diff mbox series

[bpf,v3,2/2] selftests/bpf: fix endianness issues in test_sysctl

Message ID 20190828132214.68828-3-iii@linux.ibm.com
State Changes Requested
Delegated to: BPF Maintainers
Headers show
Series selftests/bpf: fix endianness issues in test_sysctl | expand

Commit Message

Ilya Leoshkevich Aug. 28, 2019, 1:22 p.m. UTC 
A lot of test_sysctl sub-tests fail due to handling strings as a bunch
of immediate values in a little-endian-specific manner.

Fix by wrapping all immediates in bpf_ntohl and the new bpf_be64_to_cpu.

Also, sometimes tests fail because sysctl() unexpectedly succeeds with
an inappropriate "Unexpected failure" message and a random errno. Zero
out errno before calling sysctl() and replace the message with
"Unexpected success".

Fixes: 1f5fa9ab6e2e ("selftests/bpf: Test BPF_CGROUP_SYSCTL")
Fixes: 9a1027e52535 ("selftests/bpf: Test file_pos field in bpf_sysctl ctx")
Fixes: 6041c67f28d8 ("selftests/bpf: Test bpf_sysctl_get_name helper")
Fixes: 11ff34f74e32 ("selftests/bpf: Test sysctl_get_current_value helper")
Fixes: 786047dd08de ("selftests/bpf: Test bpf_sysctl_{get,set}_new_value helpers")
Fixes: 8549ddc832d6 ("selftests/bpf: Test bpf_strtol and bpf_strtoul helpers")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 tools/testing/selftests/bpf/test_sysctl.c | 130 ++++++++++++++--------
 1 file changed, 85 insertions(+), 45 deletions(-)

Comments

Song Liu Aug. 29, 2019, 9:53 p.m. UTC | #1 
On Wed, Aug 28, 2019 at 6:22 AM Ilya Leoshkevich <iii@linux.ibm.com> wrote:
>
> A lot of test_sysctl sub-tests fail due to handling strings as a bunch
> of immediate values in a little-endian-specific manner.
>
> Fix by wrapping all immediates in bpf_ntohl and the new bpf_be64_to_cpu.
>
> Also, sometimes tests fail because sysctl() unexpectedly succeeds with
> an inappropriate "Unexpected failure" message and a random errno. Zero
> out errno before calling sysctl() and replace the message with
> "Unexpected success".
>
> Fixes: 1f5fa9ab6e2e ("selftests/bpf: Test BPF_CGROUP_SYSCTL")
> Fixes: 9a1027e52535 ("selftests/bpf: Test file_pos field in bpf_sysctl ctx")
> Fixes: 6041c67f28d8 ("selftests/bpf: Test bpf_sysctl_get_name helper")
> Fixes: 11ff34f74e32 ("selftests/bpf: Test sysctl_get_current_value helper")
> Fixes: 786047dd08de ("selftests/bpf: Test bpf_sysctl_{get,set}_new_value helpers")
> Fixes: 8549ddc832d6 ("selftests/bpf: Test bpf_strtol and bpf_strtoul helpers")
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>  tools/testing/selftests/bpf/test_sysctl.c | 130 ++++++++++++++--------
>  1 file changed, 85 insertions(+), 45 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/test_sysctl.c b/tools/testing/selftests/bpf/test_sysctl.c
> index a3bebd7c68dd..b8c6e31645cb 100644
> --- a/tools/testing/selftests/bpf/test_sysctl.c
> +++ b/tools/testing/selftests/bpf/test_sysctl.c
> @@ -13,6 +13,7 @@
>  #include <bpf/bpf.h>
>  #include <bpf/libbpf.h>
>
> +#include "bpf_endian.h"
>  #include "bpf_rlimit.h"
>  #include "bpf_util.h"
>  #include "cgroup_helpers.h"
> @@ -100,7 +101,7 @@ static struct sysctl_test tests[] = {
>                 .descr = "ctx:write sysctl:write read ok",
>                 .insns = {
>                         /* If (write) */
> -                       BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_1,
> +                       BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_1,

I didn't find explanation for this change in the commit log. Is this a typo, or
a real fix?

>                                     offsetof(struct bpf_sysctl, write)),
>                         BPF_JMP_IMM(BPF_JNE, BPF_REG_7, 1, 2),
>
> @@ -214,7 +215,8 @@ static struct sysctl_test tests[] = {
>                         /* if (ret == expected && */
>                         BPF_JMP_IMM(BPF_JNE, BPF_REG_0, sizeof("tcp_mem") - 1, 6),
>                         /*     buf == "tcp_mem\0") */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x006d656d5f706374ULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x7463705f6d656d00ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
>
> @@ -255,7 +257,8 @@ static struct sysctl_test tests[] = {
>                         BPF_JMP_IMM(BPF_JNE, BPF_REG_0, -E2BIG, 6),
>
>                         /*     buf[0:7] == "tcp_me\0") */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x00656d5f706374ULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x7463705f6d650000ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
>
> @@ -298,12 +301,14 @@ static struct sysctl_test tests[] = {
>                         BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 16, 14),
>
>                         /*     buf[0:8] == "net/ipv4" && */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x347670692f74656eULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x6e65742f69707634ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 10),
>
>                         /*     buf[8:16] == "/tcp_mem" && */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x6d656d5f7063742fULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x2f7463705f6d656dULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 8),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 6),
>
> @@ -350,12 +355,14 @@ static struct sysctl_test tests[] = {
>                         BPF_JMP_IMM(BPF_JNE, BPF_REG_0, -E2BIG, 10),
>
>                         /*     buf[0:8] == "net/ipv4" && */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x347670692f74656eULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x6e65742f69707634ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 6),
>
>                         /*     buf[8:16] == "/tcp_me\0") */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x00656d5f7063742fULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x2f7463705f6d6500ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 8),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
>
> @@ -396,7 +403,8 @@ static struct sysctl_test tests[] = {
>                         BPF_JMP_IMM(BPF_JNE, BPF_REG_0, -E2BIG, 6),
>
>                         /*     buf[0:8] == "net/ip\0") */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x000070692f74656eULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x6e65742f69700000ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
>
> @@ -431,7 +439,8 @@ static struct sysctl_test tests[] = {
>                         BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 6, 6),
>
>                         /*     buf[0:6] == "Linux\n\0") */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x000a78756e694cULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x4c696e75780a0000ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
>
> @@ -469,7 +478,8 @@ static struct sysctl_test tests[] = {
>                         BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 6, 6),
>
>                         /*     buf[0:6] == "Linux\n\0") */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x000a78756e694cULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x4c696e75780a0000ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
>
> @@ -507,7 +517,8 @@ static struct sysctl_test tests[] = {
>                         BPF_JMP_IMM(BPF_JNE, BPF_REG_0, -E2BIG, 6),
>
>                         /*     buf[0:6] == "Linux\0") */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x000078756e694cULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x4c696e7578000000ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
>
> @@ -650,7 +661,8 @@ static struct sysctl_test tests[] = {
>
>                         /*     buf[0:4] == "606\0") */
>                         BPF_LDX_MEM(BPF_W, BPF_REG_9, BPF_REG_7, 0),
> -                       BPF_JMP_IMM(BPF_JNE, BPF_REG_9, 0x00363036, 2),
> +                       BPF_JMP_IMM(BPF_JNE, BPF_REG_9,
> +                                   bpf_ntohl(0x36303600), 2),
>
>                         /* return DENY; */
>                         BPF_MOV64_IMM(BPF_REG_0, 0),
> @@ -685,17 +697,20 @@ static struct sysctl_test tests[] = {
>                         BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 23, 14),
>
>                         /*     buf[0:8] == "3000000 " && */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x2030303030303033ULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x3330303030303020ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 10),
>
>                         /*     buf[8:16] == "4000000 " && */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x2030303030303034ULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x3430303030303020ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 8),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 6),
>
>                         /*     buf[16:24] == "6000000\0") */
> -                       BPF_LD_IMM64(BPF_REG_8, 0x0030303030303036ULL),
> +                       BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
> +                               0x3630303030303000ULL)),
>                         BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 16),
>                         BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
>
> @@ -735,7 +750,8 @@ static struct sysctl_test tests[] = {
>
>                         /*     buf[0:3] == "60\0") */
>                         BPF_LDX_MEM(BPF_W, BPF_REG_9, BPF_REG_7, 0),
> -                       BPF_JMP_IMM(BPF_JNE, BPF_REG_9, 0x003036, 2),
> +                       BPF_JMP_IMM(BPF_JNE, BPF_REG_9,
> +                                   bpf_ntohl(0x36300000), 2),
>
>                         /* return DENY; */
>                         BPF_MOV64_IMM(BPF_REG_0, 0),
> @@ -757,7 +773,8 @@ static struct sysctl_test tests[] = {
>                         /* sysctl_set_new_value arg2 (buf) */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
> -                       BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
> +                       BPF_MOV64_IMM(BPF_REG_0,
> +                                     bpf_ntohl(0x36303000)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
>
>                         BPF_MOV64_REG(BPF_REG_2, BPF_REG_7),
> @@ -791,7 +808,7 @@ static struct sysctl_test tests[] = {
>                         /* sysctl_set_new_value arg2 (buf) */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
> -                       BPF_MOV64_IMM(BPF_REG_0, FIXUP_SYSCTL_VALUE),
> +                       BPF_LD_IMM64(BPF_REG_0, FIXUP_SYSCTL_VALUE),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
>
>                         BPF_MOV64_REG(BPF_REG_2, BPF_REG_7),
> @@ -825,8 +842,9 @@ static struct sysctl_test tests[] = {
>                         /* arg1 (buf) */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
> -                       BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
> -                       BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
> +                       BPF_MOV64_IMM(BPF_REG_0,
> +                                     bpf_ntohl(0x36303000)),
> +                       BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
>
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
>
> @@ -869,7 +887,8 @@ static struct sysctl_test tests[] = {
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
>                         /* "600 602\0" */
> -                       BPF_LD_IMM64(BPF_REG_0, 0x0032303620303036ULL),
> +                       BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
> +                               0x3630302036303200ULL)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
>
> @@ -937,7 +956,8 @@ static struct sysctl_test tests[] = {
>                         /* arg1 (buf) */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
> -                       BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
> +                       BPF_MOV64_IMM(BPF_REG_0,
> +                                     bpf_ntohl(0x36303000)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
>
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
> @@ -969,8 +989,9 @@ static struct sysctl_test tests[] = {
>                         /* arg1 (buf) */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
> -                       BPF_MOV64_IMM(BPF_REG_0, 0x00373730),
> -                       BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
> +                       BPF_MOV64_IMM(BPF_REG_0,
> +                                     bpf_ntohl(0x30373700)),
> +                       BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
>
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
>
> @@ -1012,7 +1033,8 @@ static struct sysctl_test tests[] = {
>                         /* arg1 (buf) */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
> -                       BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
> +                       BPF_MOV64_IMM(BPF_REG_0,
> +                                     bpf_ntohl(0x36303000)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
>
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
> @@ -1052,7 +1074,8 @@ static struct sysctl_test tests[] = {
>                         /* arg1 (buf) */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
> -                       BPF_MOV64_IMM(BPF_REG_0, 0x090a0c0d),
> +                       BPF_MOV64_IMM(BPF_REG_0,
> +                                     bpf_ntohl(0x0d0c0a09)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
>
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
> @@ -1092,7 +1115,9 @@ static struct sysctl_test tests[] = {
>                         /* arg1 (buf) */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
> -                       BPF_MOV64_IMM(BPF_REG_0, 0x00362d0a), /* " -6\0" */
> +                       /* " -6\0" */
> +                       BPF_MOV64_IMM(BPF_REG_0,
> +                                     bpf_ntohl(0x0a2d3600)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
>
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
> @@ -1132,8 +1157,10 @@ static struct sysctl_test tests[] = {
>                         /* arg1 (buf) */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
> -                       BPF_MOV64_IMM(BPF_REG_0, 0x00362d0a), /* " -6\0" */
> -                       BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
> +                       /* " -6\0" */
> +                       BPF_MOV64_IMM(BPF_REG_0,
> +                                     bpf_ntohl(0x0a2d3600)),
> +                       BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
>
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
>
> @@ -1175,8 +1202,10 @@ static struct sysctl_test tests[] = {
>                         /* arg1 (buf) */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
> -                       BPF_MOV64_IMM(BPF_REG_0, 0x65667830), /* "0xfe" */
> -                       BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
> +                       /* "0xfe" */
> +                       BPF_MOV64_IMM(BPF_REG_0,
> +                                     bpf_ntohl(0x30786665)),
> +                       BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
>
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
>
> @@ -1218,11 +1247,14 @@ static struct sysctl_test tests[] = {
>                         /* arg1 (buf) 9223372036854775807 */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -24),
> -                       BPF_LD_IMM64(BPF_REG_0, 0x3032373333323239ULL),
> +                       BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
> +                               0x3932323333373230ULL)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
> -                       BPF_LD_IMM64(BPF_REG_0, 0x3537373435383633ULL),
> +                       BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
> +                               0x3336383534373735ULL)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 8),
> -                       BPF_LD_IMM64(BPF_REG_0, 0x0000000000373038ULL),
> +                       BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
> +                               0x3830370000000000ULL)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 16),
>
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
> @@ -1266,11 +1298,14 @@ static struct sysctl_test tests[] = {
>                         /* arg1 (buf) 9223372036854775808 */
>                         BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
>                         BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -24),
> -                       BPF_LD_IMM64(BPF_REG_0, 0x3032373333323239ULL),
> +                       BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
> +                               0x3932323333373230ULL)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
> -                       BPF_LD_IMM64(BPF_REG_0, 0x3537373435383633ULL),
> +                       BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
> +                               0x3336383534373735ULL)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 8),
> -                       BPF_LD_IMM64(BPF_REG_0, 0x0000000000383038ULL),
> +                       BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
> +                               0x3830380000000000ULL)),
>                         BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 16),
>
>                         BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
> @@ -1344,20 +1379,24 @@ static size_t probe_prog_length(const struct bpf_insn *fp)
>  static int fixup_sysctl_value(const char *buf, size_t buf_len,
>                               struct bpf_insn *prog, size_t insn_num)
>  {
> -       uint32_t value_num = 0;
> +       union {
> +               uint8_t raw[sizeof(uint64_t)];
> +               uint64_t num;
> +       } value = {};

This change doesn't match the description in the changelog.

>         uint8_t c, i;
>
> -       if (buf_len > sizeof(value_num)) {
> +       if (buf_len > sizeof(value)) {
>                 log_err("Value is too big (%zd) to use in fixup", buf_len);
>                 return -1;
>         }
> -
> -       for (i = 0; i < buf_len; ++i) {
> -               c = buf[i];
> -               value_num |= (c << i * 8);
> +       if (prog[insn_num].code != (BPF_LD | BPF_DW | BPF_IMM)) {
> +               log_err("Can fixup only BPF_LD_IMM64 insns");
> +               return -1;
>         }
>
> -       prog[insn_num].imm = value_num;
> +       memcpy(value.raw, buf, buf_len);
> +       prog[insn_num].imm = (uint32_t)value.num;
> +       prog[insn_num + 1].imm = (uint32_t)(value.num >> 32);
>
>         return 0;
>  }
> @@ -1499,6 +1538,7 @@ static int run_test_case(int cgfd, struct sysctl_test *test)
>                         goto err;
>         }
>
> +       errno = 0;
>         if (access_sysctl(sysctl_path, test) == -1) {
>                 if (test->result == OP_EPERM && errno == EPERM)
>                         goto out;
> @@ -1507,7 +1547,7 @@ static int run_test_case(int cgfd, struct sysctl_test *test)
>         }
>
>         if (test->result != SUCCESS) {
> -               log_err("Unexpected failure");
> +               log_err("Unexpected success");
>                 goto err;
>         }
>
> --
> 2.21.0
>
Ilya Leoshkevich Aug. 30, 2019, 10:22 a.m. UTC | #2 
> Am 29.08.2019 um 23:53 schrieb Song Liu <liu.song.a23@gmail.com>:
> 
> On Wed, Aug 28, 2019 at 6:22 AM Ilya Leoshkevich <iii@linux.ibm.com> wrote:
>> 
>> A lot of test_sysctl sub-tests fail due to handling strings as a bunch
>> of immediate values in a little-endian-specific manner.
>> 
>> Fix by wrapping all immediates in bpf_ntohl and the new bpf_be64_to_cpu.
>> 
>> Also, sometimes tests fail because sysctl() unexpectedly succeeds with
>> an inappropriate "Unexpected failure" message and a random errno. Zero
>> out errno before calling sysctl() and replace the message with
>> "Unexpected success".

...

>> @@ -13,6 +13,7 @@
>> #include <bpf/bpf.h>
>> #include <bpf/libbpf.h>
>> 
>> +#include "bpf_endian.h"
>> #include "bpf_rlimit.h"
>> #include "bpf_util.h"
>> #include "cgroup_helpers.h"
>> @@ -100,7 +101,7 @@ static struct sysctl_test tests[] = {
>>                .descr = "ctx:write sysctl:write read ok",
>>                .insns = {
>>                        /* If (write) */
>> -                       BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_1,
>> +                       BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_1,
> 
> I didn't find explanation for this change in the commit log. Is this a typo, or
> a real fix?

This is a real fix, but I forgot to explain it.  We read the first byte of an
int assuming it's the least-significant one, which is not the case on BE arches.
Two fixes are possible: use a different offset on BE arches or just read the
whole int.  Since we are not testing narrow accesses here (there is e.g.
"ctx:file_pos sysctl:read read ok narrow" for that), I went with the simplest
solution.

...

>> @@ -1344,20 +1379,24 @@ static size_t probe_prog_length(const struct bpf_insn *fp)
>> static int fixup_sysctl_value(const char *buf, size_t buf_len,
>>                              struct bpf_insn *prog, size_t insn_num)
>> {
>> -       uint32_t value_num = 0;
>> +       union {
>> +               uint8_t raw[sizeof(uint64_t)];
>> +               uint64_t num;
>> +       } value = {};
> 
> This change doesn't match the description in the changelog.

This one I also forgot to explain - writing an immediate into things like
BPF_LD_IMM64(BPF_REG_0, FIXUP_SYSCTL_VALUE) should be endianness-aware.  We can
also do bpf_be64_to_cpu or similar here, but a better trick (suggested by
Yonghong) is to simply memcpy the raw user-provided value, since testcase
endianness and bpf program endianness match.


Let me send a v4 with an improved commit message.
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/test_sysctl.c b/tools/testing/selftests/bpf/test_sysctl.c
index a3bebd7c68dd..b8c6e31645cb 100644
--- a/tools/testing/selftests/bpf/test_sysctl.c
+++ b/tools/testing/selftests/bpf/test_sysctl.c
@@ -13,6 +13,7 @@ 
 #include <bpf/bpf.h>
 #include <bpf/libbpf.h>
 
+#include "bpf_endian.h"
 #include "bpf_rlimit.h"
 #include "bpf_util.h"
 #include "cgroup_helpers.h"
@@ -100,7 +101,7 @@  static struct sysctl_test tests[] = {
 		.descr = "ctx:write sysctl:write read ok",
 		.insns = {
 			/* If (write) */
-			BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_1,
+			BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_1,
 				    offsetof(struct bpf_sysctl, write)),
 			BPF_JMP_IMM(BPF_JNE, BPF_REG_7, 1, 2),
 
@@ -214,7 +215,8 @@  static struct sysctl_test tests[] = {
 			/* if (ret == expected && */
 			BPF_JMP_IMM(BPF_JNE, BPF_REG_0, sizeof("tcp_mem") - 1, 6),
 			/*     buf == "tcp_mem\0") */
-			BPF_LD_IMM64(BPF_REG_8, 0x006d656d5f706374ULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x7463705f6d656d00ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
 
@@ -255,7 +257,8 @@  static struct sysctl_test tests[] = {
 			BPF_JMP_IMM(BPF_JNE, BPF_REG_0, -E2BIG, 6),
 
 			/*     buf[0:7] == "tcp_me\0") */
-			BPF_LD_IMM64(BPF_REG_8, 0x00656d5f706374ULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x7463705f6d650000ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
 
@@ -298,12 +301,14 @@  static struct sysctl_test tests[] = {
 			BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 16, 14),
 
 			/*     buf[0:8] == "net/ipv4" && */
-			BPF_LD_IMM64(BPF_REG_8, 0x347670692f74656eULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x6e65742f69707634ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 10),
 
 			/*     buf[8:16] == "/tcp_mem" && */
-			BPF_LD_IMM64(BPF_REG_8, 0x6d656d5f7063742fULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x2f7463705f6d656dULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 8),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 6),
 
@@ -350,12 +355,14 @@  static struct sysctl_test tests[] = {
 			BPF_JMP_IMM(BPF_JNE, BPF_REG_0, -E2BIG, 10),
 
 			/*     buf[0:8] == "net/ipv4" && */
-			BPF_LD_IMM64(BPF_REG_8, 0x347670692f74656eULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x6e65742f69707634ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 6),
 
 			/*     buf[8:16] == "/tcp_me\0") */
-			BPF_LD_IMM64(BPF_REG_8, 0x00656d5f7063742fULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x2f7463705f6d6500ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 8),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
 
@@ -396,7 +403,8 @@  static struct sysctl_test tests[] = {
 			BPF_JMP_IMM(BPF_JNE, BPF_REG_0, -E2BIG, 6),
 
 			/*     buf[0:8] == "net/ip\0") */
-			BPF_LD_IMM64(BPF_REG_8, 0x000070692f74656eULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x6e65742f69700000ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
 
@@ -431,7 +439,8 @@  static struct sysctl_test tests[] = {
 			BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 6, 6),
 
 			/*     buf[0:6] == "Linux\n\0") */
-			BPF_LD_IMM64(BPF_REG_8, 0x000a78756e694cULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x4c696e75780a0000ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
 
@@ -469,7 +478,8 @@  static struct sysctl_test tests[] = {
 			BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 6, 6),
 
 			/*     buf[0:6] == "Linux\n\0") */
-			BPF_LD_IMM64(BPF_REG_8, 0x000a78756e694cULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x4c696e75780a0000ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
 
@@ -507,7 +517,8 @@  static struct sysctl_test tests[] = {
 			BPF_JMP_IMM(BPF_JNE, BPF_REG_0, -E2BIG, 6),
 
 			/*     buf[0:6] == "Linux\0") */
-			BPF_LD_IMM64(BPF_REG_8, 0x000078756e694cULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x4c696e7578000000ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
 
@@ -650,7 +661,8 @@  static struct sysctl_test tests[] = {
 
 			/*     buf[0:4] == "606\0") */
 			BPF_LDX_MEM(BPF_W, BPF_REG_9, BPF_REG_7, 0),
-			BPF_JMP_IMM(BPF_JNE, BPF_REG_9, 0x00363036, 2),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_9,
+				    bpf_ntohl(0x36303600), 2),
 
 			/* return DENY; */
 			BPF_MOV64_IMM(BPF_REG_0, 0),
@@ -685,17 +697,20 @@  static struct sysctl_test tests[] = {
 			BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 23, 14),
 
 			/*     buf[0:8] == "3000000 " && */
-			BPF_LD_IMM64(BPF_REG_8, 0x2030303030303033ULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x3330303030303020ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 10),
 
 			/*     buf[8:16] == "4000000 " && */
-			BPF_LD_IMM64(BPF_REG_8, 0x2030303030303034ULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x3430303030303020ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 8),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 6),
 
 			/*     buf[16:24] == "6000000\0") */
-			BPF_LD_IMM64(BPF_REG_8, 0x0030303030303036ULL),
+			BPF_LD_IMM64(BPF_REG_8, bpf_be64_to_cpu(
+				0x3630303030303000ULL)),
 			BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 16),
 			BPF_JMP_REG(BPF_JNE, BPF_REG_8, BPF_REG_9, 2),
 
@@ -735,7 +750,8 @@  static struct sysctl_test tests[] = {
 
 			/*     buf[0:3] == "60\0") */
 			BPF_LDX_MEM(BPF_W, BPF_REG_9, BPF_REG_7, 0),
-			BPF_JMP_IMM(BPF_JNE, BPF_REG_9, 0x003036, 2),
+			BPF_JMP_IMM(BPF_JNE, BPF_REG_9,
+				    bpf_ntohl(0x36300000), 2),
 
 			/* return DENY; */
 			BPF_MOV64_IMM(BPF_REG_0, 0),
@@ -757,7 +773,8 @@  static struct sysctl_test tests[] = {
 			/* sysctl_set_new_value arg2 (buf) */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
-			BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
+			BPF_MOV64_IMM(BPF_REG_0,
+				      bpf_ntohl(0x36303000)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
 
 			BPF_MOV64_REG(BPF_REG_2, BPF_REG_7),
@@ -791,7 +808,7 @@  static struct sysctl_test tests[] = {
 			/* sysctl_set_new_value arg2 (buf) */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
-			BPF_MOV64_IMM(BPF_REG_0, FIXUP_SYSCTL_VALUE),
+			BPF_LD_IMM64(BPF_REG_0, FIXUP_SYSCTL_VALUE),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
 
 			BPF_MOV64_REG(BPF_REG_2, BPF_REG_7),
@@ -825,8 +842,9 @@  static struct sysctl_test tests[] = {
 			/* arg1 (buf) */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
-			BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
-			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
+			BPF_MOV64_IMM(BPF_REG_0,
+				      bpf_ntohl(0x36303000)),
+			BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
 
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
 
@@ -869,7 +887,8 @@  static struct sysctl_test tests[] = {
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
 			/* "600 602\0" */
-			BPF_LD_IMM64(BPF_REG_0, 0x0032303620303036ULL),
+			BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
+				0x3630302036303200ULL)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
 
@@ -937,7 +956,8 @@  static struct sysctl_test tests[] = {
 			/* arg1 (buf) */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
-			BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
+			BPF_MOV64_IMM(BPF_REG_0,
+				      bpf_ntohl(0x36303000)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
 
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
@@ -969,8 +989,9 @@  static struct sysctl_test tests[] = {
 			/* arg1 (buf) */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
-			BPF_MOV64_IMM(BPF_REG_0, 0x00373730),
-			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
+			BPF_MOV64_IMM(BPF_REG_0,
+				      bpf_ntohl(0x30373700)),
+			BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
 
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
 
@@ -1012,7 +1033,8 @@  static struct sysctl_test tests[] = {
 			/* arg1 (buf) */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
-			BPF_MOV64_IMM(BPF_REG_0, 0x00303036),
+			BPF_MOV64_IMM(BPF_REG_0,
+				      bpf_ntohl(0x36303000)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
 
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
@@ -1052,7 +1074,8 @@  static struct sysctl_test tests[] = {
 			/* arg1 (buf) */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
-			BPF_MOV64_IMM(BPF_REG_0, 0x090a0c0d),
+			BPF_MOV64_IMM(BPF_REG_0,
+				      bpf_ntohl(0x0d0c0a09)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
 
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
@@ -1092,7 +1115,9 @@  static struct sysctl_test tests[] = {
 			/* arg1 (buf) */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
-			BPF_MOV64_IMM(BPF_REG_0, 0x00362d0a), /* " -6\0" */
+			/* " -6\0" */
+			BPF_MOV64_IMM(BPF_REG_0,
+				      bpf_ntohl(0x0a2d3600)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
 
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
@@ -1132,8 +1157,10 @@  static struct sysctl_test tests[] = {
 			/* arg1 (buf) */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
-			BPF_MOV64_IMM(BPF_REG_0, 0x00362d0a), /* " -6\0" */
-			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
+			/* " -6\0" */
+			BPF_MOV64_IMM(BPF_REG_0,
+				      bpf_ntohl(0x0a2d3600)),
+			BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
 
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
 
@@ -1175,8 +1202,10 @@  static struct sysctl_test tests[] = {
 			/* arg1 (buf) */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
-			BPF_MOV64_IMM(BPF_REG_0, 0x65667830), /* "0xfe" */
-			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
+			/* "0xfe" */
+			BPF_MOV64_IMM(BPF_REG_0,
+				      bpf_ntohl(0x30786665)),
+			BPF_STX_MEM(BPF_W, BPF_REG_7, BPF_REG_0, 0),
 
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
 
@@ -1218,11 +1247,14 @@  static struct sysctl_test tests[] = {
 			/* arg1 (buf) 9223372036854775807 */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -24),
-			BPF_LD_IMM64(BPF_REG_0, 0x3032373333323239ULL),
+			BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
+				0x3932323333373230ULL)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
-			BPF_LD_IMM64(BPF_REG_0, 0x3537373435383633ULL),
+			BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
+				0x3336383534373735ULL)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 8),
-			BPF_LD_IMM64(BPF_REG_0, 0x0000000000373038ULL),
+			BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
+				0x3830370000000000ULL)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 16),
 
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
@@ -1266,11 +1298,14 @@  static struct sysctl_test tests[] = {
 			/* arg1 (buf) 9223372036854775808 */
 			BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -24),
-			BPF_LD_IMM64(BPF_REG_0, 0x3032373333323239ULL),
+			BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
+				0x3932323333373230ULL)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
-			BPF_LD_IMM64(BPF_REG_0, 0x3537373435383633ULL),
+			BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
+				0x3336383534373735ULL)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 8),
-			BPF_LD_IMM64(BPF_REG_0, 0x0000000000383038ULL),
+			BPF_LD_IMM64(BPF_REG_0, bpf_be64_to_cpu(
+				0x3830380000000000ULL)),
 			BPF_STX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 16),
 
 			BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
@@ -1344,20 +1379,24 @@  static size_t probe_prog_length(const struct bpf_insn *fp)
 static int fixup_sysctl_value(const char *buf, size_t buf_len,
 			      struct bpf_insn *prog, size_t insn_num)
 {
-	uint32_t value_num = 0;
+	union {
+		uint8_t raw[sizeof(uint64_t)];
+		uint64_t num;
+	} value = {};
 	uint8_t c, i;
 
-	if (buf_len > sizeof(value_num)) {
+	if (buf_len > sizeof(value)) {
 		log_err("Value is too big (%zd) to use in fixup", buf_len);
 		return -1;
 	}
-
-	for (i = 0; i < buf_len; ++i) {
-		c = buf[i];
-		value_num |= (c << i * 8);
+	if (prog[insn_num].code != (BPF_LD | BPF_DW | BPF_IMM)) {
+		log_err("Can fixup only BPF_LD_IMM64 insns");
+		return -1;
 	}
 
-	prog[insn_num].imm = value_num;
+	memcpy(value.raw, buf, buf_len);
+	prog[insn_num].imm = (uint32_t)value.num;
+	prog[insn_num + 1].imm = (uint32_t)(value.num >> 32);
 
 	return 0;
 }
@@ -1499,6 +1538,7 @@  static int run_test_case(int cgfd, struct sysctl_test *test)
 			goto err;
 	}
 
+	errno = 0;
 	if (access_sysctl(sysctl_path, test) == -1) {
 		if (test->result == OP_EPERM && errno == EPERM)
 			goto out;
@@ -1507,7 +1547,7 @@  static int run_test_case(int cgfd, struct sysctl_test *test)
 	}
 
 	if (test->result != SUCCESS) {
-		log_err("Unexpected failure");
+		log_err("Unexpected success");
 		goto err;
 	}