bpf_nf.c:163:42: error: use of undeclared identifier
>>>>>> 'NF_NAT_MANIP_DST'
>>>>>> bpf_ct_set_nat_info(ct, &daddr, dport,
>>>>>> NF_NAT_MANIP_DST);
>>>>>> ^
>>>>>> 2 errors generated.
>>>>>>
>>>>>> Copy the definitions in include/net/netfilter/nf_nat.h to
>>>>>> test_bpf_nf.c
>>>>>> to fix the above build errors.
>>>>>>
>>>>>> Fixes: b06b45e82b59 ("selftests/bpf: add tests for
>>>>>> bpf_ct_set_nat_info kfunc")
>>>>>> Signed-off-by: Tiezhu Yang <[email protected]>
>>>>>> ---
>>>>>> tools/testing/selftests/bpf/progs/test_bpf_nf.c | 5 +++++
>>>>>> 1 file changed, 5 insertions(+)
>>>>>>
>>>>>> diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>>>> b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>>>> index 227e85e..114f961 100644
>>>>>> --- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>>>> +++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>>>>>> @@ -34,6 +34,11 @@ __be16 dport = 0;
>>>>>> int test_exist_lookup = -ENOENT;
>>>>>> u32 test_exist_lookup_mark = 0;
>>>>>> +enum nf_nat_manip_type {
>>>>>> + NF_NAT_MANIP_SRC,
>>>>>> + NF_NAT_MANIP_DST
>>>>>> +};
>>>>>> +
>>>>>
>>>>> This is confusing, when I build the kernel/tests I get the declaration
>>>>> the "enum nf_nat_manip_type" from the vmlinux.h (which is included
>>>>> from test_bpf_nf.c).
>>>>> Which means that this patch results in compilation error with my
>>>>> configuration.
>>>>> Is there a chance that your kernel is configured without some
>>>>> necessary netfilter
>>>>> configuration options? Have you tried this patch with BPF CI?
>>>>>
>>>>
>>>> Yep; I suspect if CONFIG_NF_NAT=m , the required definitions won't
>>>> make it
>>>> into vmlinux.h. The reference tools/testing/seftests/bpf/config has
>>>> CONFIG_NF_NAT=y so it is at least documented in the referenced config.
>>>>
>>>> I'd suggest going the route of
>>>>
>>>> commit aa67961f3243dfff26c47769f87b4d94b07ec71f
>>>> Author: Martin KaFai Lau <[email protected]>
>>>> Date: Tue Dec 6 11:35:54 2022 -0800
>>>>
>>>> selftests/bpf: Allow building bpf tests with
>>>> CONFIG_XFRM_INTERFACE=[m|n]
>>>> ...and adding/using local definitons like:
>>>>
>>>> enum nf_nat_manip_type_local {
>>>> NF_NAT_MANIP_SRC_LOCAL,
>>>> NF_NAT_MANIP_DST_LOCAL
>>>> };
>>>
>>> The above won't support core, and since preserve_access_index attribute
>>> does not support enum for now. We need to use bpf_core_enum_value to
>>> retrieve the proper value through CORE.
>>>
>>> could you try the following?
>>>
>>> enum nf_nat_manip_type___local {
>>> NF_NAT_MANIP_SRC___LOCAL,
>>> NF_NAT_MANIP_DST___LOCAL,
>>> };
>>
>> This is OK, it is similar with commit 1058b6a78db2 ("selftests/bpf: Do
>> not fail build if CONFIG_NF_CONNTRACK=m/n").
>>
>>>
>>> ...
>>> bpf_ct_set_nat_info(ct, &saddr, sport, bpf_core_enum_value(enum
>>> nf_nat_manip_type___local, NF_NAT_MANIP_SRC___LOCAL));
>>> ...
>>>
>>> bpf_ct_set_nat_info(ct, &daddr, dport, bpf_core_enum_value(enum
>>> nf_nat_manip_type___local, NF_NAT_MANIP_DST___LOCAL));
>>>
>>> whether it works or not? Could you also try if the
>>> enumerator sequence in enum nf_nat_manip_type___local changed?
>>>
>>>>
>>>> ...to avoid the name clash.
>>>>
>>>>
>>>> Alan
>>
>> I tested this on x86_64 fedora 36, using config-5.17.5-300.fc36.x86_64
>> to generate .config, CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=m, there are
>> no definitions of NF_NAT_MANIP_SRC and NF_NAT_MANIP_DST in vmlinux.h,
>> build test_bpf_nf.c failed.
>
> Thanks for trying. Yes, I tried in my environment and it failed because
> I didn't change the enum nf_nat_manip_type type for kfunc:
> int bpf_ct_set_nat_info(struct nf_conn *, union nf_inet_addr *,
> int port, enum nf_nat_manip_type) __ksym;
>
> But when I changed 'enum nf_nat_manip_type' to
> 'enum nf_nat_manip_type___local', kernel complains kfunc argument
> mismatch. The reason most likely is 'enum nf_nat_manip_type___local'
> is not converted to 'enum nf_nat_manip_type' by libbpf.
>
> This might be expected as preserve_access_index attribute only
> supports record (struct/union) type and libbpf might just do that.
> Could you double check whether this is the case or not?
>
> Maybe it is time to implement preserve_access_index support
> for enum type in clang now.
>
> But we need to resolve the issue, even temporarily for now.
> See below.
>
>>
>> $ grep -w CONFIG_NF_CONNTRACK /boot/config-5.17.5-300.fc36.x86_64
>> CONFIG_NF_CONNTRACK=m
>> $ grep -w CONFIG_NF_NAT /boot/config-5.17.5-300.fc36.x86_64
>> CONFIG_NF_NAT=m
>>
>> I tested with various configs, the definitions of NF_NAT_MANIP_SRC and
>> NF_NAT_MANIP_DST in vmlinux.h only depend on CONFIG_NF_CONNTRACK=y.
>>
>> (1) CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=m, no definitions
>> $ grep -w CONFIG_NF_CONNTRACK .config
>> CONFIG_NF_CONNTRACK=m
>> $ grep -w CONFIG_NF_NAT .config
>> CONFIG_NF_NAT=m
>> $ grep NF_NAT_MANIP_SRC
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> $ grep NF_NAT_MANIP_DST
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> $
>>
>> (2) CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=y, no definitions
>> This case is unable, because CONFIG_NF_NAT depends on
>> CONFIG_NF_CONNTRACK.
>>
>> (3) CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=n, no definitions
>> $ grep -w CONFIG_NF_CONNTRACK .config
>> CONFIG_NF_CONNTRACK=m
>> $ grep -w CONFIG_NF_NAT .config
>> # CONFIG_NF_NAT is not set
>> $ grep NF_NAT_MANIP_SRC
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> $ grep NF_NAT_MANIP_DST
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> $
>>
>> (4) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=m, have definitions
>> $ grep -w CONFIG_NF_CONNTRACK .config
>> CONFIG_NF_CONNTRACK=y
>> $ grep -w CONFIG_NF_NAT .config
>> CONFIG_NF_NAT=m
>> $ grep NF_NAT_MANIP_SRC
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> NF_NAT_MANIP_SRC = 0,
>> $ grep NF_NAT_MANIP_DST
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> NF_NAT_MANIP_DST = 1,
>>
>> (5) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=y, have definitions
>> $ grep -w CONFIG_NF_CONNTRACK .config
>> CONFIG_NF_CONNTRACK=y
>> $ grep -w CONFIG_NF_NAT .config
>> CONFIG_NF_NAT=y
>> $ grep NF_NAT_MANIP_SRC
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> NF_NAT_MANIP_SRC = 0,
>> $ grep NF_NAT_MANIP_DST
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> NF_NAT_MANIP_DST = 1,
>>
>> (6) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=n, have definitions
>> $ grep -w CONFIG_NF_CONNTRACK .config
>> CONFIG_NF_CONNTRACK=y
>> $ grep -w CONFIG_NF_NAT .config
>> # CONFIG_NF_NAT is not set
>> $ grep NF_NAT_MANIP_SRC
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> NF_NAT_MANIP_SRC = 0,
>> $ grep NF_NAT_MANIP_DST
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> NF_NAT_MANIP_DST = 1,
>>
>> (7) CONFIG_NF_CONNTRACK=n, CONFIG_NF_NAT=n, no definitions
>> $ grep -w CONFIG_NF_CONNTRACK .config
>> # CONFIG_NF_CONNTRACK is not set
>> $ grep -w CONFIG_NF_NAT .config
>> $ grep NF_NAT_MANIP_SRC
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> $ grep NF_NAT_MANIP_DST
>> tools/testing/selftests/bpf/tools/include/vmlinux.h
>> $
>>
>> (8) CONFIG_NF_CONNTRACK=n, CONFIG_NF_NAT=y, no definitions
>> This case is unable, because CONFIG_NF_NAT depends on
>> CONFIG_NF_CONNTRACK.
>>
>> Here is an alternative change to check whether CONFIG_NF_CONNTRACK
>> is m, enum nf_nat_manip_type___local is simple, which one is better?
>>
>> $ git diff tools/testing/selftests/bpf/
>> diff --git a/tools/testing/selftests/bpf/Makefile
>> b/tools/testing/selftests/bpf/Makefile
>> index 22533a18705e..f3cf02046c20 100644
>> --- a/tools/testing/selftests/bpf/Makefile
>> +++ b/tools/testing/selftests/bpf/Makefile
>> @@ -325,7 +325,7 @@ endif
>>
>> CLANG_SYS_INCLUDES = $(call
>> get_sys_includes,$(CLANG),$(CLANG_TARGET_ARCH))
>> BPF_CFLAGS = -g -Werror -D__TARGET_ARCH_$(SRCARCH)
>> $(MENDIAN) \
>> - -I$(INCLUDE_DIR) -I$(CURDIR) -I$(APIDIR) \
>> + -I$(INCLUDE_DIR) -I$(CURDIR) -I$(APIDIR) -I$(TOOLSINCDIR) \
>> -I$(abspath $(OUTPUT)/../usr/include)
>>
>> CLANG_CFLAGS = $(CLANG_SYS_INCLUDES) \
>> diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>> b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>> index 227e85e85dda..f2101807072f 100644
>> --- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>> +++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
>> @@ -2,6 +2,7 @@
>> #include <vmlinux.h>
>> #include <bpf/bpf_helpers.h>
>> #include <bpf/bpf_endian.h>
>> +#include <linux/kconfig.h>
>>
>> #define EAFNOSUPPORT 97
>> #define EPROTO 71
>> @@ -34,6 +35,13 @@ __be16 dport = 0;
>> int test_exist_lookup = -ENOENT;
>> u32 test_exist_lookup_mark = 0;
>>
>> +#if IS_MODULE(CONFIG_NF_CONNTRACK)
>> +enum nf_nat_manip_type {
>> + NF_NAT_MANIP_SRC,
>> + NF_NAT_MANIP_DST
>> +};
>> +#endif
>> +
>
> The above change does not work for me. The complication failed with
>
> CLNG-BPF [test_maps]
> btf__core_reloc_nesting___err_missing_container.bpf.o
> CLNG-BPF [test_maps] test_sysctl_loop2.bpf.o
> progs/test_bpf_nf.c:168:42: error: use of undeclared identifier
> 'NF_NAT_MANIP_SRC'
> bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
> ^
> progs/test_bpf_nf.c:171:42: error: use of undeclared identifier
> 'NF_NAT_MANIP_DST'
> bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
> ^
> 2 errors generated.
>
>
> Apparently, IS_MODULE(...) is recognized but it returns 0.
> I do have CONFIG_NF_CONNTRACK=m in my config.
> Note that I build the kernel with KBUILD_OUTPUT=<another dir>
> (make -j LLVM=1) so vmlinux is in a different place.
> While I build selftest
> with 'make -C tools/testing/selftests/bpf -j LLVM=1' which
> is in-tree.
>
>> struct nf_conn;
>>
>> struct bpf_ct_opts___local {
>>
>> Note that when unset CONFIG_NF_CONNTRACK, there are much more
>> build errors, I do not know whether it is necessary to fix it
>> and how to fix it properly. Here, I only consider the failed
>> case CONFIG_NF_CONNTRACK=m.
>>
>> Thanks,
>> Tiezhu
>>

I have the following test environment:

system: x86_64 fedora 36
kernel: the latest bpf-next
clang: version 14.0.5 (Fedora 14.0.5-1.fc36)
gcc: 12.2.1 20220819 (Red Hat 12.2.1-2)

With the following changes, there are no any build errors and
warnings if
(1) CONFIG_NF_CONNTRACK=m, CONFIG_NF_NAT=m
(2) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=m
(3) CONFIG_NF_CONNTRACK=y, CONFIG_NF_NAT=y

$ git diff
diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
index 227e85e85dda..9fc603c9d673 100644
--- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
+++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
@@ -34,6 +34,11 @@ __be16 dport = 0;
int test_exist_lookup = -ENOENT;
u32 test_exist_lookup_mark = 0;

+enum nf_nat_manip_type___local {
+ NF_NAT_MANIP_SRC___local,
+ NF_NAT_MANIP_DST___local
+};
+
struct nf_conn;

struct bpf_ct_opts___local {
@@ -58,7 +63,7 @@ int bpf_ct_change_timeout(struct nf_conn *, u32) __ksym;
int bpf_ct_set_status(struct nf_conn *, u32) __ksym;
int bpf_ct_change_status(struct nf_conn *, u32) __ksym;
int bpf_ct_set_nat_info(struct nf_conn *, union nf_inet_addr *,
- int port, enum nf_nat_manip_type) __ksym;
+ int port, enum nf_nat_manip_type___local) __ksym;

static __always_inline void
nf_ct_test(struct nf_conn *(*lookup_fn)(void *, struct bpf_sock_tuple
*, u32,
@@ -157,10 +162,10 @@ nf_ct_test(struct nf_conn *(*lookup_fn)(void *,
struct bpf_sock_tuple *, u32,

/* snat */
saddr.ip = bpf_get_prandom_u32();
- bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
+ bpf_ct_set_nat_info(ct, &saddr, sport,
NF_NAT_MANIP_SRC___local);
/* dnat */
daddr.ip = bpf_get_prandom_u32();
- bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
+ bpf_ct_set_nat_info(ct, &daddr, dport,
NF_NAT_MANIP_DST___local);

ct_ins = bpf_ct_insert_entry(ct);
if (ct_ins) {

I will send it as a normal patch for your review, let us see what is
the status of BPF CI.

Thanks,
Tiezhu