selftests/bpf: fix endianness issues in test_sysctl

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.

fixup_sysctl_value() dynamically writes an immediate, and thus should be
endianness-aware.  Implement this by simply memcpy()ing the raw
user-provided value, since testcase endianness and bpf program
endianness match.

Fixes: 1f5fa9ab6e ("selftests/bpf: Test BPF_CGROUP_SYSCTL")
Fixes: 9a1027e525 ("selftests/bpf: Test file_pos field in bpf_sysctl ctx")
Fixes: 6041c67f28 ("selftests/bpf: Test bpf_sysctl_get_name helper")
Fixes: 11ff34f74e ("selftests/bpf: Test sysctl_get_current_value helper")
Fixes: 786047dd08 ("selftests/bpf: Test bpf_sysctl_{get,set}_new_value helpers")
Fixes: 8549ddc832 ("selftests/bpf: Test bpf_strtol and bpf_strtoul helpers")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Ilya Leoshkevich 2019-08-30 13:07:32 +02:00 committed by Daniel Borkmann
parent 416c572821
commit 3ec2a0ed3f
1 changed files with 82 additions and 43 deletions

View File

@ -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"
@ -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;
}