* [PATCH bpf] selftests/bpf: fix endianness issues in test_sysctl
@ 2019-08-15 12:25 Ilya Leoshkevich
2019-08-15 20:35 ` Andrey Ignatov
2019-08-16 0:05 ` Yonghong Song
0 siblings, 2 replies; 6+ messages in thread
From: Ilya Leoshkevich @ 2019-08-15 12:25 UTC (permalink / raw)
To: Daniel Borkmann, Alexei Starovoitov
Cc: bpf, Heiko Carstens, Vasily Gorbik, Ilya Leoshkevich
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_constant_ntohl,
__bpf_constant_be64_to_cpu and __bpf_le64_to_cpu.
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/bpf_endian.h | 4 +
tools/testing/selftests/bpf/test_sysctl.c | 122 +++++++++++++++-------
2 files changed, 86 insertions(+), 40 deletions(-)
diff --git a/tools/testing/selftests/bpf/bpf_endian.h b/tools/testing/selftests/bpf/bpf_endian.h
index 05f036df8a4c..94175c993806 100644
--- a/tools/testing/selftests/bpf/bpf_endian.h
+++ b/tools/testing/selftests/bpf/bpf_endian.h
@@ -29,6 +29,8 @@
# define __bpf_htonl(x) __builtin_bswap32(x)
# define __bpf_constant_ntohl(x) ___constant_swab32(x)
# define __bpf_constant_htonl(x) ___constant_swab32(x)
+# define __bpf_le64_to_cpu(x) (x)
+# define __bpf_constant_be64_to_cpu(x) ___constant_swab64(x)
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
# define __bpf_ntohs(x) (x)
# define __bpf_htons(x) (x)
@@ -38,6 +40,8 @@
# define __bpf_htonl(x) (x)
# define __bpf_constant_ntohl(x) (x)
# define __bpf_constant_htonl(x) (x)
+# define __bpf_le64_to_cpu(x) __swab64(x)
+# define __bpf_constant_be64_to_cpu(x) (x)
#else
# error "Fix your compiler's __BYTE_ORDER__?!"
#endif
diff --git a/tools/testing/selftests/bpf/test_sysctl.c b/tools/testing/selftests/bpf/test_sysctl.c
index a3bebd7c68dd..9e4986b03e95 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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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 +1379,26 @@ 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;
+ uint64_t value_num = 0;
uint8_t c, i;
if (buf_len > sizeof(value_num)) {
log_err("Value is too big (%zd) to use in fixup", buf_len);
return -1;
}
+ if (prog[insn_num].code != (BPF_LD | BPF_DW | BPF_IMM)) {
+ log_err("Can fixup only BPF_LD_IMM64 insns");
+ return -1;
+ }
for (i = 0; i < buf_len; ++i) {
c = buf[i];
value_num |= (c << i * 8);
}
+ value_num = __bpf_le64_to_cpu(value_num);
- prog[insn_num].imm = value_num;
+ prog[insn_num].imm = (__u32)value_num;
+ prog[insn_num + 1].imm = (__u32)(value_num >> 32);
return 0;
}
@@ -1499,6 +1540,7 @@ 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 +1549,7 @@ 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
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH bpf] selftests/bpf: fix endianness issues in test_sysctl
2019-08-15 12:25 [PATCH bpf] selftests/bpf: fix endianness issues in test_sysctl Ilya Leoshkevich
@ 2019-08-15 20:35 ` Andrey Ignatov
2019-08-16 10:21 ` Ilya Leoshkevich
2019-08-16 0:05 ` Yonghong Song
1 sibling, 1 reply; 6+ messages in thread
From: Andrey Ignatov @ 2019-08-15 20:35 UTC (permalink / raw)
To: Ilya Leoshkevich
Cc: Daniel Borkmann, Alexei Starovoitov, bpf, Heiko Carstens, Vasily Gorbik
Ilya Leoshkevich <iii@linux.ibm.com> [Thu, 2019-08-15 12:25 -0700]:
> 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_constant_ntohl,
> __bpf_constant_be64_to_cpu and __bpf_le64_to_cpu.
>
> 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>
I'm not sure about bpf_endian.h changes and will let others comment on
this part, but all fixes in test_sysctl.c (except one minor thing -- see
below) make sense. Thanks for fixing!
Acked-by: Andrey Ignatov <rdna@fb.com>
> ---
> tools/testing/selftests/bpf/bpf_endian.h | 4 +
> tools/testing/selftests/bpf/test_sysctl.c | 122 +++++++++++++++-------
> 2 files changed, 86 insertions(+), 40 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/bpf_endian.h b/tools/testing/selftests/bpf/bpf_endian.h
> index 05f036df8a4c..94175c993806 100644
> --- a/tools/testing/selftests/bpf/bpf_endian.h
> +++ b/tools/testing/selftests/bpf/bpf_endian.h
> @@ -29,6 +29,8 @@
> # define __bpf_htonl(x) __builtin_bswap32(x)
> # define __bpf_constant_ntohl(x) ___constant_swab32(x)
> # define __bpf_constant_htonl(x) ___constant_swab32(x)
> +# define __bpf_le64_to_cpu(x) (x)
> +# define __bpf_constant_be64_to_cpu(x) ___constant_swab64(x)
> #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
> # define __bpf_ntohs(x) (x)
> # define __bpf_htons(x) (x)
> @@ -38,6 +40,8 @@
> # define __bpf_htonl(x) (x)
> # define __bpf_constant_ntohl(x) (x)
> # define __bpf_constant_htonl(x) (x)
> +# define __bpf_le64_to_cpu(x) __swab64(x)
> +# define __bpf_constant_be64_to_cpu(x) (x)
> #else
> # error "Fix your compiler's __BYTE_ORDER__?!"
> #endif
> diff --git a/tools/testing/selftests/bpf/test_sysctl.c b/tools/testing/selftests/bpf/test_sysctl.c
> index a3bebd7c68dd..9e4986b03e95 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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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_constant_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 +1379,26 @@ 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;
> + uint64_t value_num = 0;
> uint8_t c, i;
>
> if (buf_len > sizeof(value_num)) {
> log_err("Value is too big (%zd) to use in fixup", buf_len);
> return -1;
> }
> + if (prog[insn_num].code != (BPF_LD | BPF_DW | BPF_IMM)) {
> + log_err("Can fixup only BPF_LD_IMM64 insns");
> + return -1;
> + }
>
> for (i = 0; i < buf_len; ++i) {
> c = buf[i];
> value_num |= (c << i * 8);
> }
> + value_num = __bpf_le64_to_cpu(value_num);
>
> - prog[insn_num].imm = value_num;
> + prog[insn_num].imm = (__u32)value_num;
> + prog[insn_num + 1].imm = (__u32)(value_num >> 32);
>
> return 0;
> }
> @@ -1499,6 +1540,7 @@ static int run_test_case(int cgfd, struct sysctl_test *test)
> goto err;
> }
>
> + errno = 0;
Yeah, access_sysctl() can return -1 w/o affecting errno, did it cause a
problem, or you set it just in case?
> if (access_sysctl(sysctl_path, test) == -1) {
> if (test->result == OP_EPERM && errno == EPERM)
> goto out;
> @@ -1507,7 +1549,7 @@ 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;
> }
>
--
Andrey Ignatov
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH bpf] selftests/bpf: fix endianness issues in test_sysctl
2019-08-15 12:25 [PATCH bpf] selftests/bpf: fix endianness issues in test_sysctl Ilya Leoshkevich
2019-08-15 20:35 ` Andrey Ignatov
@ 2019-08-16 0:05 ` Yonghong Song
2019-08-16 11:37 ` Ilya Leoshkevich
1 sibling, 1 reply; 6+ messages in thread
From: Yonghong Song @ 2019-08-16 0:05 UTC (permalink / raw)
To: Ilya Leoshkevich, Daniel Borkmann, Alexei Starovoitov
Cc: bpf, Heiko Carstens, Vasily Gorbik
On 8/15/19 5:25 AM, Ilya Leoshkevich 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_constant_ntohl,
> __bpf_constant_be64_to_cpu and __bpf_le64_to_cpu.
>
> 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/bpf_endian.h | 4 +
> tools/testing/selftests/bpf/test_sysctl.c | 122 +++++++++++++++-------
> 2 files changed, 86 insertions(+), 40 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/bpf_endian.h b/tools/testing/selftests/bpf/bpf_endian.h
> index 05f036df8a4c..94175c993806 100644
> --- a/tools/testing/selftests/bpf/bpf_endian.h
> +++ b/tools/testing/selftests/bpf/bpf_endian.h
> @@ -29,6 +29,8 @@
> # define __bpf_htonl(x) __builtin_bswap32(x)
> # define __bpf_constant_ntohl(x) ___constant_swab32(x)
> # define __bpf_constant_htonl(x) ___constant_swab32(x)
> +# define __bpf_le64_to_cpu(x)
Maybe we can remove this? See comments below.
(x)
> +# define __bpf_constant_be64_to_cpu(x) ___constant_swab64(x)
bpf_endian.h is used for both bpf program and native applications.
Could you make sure it works for bpf programs? It should be, but want to
double check.
The __constant_swab64 looks like a little bit expensive
for bpf programs compared to __builtin_bswap64. But
__builtin_bswap64 may not be available for all architectures, esp.
32bit system. So macro __bpf__ is required to use it.
In any case, bpf programs can directly use __builtin_bswap64,
so I am fine with __bpf_constant_be64_to_cpu().
> #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
> # define __bpf_ntohs(x) (x)
> # define __bpf_htons(x) (x)
> @@ -38,6 +40,8 @@
> # define __bpf_htonl(x) (x)
> # define __bpf_constant_ntohl(x) (x)
> # define __bpf_constant_htonl(x) (x)
> +# define __bpf_le64_to_cpu(x) __swab64(x)
> +# define __bpf_constant_be64_to_cpu(x) (x)
> #else
> # error "Fix your compiler's __BYTE_ORDER__?!"
> #endif
> diff --git a/tools/testing/selftests/bpf/test_sysctl.c b/tools/testing/selftests/bpf/test_sysctl.c
> index a3bebd7c68dd..9e4986b03e95 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_constant_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),
>
[....]
>
> BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
> @@ -1344,20 +1379,26 @@ 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;
> + uint64_t value_num = 0;
> uint8_t c, i;
>
> if (buf_len > sizeof(value_num)) {
> log_err("Value is too big (%zd) to use in fixup", buf_len);
> return -1;
> }
> + if (prog[insn_num].code != (BPF_LD | BPF_DW | BPF_IMM)) {
> + log_err("Can fixup only BPF_LD_IMM64 insns");
> + return -1;
> + }
>
> for (i = 0; i < buf_len; ++i) {
> c = buf[i];
> value_num |= (c << i * 8);
> }
> + value_num = __bpf_le64_to_cpu(value_num);
Can we avoid to use __bpf_le64_to_cpu?
Look like we already having the value in buf, can we just cast it
to get value_num. Note that bpf program and host always have
the same endianness. This way, no endianness conversion
is needed.
>
> - prog[insn_num].imm = value_num;
> + prog[insn_num].imm = (__u32)value_num;
> + prog[insn_num + 1].imm = (__u32)(value_num >> 32);
>
> return 0;
> }
> @@ -1499,6 +1540,7 @@ 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 +1549,7 @@ 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;
> }
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH bpf] selftests/bpf: fix endianness issues in test_sysctl
2019-08-15 20:35 ` Andrey Ignatov
@ 2019-08-16 10:21 ` Ilya Leoshkevich
0 siblings, 0 replies; 6+ messages in thread
From: Ilya Leoshkevich @ 2019-08-16 10:21 UTC (permalink / raw)
To: Andrey Ignatov
Cc: Daniel Borkmann, Alexei Starovoitov, bpf, Heiko Carstens, Vasily Gorbik
> Am 15.08.2019 um 22:35 schrieb Andrey Ignatov <rdna@fb.com>:
>
>> @@ -1344,20 +1379,26 @@ 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;
>> + uint64_t value_num = 0;
>> uint8_t c, i;
>>
>> if (buf_len > sizeof(value_num)) {
>> log_err("Value is too big (%zd) to use in fixup", buf_len);
>> return -1;
>> }
>> + if (prog[insn_num].code != (BPF_LD | BPF_DW | BPF_IMM)) {
>> + log_err("Can fixup only BPF_LD_IMM64 insns");
>> + return -1;
>> + }
>>
>> for (i = 0; i < buf_len; ++i) {
>> c = buf[i];
>> value_num |= (c << i * 8);
>> }
>> + value_num = __bpf_le64_to_cpu(value_num);
>>
>> - prog[insn_num].imm = value_num;
>> + prog[insn_num].imm = (__u32)value_num;
>> + prog[insn_num + 1].imm = (__u32)(value_num >> 32);
>>
>> return 0;
>> }
>> @@ -1499,6 +1540,7 @@ static int run_test_case(int cgfd, struct sysctl_test *test)
>> goto err;
>> }
>>
>> + errno = 0;
>
> Yeah, access_sysctl() can return -1 w/o affecting errno, did it cause a
> problem, or you set it just in case?
It's actually for another use case: if access_sysctl() unexpectedly
returns 0, log_err() will misleadingly print a "random" errno. With this
change, it would print "Unexpected success: errno: None", which makes
sense to me.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH bpf] selftests/bpf: fix endianness issues in test_sysctl
2019-08-16 0:05 ` Yonghong Song
@ 2019-08-16 11:37 ` Ilya Leoshkevich
2019-08-17 0:06 ` Yonghong Song
0 siblings, 1 reply; 6+ messages in thread
From: Ilya Leoshkevich @ 2019-08-16 11:37 UTC (permalink / raw)
To: Yonghong Song
Cc: Daniel Borkmann, Alexei Starovoitov, bpf, Heiko Carstens, Vasily Gorbik
> Am 16.08.2019 um 02:05 schrieb Yonghong Song <yhs@fb.com>:
>
>> +# define __bpf_constant_be64_to_cpu(x) ___constant_swab64(x)
>
> bpf_endian.h is used for both bpf program and native applications.
> Could you make sure it works for bpf programs? It should be, but want to
> double check.
Yes:
#include <linux/compiler_attributes.h>
#include "bpf_endian.h"
u64 answer() { return __bpf_constant_be64_to_cpu(42); }
compiles to
r0 = 3026418949592973312 ll
exit
on x86.
> The __constant_swab64 looks like a little bit expensive
> for bpf programs compared to __builtin_bswap64. But
> __builtin_bswap64 may not be available for all architectures, esp.
> 32bit system. So macro __bpf__ is required to use it.
Isn't ___constant_swab64 supposed to be 100% compile-time?
Also, I think __builtin_bswap64 should be available everywhere for
userspace. At least the following test does not indicate any problems:
for cc in "x86_64-linux-gnu-gcc -m32" \
"x86_64-linux-gnu-gcc -m64" \
"aarch64-linux-gnu-gcc" \
"arm-linux-gnueabihf-gcc" \
"mips64el-linux-gnuabi64-gcc" \
"powerpc64le-linux-gnu-gcc -m32" \
"s390x-linux-gnu-gcc -m31" \
"s390x-linux-gnu-gcc -m64" \
"sparc64-linux-gnu-gcc -m32" \
"sparc64-linux-gnu-gcc -m64" \
"clang -target bpf -m32" \
"clang -target bpf -m64"; do
echo "*** $cc ***"
echo "long long f(long long x) { return __builtin_bswap64(x); }" | \
$cc -x c -S - -O3 -o -;
done
Only sparc64 doesn't support it directly, but then it just calls
libgcc's __bswapdi2. This might not be ok only for kernel native code
(though even there we have e.g. arch/arm/lib/bswapsdi2.S), but I don't
think this header is used in such context anyway.
>>
>> BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
>> @@ -1344,20 +1379,26 @@ 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;
>> + uint64_t value_num = 0;
>> uint8_t c, i;
>>
>> if (buf_len > sizeof(value_num)) {
>> log_err("Value is too big (%zd) to use in fixup", buf_len);
>> return -1;
>> }
>> + if (prog[insn_num].code != (BPF_LD | BPF_DW | BPF_IMM)) {
>> + log_err("Can fixup only BPF_LD_IMM64 insns");
>> + return -1;
>> + }
>>
>> for (i = 0; i < buf_len; ++i) {
>> c = buf[i];
>> value_num |= (c << i * 8);
>> }
>> + value_num = __bpf_le64_to_cpu(value_num);
>
> Can we avoid to use __bpf_le64_to_cpu?
> Look like we already having the value in buf, can we just cast it
> to get value_num. Note that bpf program and host always have
> the same endianness. This way, no endianness conversion
> is needed.
I think this might be dangerous in case buf is smaller than 8 bytes.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH bpf] selftests/bpf: fix endianness issues in test_sysctl
2019-08-16 11:37 ` Ilya Leoshkevich
@ 2019-08-17 0:06 ` Yonghong Song
0 siblings, 0 replies; 6+ messages in thread
From: Yonghong Song @ 2019-08-17 0:06 UTC (permalink / raw)
To: Ilya Leoshkevich
Cc: Daniel Borkmann, Alexei Starovoitov, bpf, Heiko Carstens, Vasily Gorbik
On 8/16/19 4:37 AM, Ilya Leoshkevich wrote:
>> Am 16.08.2019 um 02:05 schrieb Yonghong Song <yhs@fb.com>:
>>
>>> +# define __bpf_constant_be64_to_cpu(x) ___constant_swab64(x)
>>
>> bpf_endian.h is used for both bpf program and native applications.
>> Could you make sure it works for bpf programs? It should be, but want to
>> double check.
>
> Yes:
>
> #include <linux/compiler_attributes.h>
> #include "bpf_endian.h"
> u64 answer() { return __bpf_constant_be64_to_cpu(42); }
>
> compiles to
>
> r0 = 3026418949592973312 ll
> exit
>
> on x86.
>
>> The __constant_swab64 looks like a little bit expensive
>> for bpf programs compared to __builtin_bswap64. But
>> __builtin_bswap64 may not be available for all architectures, esp.
>> 32bit system. So macro __bpf__ is required to use it.
>
> Isn't ___constant_swab64 supposed to be 100% compile-time?
>
> Also, I think __builtin_bswap64 should be available everywhere for
> userspace. At least the following test does not indicate any problems:
>
> for cc in "x86_64-linux-gnu-gcc -m32" \
> "x86_64-linux-gnu-gcc -m64" \
> "aarch64-linux-gnu-gcc" \
> "arm-linux-gnueabihf-gcc" \
> "mips64el-linux-gnuabi64-gcc" \
> "powerpc64le-linux-gnu-gcc -m32" \
> "s390x-linux-gnu-gcc -m31" \
> "s390x-linux-gnu-gcc -m64" \
> "sparc64-linux-gnu-gcc -m32" \
> "sparc64-linux-gnu-gcc -m64" \
> "clang -target bpf -m32" \
> "clang -target bpf -m64"; do
> echo "*** $cc ***"
> echo "long long f(long long x) { return __builtin_bswap64(x); }" | \
> $cc -x c -S - -O3 -o -;
> done
>
> Only sparc64 doesn't support it directly, but then it just calls
> libgcc's __bswapdi2. This might not be ok only for kernel native code
> (though even there we have e.g. arch/arm/lib/bswapsdi2.S), but I don't
> think this header is used in such context anyway.
Great to know. Maybe we can define
__bpf_be64_to_cpu // using __builtin_bswap64
__bpf_constant_be64_to_cpu // use your above definition
bpf_be64_to_cpu(x) // check whether x is __builtin_constant_p()
// or not, and then call the above two.
bpf_be64_to_cpu() can be used in test_sysctl.c.
>
>>>
>>> BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
>>> @@ -1344,20 +1379,26 @@ 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;
>>> + uint64_t value_num = 0;
>>> uint8_t c, i;
>>>
>>> if (buf_len > sizeof(value_num)) {
>>> log_err("Value is too big (%zd) to use in fixup", buf_len);
>>> return -1;
>>> }
>>> + if (prog[insn_num].code != (BPF_LD | BPF_DW | BPF_IMM)) {
>>> + log_err("Can fixup only BPF_LD_IMM64 insns");
>>> + return -1;
>>> + }
>>>
>>> for (i = 0; i < buf_len; ++i) {
>>> c = buf[i];
>>> value_num |= (c << i * 8);
>>> }
>>> + value_num = __bpf_le64_to_cpu(value_num);
>>
>> Can we avoid to use __bpf_le64_to_cpu?
>> Look like we already having the value in buf, can we just cast it
>> to get value_num. Note that bpf program and host always have
>> the same endianness. This way, no endianness conversion
>> is needed.
>
> I think this might be dangerous in case buf is smaller than 8 bytes.
Instead of calculating the value_num as the above, maybe we could
do something like below:
union {
uint8_t values[sizeof(__u64)];
__u64 val;
} u = {};
memcpy(u.values, buf, buf_len);
/* u.val should hold a u64 value which you can use
* for LD_IMM64 can use.
*/
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2019-08-17 0:06 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2019-08-15 12:25 [PATCH bpf] selftests/bpf: fix endianness issues in test_sysctl Ilya Leoshkevich
2019-08-15 20:35 ` Andrey Ignatov
2019-08-16 10:21 ` Ilya Leoshkevich
2019-08-16 0:05 ` Yonghong Song
2019-08-16 11:37 ` Ilya Leoshkevich
2019-08-17 0:06 ` Yonghong Song
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