linux-stable/tools/testing/selftests/bpf/test_verifier.c
Gary Lin 79d1b684e2 selftests/bpf: Add verifier tests for x64 jit jump padding
There are 3 tests added into verifier's jit tests to trigger x64
jit jump padding.

The first test can be represented as the following assembly code:

      1: bpf_call bpf_get_prandom_u32
      2: if r0 == 1 goto pc+128
      3: if r0 == 2 goto pc+128
         ...
    129: if r0 == 128 goto pc+128
    130: goto pc+128
    131: goto pc+127
         ...
    256: goto pc+2
    257: goto pc+1
    258: r0 = 1
    259: ret

We first store a random number to r0 and add the corresponding
conditional jumps (2~129) to make verifier believe that those jump
instructions from 130 to 257 are reachable. When the program is sent to
x64 jit, it starts to optimize out the NOP jumps backwards from 257.
Since there are 128 such jumps, the program easily reaches 15 passes and
triggers jump padding.

Here is the x64 jit code of the first test:

      0:    0f 1f 44 00 00          nop    DWORD PTR [rax+rax*1+0x0]
      5:    66 90                   xchg   ax,ax
      7:    55                      push   rbp
      8:    48 89 e5                mov    rbp,rsp
      b:    e8 4c 90 75 e3          call   0xffffffffe375905c
     10:    48 83 f8 01             cmp    rax,0x1
     14:    0f 84 fe 04 00 00       je     0x518
     1a:    48 83 f8 02             cmp    rax,0x2
     1e:    0f 84 f9 04 00 00       je     0x51d
      ...
     f6:    48 83 f8 18             cmp    rax,0x18
     fa:    0f 84 8b 04 00 00       je     0x58b
    100:    48 83 f8 19             cmp    rax,0x19
    104:    0f 84 86 04 00 00       je     0x590
    10a:    48 83 f8 1a             cmp    rax,0x1a
    10e:    0f 84 81 04 00 00       je     0x595
      ...
    500:    0f 84 83 01 00 00       je     0x689
    506:    48 81 f8 80 00 00 00    cmp    rax,0x80
    50d:    0f 84 76 01 00 00       je     0x689
    513:    e9 71 01 00 00          jmp    0x689
    518:    e9 6c 01 00 00          jmp    0x689
      ...
    5fe:    e9 86 00 00 00          jmp    0x689
    603:    e9 81 00 00 00          jmp    0x689
    608:    0f 1f 00                nop    DWORD PTR [rax]
    60b:    eb 7c                   jmp    0x689
    60d:    eb 7a                   jmp    0x689
      ...
    683:    eb 04                   jmp    0x689
    685:    eb 02                   jmp    0x689
    687:    66 90                   xchg   ax,ax
    689:    b8 01 00 00 00          mov    eax,0x1
    68e:    c9                      leave
    68f:    c3                      ret

As expected, a 3 bytes NOPs is inserted at 608 due to the transition
from imm32 jmp to imm8 jmp. A 2 bytes NOPs is also inserted at 687 to
replace a NOP jump.

The second test case is tricky. Here is the assembly code:

       1: bpf_call bpf_get_prandom_u32
       2: if r0 == 1 goto pc+2048
       3: if r0 == 2 goto pc+2048
       ...
    2049: if r0 == 2048 goto pc+2048
    2050: goto pc+2048
    2051: goto pc+16
    2052: goto pc+15
       ...
    2064: goto pc+3
    2065: goto pc+2
    2066: goto pc+1
       ...
       [repeat "goto pc+16".."goto pc+1" 127 times]
       ...
    4099: r0 = 2
    4100: ret

There are 4 major parts of the program.
1) 1~2049: Those are instructions to make 2050~4098 reachable. Some of
           them also could generate the padding for jmp_cond.
2) 2050: This is the target instruction for the imm32 nop jmp padding.
3) 2051~4098: The repeated "goto 1~16" instructions are designed to be
              consumed by the nop jmp optimization. In the end, those
              instrucitons become 128 continuous 0 offset jmp and are
              optimized out in 1 pass, and this make insn 2050 an imm32
              nop jmp in the next pass, so that we can trigger the
              5 bytes padding.
4) 4099~4100: Those are the instructions to end the program.

The x64 jit code is like this:

       0:       0f 1f 44 00 00          nop    DWORD PTR [rax+rax*1+0x0]
       5:       66 90                   xchg   ax,ax
       7:       55                      push   rbp
       8:       48 89 e5                mov    rbp,rsp
       b:       e8 bc 7b d5 d3          call   0xffffffffd3d57bcc
      10:       48 83 f8 01             cmp    rax,0x1
      14:       0f 84 7e 66 00 00       je     0x6698
      1a:       48 83 f8 02             cmp    rax,0x2
      1e:       0f 84 74 66 00 00       je     0x6698
      24:       48 83 f8 03             cmp    rax,0x3
      28:       0f 84 6a 66 00 00       je     0x6698
      2e:       48 83 f8 04             cmp    rax,0x4
      32:       0f 84 60 66 00 00       je     0x6698
      38:       48 83 f8 05             cmp    rax,0x5
      3c:       0f 84 56 66 00 00       je     0x6698
      42:       48 83 f8 06             cmp    rax,0x6
      46:       0f 84 4c 66 00 00       je     0x6698
      ...
    666c:       48 81 f8 fe 07 00 00    cmp    rax,0x7fe
    6673:       0f 1f 40 00             nop    DWORD PTR [rax+0x0]
    6677:       74 1f                   je     0x6698
    6679:       48 81 f8 ff 07 00 00    cmp    rax,0x7ff
    6680:       0f 1f 40 00             nop    DWORD PTR [rax+0x0]
    6684:       74 12                   je     0x6698
    6686:       48 81 f8 00 08 00 00    cmp    rax,0x800
    668d:       0f 1f 40 00             nop    DWORD PTR [rax+0x0]
    6691:       74 05                   je     0x6698
    6693:       0f 1f 44 00 00          nop    DWORD PTR [rax+rax*1+0x0]
    6698:       b8 02 00 00 00          mov    eax,0x2
    669d:       c9                      leave
    669e:       c3                      ret

Since insn 2051~4098 are optimized out right before the padding pass,
there are several conditional jumps from the first part are replaced with
imm8 jmp_cond, and this triggers the 4 bytes padding, for example at
6673, 6680, and 668d. On the other hand, Insn 2050 is replaced with the
5 bytes nops at 6693.

The third test is to invoke the first and second tests as subprogs to test
bpf2bpf. Per the system log, there was one more jit happened with only
one pass and the same jit code was produced.

v4:
  - Add the second test case which triggers jmp_cond padding and imm32 nop
    jmp padding.
  - Add the new test case as another subprog

Signed-off-by: Gary Lin <glin@suse.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210119102501.511-4-glin@suse.com
2021-01-20 14:13:52 -08:00

1348 lines
35 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Testsuite for eBPF verifier
*
* Copyright (c) 2014 PLUMgrid, http://plumgrid.com
* Copyright (c) 2017 Facebook
* Copyright (c) 2018 Covalent IO, Inc. http://covalent.io
*/
#include <endian.h>
#include <asm/types.h>
#include <linux/types.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stddef.h>
#include <stdbool.h>
#include <sched.h>
#include <limits.h>
#include <assert.h>
#include <sys/capability.h>
#include <linux/unistd.h>
#include <linux/filter.h>
#include <linux/bpf_perf_event.h>
#include <linux/bpf.h>
#include <linux/if_ether.h>
#include <linux/btf.h>
#include <bpf/bpf.h>
#include <bpf/libbpf.h>
#ifdef HAVE_GENHDR
# include "autoconf.h"
#else
# if defined(__i386) || defined(__x86_64) || defined(__s390x__) || defined(__aarch64__)
# define CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS 1
# endif
#endif
#include "bpf_rlimit.h"
#include "bpf_rand.h"
#include "bpf_util.h"
#include "test_btf.h"
#include "../../../include/linux/filter.h"
#define MAX_INSNS BPF_MAXINSNS
#define MAX_TEST_INSNS 1000000
#define MAX_FIXUPS 8
#define MAX_NR_MAPS 21
#define MAX_TEST_RUNS 8
#define POINTER_VALUE 0xcafe4all
#define TEST_DATA_LEN 64
#define F_NEEDS_EFFICIENT_UNALIGNED_ACCESS (1 << 0)
#define F_LOAD_WITH_STRICT_ALIGNMENT (1 << 1)
#define UNPRIV_SYSCTL "kernel/unprivileged_bpf_disabled"
static bool unpriv_disabled = false;
static int skips;
static bool verbose = false;
struct bpf_test {
const char *descr;
struct bpf_insn insns[MAX_INSNS];
struct bpf_insn *fill_insns;
int fixup_map_hash_8b[MAX_FIXUPS];
int fixup_map_hash_48b[MAX_FIXUPS];
int fixup_map_hash_16b[MAX_FIXUPS];
int fixup_map_array_48b[MAX_FIXUPS];
int fixup_map_sockmap[MAX_FIXUPS];
int fixup_map_sockhash[MAX_FIXUPS];
int fixup_map_xskmap[MAX_FIXUPS];
int fixup_map_stacktrace[MAX_FIXUPS];
int fixup_prog1[MAX_FIXUPS];
int fixup_prog2[MAX_FIXUPS];
int fixup_map_in_map[MAX_FIXUPS];
int fixup_cgroup_storage[MAX_FIXUPS];
int fixup_percpu_cgroup_storage[MAX_FIXUPS];
int fixup_map_spin_lock[MAX_FIXUPS];
int fixup_map_array_ro[MAX_FIXUPS];
int fixup_map_array_wo[MAX_FIXUPS];
int fixup_map_array_small[MAX_FIXUPS];
int fixup_sk_storage_map[MAX_FIXUPS];
int fixup_map_event_output[MAX_FIXUPS];
int fixup_map_reuseport_array[MAX_FIXUPS];
int fixup_map_ringbuf[MAX_FIXUPS];
const char *errstr;
const char *errstr_unpriv;
uint32_t insn_processed;
int prog_len;
enum {
UNDEF,
ACCEPT,
REJECT,
VERBOSE_ACCEPT,
} result, result_unpriv;
enum bpf_prog_type prog_type;
uint8_t flags;
void (*fill_helper)(struct bpf_test *self);
uint8_t runs;
#define bpf_testdata_struct_t \
struct { \
uint32_t retval, retval_unpriv; \
union { \
__u8 data[TEST_DATA_LEN]; \
__u64 data64[TEST_DATA_LEN / 8]; \
}; \
}
union {
bpf_testdata_struct_t;
bpf_testdata_struct_t retvals[MAX_TEST_RUNS];
};
enum bpf_attach_type expected_attach_type;
const char *kfunc;
};
/* Note we want this to be 64 bit aligned so that the end of our array is
* actually the end of the structure.
*/
#define MAX_ENTRIES 11
struct test_val {
unsigned int index;
int foo[MAX_ENTRIES];
};
struct other_val {
long long foo;
long long bar;
};
static void bpf_fill_ld_abs_vlan_push_pop(struct bpf_test *self)
{
/* test: {skb->data[0], vlan_push} x 51 + {skb->data[0], vlan_pop} x 51 */
#define PUSH_CNT 51
/* jump range is limited to 16 bit. PUSH_CNT of ld_abs needs room */
unsigned int len = (1 << 15) - PUSH_CNT * 2 * 5 * 6;
struct bpf_insn *insn = self->fill_insns;
int i = 0, j, k = 0;
insn[i++] = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
loop:
for (j = 0; j < PUSH_CNT; j++) {
insn[i++] = BPF_LD_ABS(BPF_B, 0);
/* jump to error label */
insn[i] = BPF_JMP32_IMM(BPF_JNE, BPF_REG_0, 0x34, len - i - 3);
i++;
insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
insn[i++] = BPF_MOV64_IMM(BPF_REG_2, 1);
insn[i++] = BPF_MOV64_IMM(BPF_REG_3, 2);
insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_skb_vlan_push),
insn[i] = BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, len - i - 3);
i++;
}
for (j = 0; j < PUSH_CNT; j++) {
insn[i++] = BPF_LD_ABS(BPF_B, 0);
insn[i] = BPF_JMP32_IMM(BPF_JNE, BPF_REG_0, 0x34, len - i - 3);
i++;
insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_skb_vlan_pop),
insn[i] = BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, len - i - 3);
i++;
}
if (++k < 5)
goto loop;
for (; i < len - 3; i++)
insn[i] = BPF_ALU64_IMM(BPF_MOV, BPF_REG_0, 0xbef);
insn[len - 3] = BPF_JMP_A(1);
/* error label */
insn[len - 2] = BPF_MOV32_IMM(BPF_REG_0, 0);
insn[len - 1] = BPF_EXIT_INSN();
self->prog_len = len;
}
static void bpf_fill_jump_around_ld_abs(struct bpf_test *self)
{
struct bpf_insn *insn = self->fill_insns;
/* jump range is limited to 16 bit. every ld_abs is replaced by 6 insns,
* but on arches like arm, ppc etc, there will be one BPF_ZEXT inserted
* to extend the error value of the inlined ld_abs sequence which then
* contains 7 insns. so, set the dividend to 7 so the testcase could
* work on all arches.
*/
unsigned int len = (1 << 15) / 7;
int i = 0;
insn[i++] = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
insn[i++] = BPF_LD_ABS(BPF_B, 0);
insn[i] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 10, len - i - 2);
i++;
while (i < len - 1)
insn[i++] = BPF_LD_ABS(BPF_B, 1);
insn[i] = BPF_EXIT_INSN();
self->prog_len = i + 1;
}
static void bpf_fill_rand_ld_dw(struct bpf_test *self)
{
struct bpf_insn *insn = self->fill_insns;
uint64_t res = 0;
int i = 0;
insn[i++] = BPF_MOV32_IMM(BPF_REG_0, 0);
while (i < self->retval) {
uint64_t val = bpf_semi_rand_get();
struct bpf_insn tmp[2] = { BPF_LD_IMM64(BPF_REG_1, val) };
res ^= val;
insn[i++] = tmp[0];
insn[i++] = tmp[1];
insn[i++] = BPF_ALU64_REG(BPF_XOR, BPF_REG_0, BPF_REG_1);
}
insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_0);
insn[i++] = BPF_ALU64_IMM(BPF_RSH, BPF_REG_1, 32);
insn[i++] = BPF_ALU64_REG(BPF_XOR, BPF_REG_0, BPF_REG_1);
insn[i] = BPF_EXIT_INSN();
self->prog_len = i + 1;
res ^= (res >> 32);
self->retval = (uint32_t)res;
}
#define MAX_JMP_SEQ 8192
/* test the sequence of 8k jumps */
static void bpf_fill_scale1(struct bpf_test *self)
{
struct bpf_insn *insn = self->fill_insns;
int i = 0, k = 0;
insn[i++] = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
/* test to check that the long sequence of jumps is acceptable */
while (k++ < MAX_JMP_SEQ) {
insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_prandom_u32);
insn[i++] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, bpf_semi_rand_get(), 2);
insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_10);
insn[i++] = BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6,
-8 * (k % 64 + 1));
}
/* is_state_visited() doesn't allocate state for pruning for every jump.
* Hence multiply jmps by 4 to accommodate that heuristic
*/
while (i < MAX_TEST_INSNS - MAX_JMP_SEQ * 4)
insn[i++] = BPF_ALU64_IMM(BPF_MOV, BPF_REG_0, 42);
insn[i] = BPF_EXIT_INSN();
self->prog_len = i + 1;
self->retval = 42;
}
/* test the sequence of 8k jumps in inner most function (function depth 8)*/
static void bpf_fill_scale2(struct bpf_test *self)
{
struct bpf_insn *insn = self->fill_insns;
int i = 0, k = 0;
#define FUNC_NEST 7
for (k = 0; k < FUNC_NEST; k++) {
insn[i++] = BPF_CALL_REL(1);
insn[i++] = BPF_EXIT_INSN();
}
insn[i++] = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
/* test to check that the long sequence of jumps is acceptable */
k = 0;
while (k++ < MAX_JMP_SEQ) {
insn[i++] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_prandom_u32);
insn[i++] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, bpf_semi_rand_get(), 2);
insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_10);
insn[i++] = BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_6,
-8 * (k % (64 - 4 * FUNC_NEST) + 1));
}
while (i < MAX_TEST_INSNS - MAX_JMP_SEQ * 4)
insn[i++] = BPF_ALU64_IMM(BPF_MOV, BPF_REG_0, 42);
insn[i] = BPF_EXIT_INSN();
self->prog_len = i + 1;
self->retval = 42;
}
static void bpf_fill_scale(struct bpf_test *self)
{
switch (self->retval) {
case 1:
return bpf_fill_scale1(self);
case 2:
return bpf_fill_scale2(self);
default:
self->prog_len = 0;
break;
}
}
static int bpf_fill_torturous_jumps_insn_1(struct bpf_insn *insn)
{
unsigned int len = 259, hlen = 128;
int i;
insn[0] = BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32);
for (i = 1; i <= hlen; i++) {
insn[i] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, i, hlen);
insn[i + hlen] = BPF_JMP_A(hlen - i);
}
insn[len - 2] = BPF_MOV64_IMM(BPF_REG_0, 1);
insn[len - 1] = BPF_EXIT_INSN();
return len;
}
static int bpf_fill_torturous_jumps_insn_2(struct bpf_insn *insn)
{
unsigned int len = 4100, jmp_off = 2048;
int i, j;
insn[0] = BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32);
for (i = 1; i <= jmp_off; i++) {
insn[i] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, i, jmp_off);
}
insn[i++] = BPF_JMP_A(jmp_off);
for (; i <= jmp_off * 2 + 1; i+=16) {
for (j = 0; j < 16; j++) {
insn[i + j] = BPF_JMP_A(16 - j - 1);
}
}
insn[len - 2] = BPF_MOV64_IMM(BPF_REG_0, 2);
insn[len - 1] = BPF_EXIT_INSN();
return len;
}
static void bpf_fill_torturous_jumps(struct bpf_test *self)
{
struct bpf_insn *insn = self->fill_insns;
int i = 0;
switch (self->retval) {
case 1:
self->prog_len = bpf_fill_torturous_jumps_insn_1(insn);
return;
case 2:
self->prog_len = bpf_fill_torturous_jumps_insn_2(insn);
return;
case 3:
/* main */
insn[i++] = BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 4);
insn[i++] = BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 262);
insn[i++] = BPF_ST_MEM(BPF_B, BPF_REG_10, -32, 0);
insn[i++] = BPF_MOV64_IMM(BPF_REG_0, 3);
insn[i++] = BPF_EXIT_INSN();
/* subprog 1 */
i += bpf_fill_torturous_jumps_insn_1(insn + i);
/* subprog 2 */
i += bpf_fill_torturous_jumps_insn_2(insn + i);
self->prog_len = i;
return;
default:
self->prog_len = 0;
break;
}
}
/* BPF_SK_LOOKUP contains 13 instructions, if you need to fix up maps */
#define BPF_SK_LOOKUP(func) \
/* struct bpf_sock_tuple tuple = {} */ \
BPF_MOV64_IMM(BPF_REG_2, 0), \
BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_2, -8), \
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -16), \
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -24), \
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -32), \
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -40), \
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -48), \
/* sk = func(ctx, &tuple, sizeof tuple, 0, 0) */ \
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), \
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -48), \
BPF_MOV64_IMM(BPF_REG_3, sizeof(struct bpf_sock_tuple)), \
BPF_MOV64_IMM(BPF_REG_4, 0), \
BPF_MOV64_IMM(BPF_REG_5, 0), \
BPF_EMIT_CALL(BPF_FUNC_ ## func)
/* BPF_DIRECT_PKT_R2 contains 7 instructions, it initializes default return
* value into 0 and does necessary preparation for direct packet access
* through r2. The allowed access range is 8 bytes.
*/
#define BPF_DIRECT_PKT_R2 \
BPF_MOV64_IMM(BPF_REG_0, 0), \
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, \
offsetof(struct __sk_buff, data)), \
BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, \
offsetof(struct __sk_buff, data_end)), \
BPF_MOV64_REG(BPF_REG_4, BPF_REG_2), \
BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 8), \
BPF_JMP_REG(BPF_JLE, BPF_REG_4, BPF_REG_3, 1), \
BPF_EXIT_INSN()
/* BPF_RAND_UEXT_R7 contains 4 instructions, it initializes R7 into a random
* positive u32, and zero-extend it into 64-bit.
*/
#define BPF_RAND_UEXT_R7 \
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, \
BPF_FUNC_get_prandom_u32), \
BPF_MOV64_REG(BPF_REG_7, BPF_REG_0), \
BPF_ALU64_IMM(BPF_LSH, BPF_REG_7, 33), \
BPF_ALU64_IMM(BPF_RSH, BPF_REG_7, 33)
/* BPF_RAND_SEXT_R7 contains 5 instructions, it initializes R7 into a random
* negative u32, and sign-extend it into 64-bit.
*/
#define BPF_RAND_SEXT_R7 \
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, \
BPF_FUNC_get_prandom_u32), \
BPF_MOV64_REG(BPF_REG_7, BPF_REG_0), \
BPF_ALU64_IMM(BPF_OR, BPF_REG_7, 0x80000000), \
BPF_ALU64_IMM(BPF_LSH, BPF_REG_7, 32), \
BPF_ALU64_IMM(BPF_ARSH, BPF_REG_7, 32)
static struct bpf_test tests[] = {
#define FILL_ARRAY
#include <verifier/tests.h>
#undef FILL_ARRAY
};
static int probe_filter_length(const struct bpf_insn *fp)
{
int len;
for (len = MAX_INSNS - 1; len > 0; --len)
if (fp[len].code != 0 || fp[len].imm != 0)
break;
return len + 1;
}
static bool skip_unsupported_map(enum bpf_map_type map_type)
{
if (!bpf_probe_map_type(map_type, 0)) {
printf("SKIP (unsupported map type %d)\n", map_type);
skips++;
return true;
}
return false;
}
static int __create_map(uint32_t type, uint32_t size_key,
uint32_t size_value, uint32_t max_elem,
uint32_t extra_flags)
{
int fd;
fd = bpf_create_map(type, size_key, size_value, max_elem,
(type == BPF_MAP_TYPE_HASH ?
BPF_F_NO_PREALLOC : 0) | extra_flags);
if (fd < 0) {
if (skip_unsupported_map(type))
return -1;
printf("Failed to create hash map '%s'!\n", strerror(errno));
}
return fd;
}
static int create_map(uint32_t type, uint32_t size_key,
uint32_t size_value, uint32_t max_elem)
{
return __create_map(type, size_key, size_value, max_elem, 0);
}
static void update_map(int fd, int index)
{
struct test_val value = {
.index = (6 + 1) * sizeof(int),
.foo[6] = 0xabcdef12,
};
assert(!bpf_map_update_elem(fd, &index, &value, 0));
}
static int create_prog_dummy_simple(enum bpf_prog_type prog_type, int ret)
{
struct bpf_insn prog[] = {
BPF_MOV64_IMM(BPF_REG_0, ret),
BPF_EXIT_INSN(),
};
return bpf_load_program(prog_type, prog,
ARRAY_SIZE(prog), "GPL", 0, NULL, 0);
}
static int create_prog_dummy_loop(enum bpf_prog_type prog_type, int mfd,
int idx, int ret)
{
struct bpf_insn prog[] = {
BPF_MOV64_IMM(BPF_REG_3, idx),
BPF_LD_MAP_FD(BPF_REG_2, mfd),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_tail_call),
BPF_MOV64_IMM(BPF_REG_0, ret),
BPF_EXIT_INSN(),
};
return bpf_load_program(prog_type, prog,
ARRAY_SIZE(prog), "GPL", 0, NULL, 0);
}
static int create_prog_array(enum bpf_prog_type prog_type, uint32_t max_elem,
int p1key, int p2key, int p3key)
{
int mfd, p1fd, p2fd, p3fd;
mfd = bpf_create_map(BPF_MAP_TYPE_PROG_ARRAY, sizeof(int),
sizeof(int), max_elem, 0);
if (mfd < 0) {
if (skip_unsupported_map(BPF_MAP_TYPE_PROG_ARRAY))
return -1;
printf("Failed to create prog array '%s'!\n", strerror(errno));
return -1;
}
p1fd = create_prog_dummy_simple(prog_type, 42);
p2fd = create_prog_dummy_loop(prog_type, mfd, p2key, 41);
p3fd = create_prog_dummy_simple(prog_type, 24);
if (p1fd < 0 || p2fd < 0 || p3fd < 0)
goto err;
if (bpf_map_update_elem(mfd, &p1key, &p1fd, BPF_ANY) < 0)
goto err;
if (bpf_map_update_elem(mfd, &p2key, &p2fd, BPF_ANY) < 0)
goto err;
if (bpf_map_update_elem(mfd, &p3key, &p3fd, BPF_ANY) < 0) {
err:
close(mfd);
mfd = -1;
}
close(p3fd);
close(p2fd);
close(p1fd);
return mfd;
}
static int create_map_in_map(void)
{
int inner_map_fd, outer_map_fd;
inner_map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(int),
sizeof(int), 1, 0);
if (inner_map_fd < 0) {
if (skip_unsupported_map(BPF_MAP_TYPE_ARRAY))
return -1;
printf("Failed to create array '%s'!\n", strerror(errno));
return inner_map_fd;
}
outer_map_fd = bpf_create_map_in_map(BPF_MAP_TYPE_ARRAY_OF_MAPS, NULL,
sizeof(int), inner_map_fd, 1, 0);
if (outer_map_fd < 0) {
if (skip_unsupported_map(BPF_MAP_TYPE_ARRAY_OF_MAPS))
return -1;
printf("Failed to create array of maps '%s'!\n",
strerror(errno));
}
close(inner_map_fd);
return outer_map_fd;
}
static int create_cgroup_storage(bool percpu)
{
enum bpf_map_type type = percpu ? BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE :
BPF_MAP_TYPE_CGROUP_STORAGE;
int fd;
fd = bpf_create_map(type, sizeof(struct bpf_cgroup_storage_key),
TEST_DATA_LEN, 0, 0);
if (fd < 0) {
if (skip_unsupported_map(type))
return -1;
printf("Failed to create cgroup storage '%s'!\n",
strerror(errno));
}
return fd;
}
/* struct bpf_spin_lock {
* int val;
* };
* struct val {
* int cnt;
* struct bpf_spin_lock l;
* };
*/
static const char btf_str_sec[] = "\0bpf_spin_lock\0val\0cnt\0l";
static __u32 btf_raw_types[] = {
/* int */
BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
/* struct bpf_spin_lock */ /* [2] */
BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 1), 4),
BTF_MEMBER_ENC(15, 1, 0), /* int val; */
/* struct val */ /* [3] */
BTF_TYPE_ENC(15, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), 8),
BTF_MEMBER_ENC(19, 1, 0), /* int cnt; */
BTF_MEMBER_ENC(23, 2, 32),/* struct bpf_spin_lock l; */
};
static int load_btf(void)
{
struct btf_header hdr = {
.magic = BTF_MAGIC,
.version = BTF_VERSION,
.hdr_len = sizeof(struct btf_header),
.type_len = sizeof(btf_raw_types),
.str_off = sizeof(btf_raw_types),
.str_len = sizeof(btf_str_sec),
};
void *ptr, *raw_btf;
int btf_fd;
ptr = raw_btf = malloc(sizeof(hdr) + sizeof(btf_raw_types) +
sizeof(btf_str_sec));
memcpy(ptr, &hdr, sizeof(hdr));
ptr += sizeof(hdr);
memcpy(ptr, btf_raw_types, hdr.type_len);
ptr += hdr.type_len;
memcpy(ptr, btf_str_sec, hdr.str_len);
ptr += hdr.str_len;
btf_fd = bpf_load_btf(raw_btf, ptr - raw_btf, 0, 0, 0);
free(raw_btf);
if (btf_fd < 0)
return -1;
return btf_fd;
}
static int create_map_spin_lock(void)
{
struct bpf_create_map_attr attr = {
.name = "test_map",
.map_type = BPF_MAP_TYPE_ARRAY,
.key_size = 4,
.value_size = 8,
.max_entries = 1,
.btf_key_type_id = 1,
.btf_value_type_id = 3,
};
int fd, btf_fd;
btf_fd = load_btf();
if (btf_fd < 0)
return -1;
attr.btf_fd = btf_fd;
fd = bpf_create_map_xattr(&attr);
if (fd < 0)
printf("Failed to create map with spin_lock\n");
return fd;
}
static int create_sk_storage_map(void)
{
struct bpf_create_map_attr attr = {
.name = "test_map",
.map_type = BPF_MAP_TYPE_SK_STORAGE,
.key_size = 4,
.value_size = 8,
.max_entries = 0,
.map_flags = BPF_F_NO_PREALLOC,
.btf_key_type_id = 1,
.btf_value_type_id = 3,
};
int fd, btf_fd;
btf_fd = load_btf();
if (btf_fd < 0)
return -1;
attr.btf_fd = btf_fd;
fd = bpf_create_map_xattr(&attr);
close(attr.btf_fd);
if (fd < 0)
printf("Failed to create sk_storage_map\n");
return fd;
}
static char bpf_vlog[UINT_MAX >> 8];
static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
struct bpf_insn *prog, int *map_fds)
{
int *fixup_map_hash_8b = test->fixup_map_hash_8b;
int *fixup_map_hash_48b = test->fixup_map_hash_48b;
int *fixup_map_hash_16b = test->fixup_map_hash_16b;
int *fixup_map_array_48b = test->fixup_map_array_48b;
int *fixup_map_sockmap = test->fixup_map_sockmap;
int *fixup_map_sockhash = test->fixup_map_sockhash;
int *fixup_map_xskmap = test->fixup_map_xskmap;
int *fixup_map_stacktrace = test->fixup_map_stacktrace;
int *fixup_prog1 = test->fixup_prog1;
int *fixup_prog2 = test->fixup_prog2;
int *fixup_map_in_map = test->fixup_map_in_map;
int *fixup_cgroup_storage = test->fixup_cgroup_storage;
int *fixup_percpu_cgroup_storage = test->fixup_percpu_cgroup_storage;
int *fixup_map_spin_lock = test->fixup_map_spin_lock;
int *fixup_map_array_ro = test->fixup_map_array_ro;
int *fixup_map_array_wo = test->fixup_map_array_wo;
int *fixup_map_array_small = test->fixup_map_array_small;
int *fixup_sk_storage_map = test->fixup_sk_storage_map;
int *fixup_map_event_output = test->fixup_map_event_output;
int *fixup_map_reuseport_array = test->fixup_map_reuseport_array;
int *fixup_map_ringbuf = test->fixup_map_ringbuf;
if (test->fill_helper) {
test->fill_insns = calloc(MAX_TEST_INSNS, sizeof(struct bpf_insn));
test->fill_helper(test);
}
/* Allocating HTs with 1 elem is fine here, since we only test
* for verifier and not do a runtime lookup, so the only thing
* that really matters is value size in this case.
*/
if (*fixup_map_hash_8b) {
map_fds[0] = create_map(BPF_MAP_TYPE_HASH, sizeof(long long),
sizeof(long long), 1);
do {
prog[*fixup_map_hash_8b].imm = map_fds[0];
fixup_map_hash_8b++;
} while (*fixup_map_hash_8b);
}
if (*fixup_map_hash_48b) {
map_fds[1] = create_map(BPF_MAP_TYPE_HASH, sizeof(long long),
sizeof(struct test_val), 1);
do {
prog[*fixup_map_hash_48b].imm = map_fds[1];
fixup_map_hash_48b++;
} while (*fixup_map_hash_48b);
}
if (*fixup_map_hash_16b) {
map_fds[2] = create_map(BPF_MAP_TYPE_HASH, sizeof(long long),
sizeof(struct other_val), 1);
do {
prog[*fixup_map_hash_16b].imm = map_fds[2];
fixup_map_hash_16b++;
} while (*fixup_map_hash_16b);
}
if (*fixup_map_array_48b) {
map_fds[3] = create_map(BPF_MAP_TYPE_ARRAY, sizeof(int),
sizeof(struct test_val), 1);
update_map(map_fds[3], 0);
do {
prog[*fixup_map_array_48b].imm = map_fds[3];
fixup_map_array_48b++;
} while (*fixup_map_array_48b);
}
if (*fixup_prog1) {
map_fds[4] = create_prog_array(prog_type, 4, 0, 1, 2);
do {
prog[*fixup_prog1].imm = map_fds[4];
fixup_prog1++;
} while (*fixup_prog1);
}
if (*fixup_prog2) {
map_fds[5] = create_prog_array(prog_type, 8, 7, 1, 2);
do {
prog[*fixup_prog2].imm = map_fds[5];
fixup_prog2++;
} while (*fixup_prog2);
}
if (*fixup_map_in_map) {
map_fds[6] = create_map_in_map();
do {
prog[*fixup_map_in_map].imm = map_fds[6];
fixup_map_in_map++;
} while (*fixup_map_in_map);
}
if (*fixup_cgroup_storage) {
map_fds[7] = create_cgroup_storage(false);
do {
prog[*fixup_cgroup_storage].imm = map_fds[7];
fixup_cgroup_storage++;
} while (*fixup_cgroup_storage);
}
if (*fixup_percpu_cgroup_storage) {
map_fds[8] = create_cgroup_storage(true);
do {
prog[*fixup_percpu_cgroup_storage].imm = map_fds[8];
fixup_percpu_cgroup_storage++;
} while (*fixup_percpu_cgroup_storage);
}
if (*fixup_map_sockmap) {
map_fds[9] = create_map(BPF_MAP_TYPE_SOCKMAP, sizeof(int),
sizeof(int), 1);
do {
prog[*fixup_map_sockmap].imm = map_fds[9];
fixup_map_sockmap++;
} while (*fixup_map_sockmap);
}
if (*fixup_map_sockhash) {
map_fds[10] = create_map(BPF_MAP_TYPE_SOCKHASH, sizeof(int),
sizeof(int), 1);
do {
prog[*fixup_map_sockhash].imm = map_fds[10];
fixup_map_sockhash++;
} while (*fixup_map_sockhash);
}
if (*fixup_map_xskmap) {
map_fds[11] = create_map(BPF_MAP_TYPE_XSKMAP, sizeof(int),
sizeof(int), 1);
do {
prog[*fixup_map_xskmap].imm = map_fds[11];
fixup_map_xskmap++;
} while (*fixup_map_xskmap);
}
if (*fixup_map_stacktrace) {
map_fds[12] = create_map(BPF_MAP_TYPE_STACK_TRACE, sizeof(u32),
sizeof(u64), 1);
do {
prog[*fixup_map_stacktrace].imm = map_fds[12];
fixup_map_stacktrace++;
} while (*fixup_map_stacktrace);
}
if (*fixup_map_spin_lock) {
map_fds[13] = create_map_spin_lock();
do {
prog[*fixup_map_spin_lock].imm = map_fds[13];
fixup_map_spin_lock++;
} while (*fixup_map_spin_lock);
}
if (*fixup_map_array_ro) {
map_fds[14] = __create_map(BPF_MAP_TYPE_ARRAY, sizeof(int),
sizeof(struct test_val), 1,
BPF_F_RDONLY_PROG);
update_map(map_fds[14], 0);
do {
prog[*fixup_map_array_ro].imm = map_fds[14];
fixup_map_array_ro++;
} while (*fixup_map_array_ro);
}
if (*fixup_map_array_wo) {
map_fds[15] = __create_map(BPF_MAP_TYPE_ARRAY, sizeof(int),
sizeof(struct test_val), 1,
BPF_F_WRONLY_PROG);
update_map(map_fds[15], 0);
do {
prog[*fixup_map_array_wo].imm = map_fds[15];
fixup_map_array_wo++;
} while (*fixup_map_array_wo);
}
if (*fixup_map_array_small) {
map_fds[16] = __create_map(BPF_MAP_TYPE_ARRAY, sizeof(int),
1, 1, 0);
update_map(map_fds[16], 0);
do {
prog[*fixup_map_array_small].imm = map_fds[16];
fixup_map_array_small++;
} while (*fixup_map_array_small);
}
if (*fixup_sk_storage_map) {
map_fds[17] = create_sk_storage_map();
do {
prog[*fixup_sk_storage_map].imm = map_fds[17];
fixup_sk_storage_map++;
} while (*fixup_sk_storage_map);
}
if (*fixup_map_event_output) {
map_fds[18] = __create_map(BPF_MAP_TYPE_PERF_EVENT_ARRAY,
sizeof(int), sizeof(int), 1, 0);
do {
prog[*fixup_map_event_output].imm = map_fds[18];
fixup_map_event_output++;
} while (*fixup_map_event_output);
}
if (*fixup_map_reuseport_array) {
map_fds[19] = __create_map(BPF_MAP_TYPE_REUSEPORT_SOCKARRAY,
sizeof(u32), sizeof(u64), 1, 0);
do {
prog[*fixup_map_reuseport_array].imm = map_fds[19];
fixup_map_reuseport_array++;
} while (*fixup_map_reuseport_array);
}
if (*fixup_map_ringbuf) {
map_fds[20] = create_map(BPF_MAP_TYPE_RINGBUF, 0,
0, 4096);
do {
prog[*fixup_map_ringbuf].imm = map_fds[20];
fixup_map_ringbuf++;
} while (*fixup_map_ringbuf);
}
}
struct libcap {
struct __user_cap_header_struct hdr;
struct __user_cap_data_struct data[2];
};
static int set_admin(bool admin)
{
cap_t caps;
/* need CAP_BPF, CAP_NET_ADMIN, CAP_PERFMON to load progs */
const cap_value_t cap_net_admin = CAP_NET_ADMIN;
const cap_value_t cap_sys_admin = CAP_SYS_ADMIN;
struct libcap *cap;
int ret = -1;
caps = cap_get_proc();
if (!caps) {
perror("cap_get_proc");
return -1;
}
cap = (struct libcap *)caps;
if (cap_set_flag(caps, CAP_EFFECTIVE, 1, &cap_sys_admin, CAP_CLEAR)) {
perror("cap_set_flag clear admin");
goto out;
}
if (cap_set_flag(caps, CAP_EFFECTIVE, 1, &cap_net_admin,
admin ? CAP_SET : CAP_CLEAR)) {
perror("cap_set_flag set_or_clear net");
goto out;
}
/* libcap is likely old and simply ignores CAP_BPF and CAP_PERFMON,
* so update effective bits manually
*/
if (admin) {
cap->data[1].effective |= 1 << (38 /* CAP_PERFMON */ - 32);
cap->data[1].effective |= 1 << (39 /* CAP_BPF */ - 32);
} else {
cap->data[1].effective &= ~(1 << (38 - 32));
cap->data[1].effective &= ~(1 << (39 - 32));
}
if (cap_set_proc(caps)) {
perror("cap_set_proc");
goto out;
}
ret = 0;
out:
if (cap_free(caps))
perror("cap_free");
return ret;
}
static int do_prog_test_run(int fd_prog, bool unpriv, uint32_t expected_val,
void *data, size_t size_data)
{
__u8 tmp[TEST_DATA_LEN << 2];
__u32 size_tmp = sizeof(tmp);
uint32_t retval;
int err, saved_errno;
if (unpriv)
set_admin(true);
err = bpf_prog_test_run(fd_prog, 1, data, size_data,
tmp, &size_tmp, &retval, NULL);
saved_errno = errno;
if (unpriv)
set_admin(false);
if (err) {
switch (saved_errno) {
case 524/*ENOTSUPP*/:
printf("Did not run the program (not supported) ");
return 0;
case EPERM:
if (unpriv) {
printf("Did not run the program (no permission) ");
return 0;
}
/* fallthrough; */
default:
printf("FAIL: Unexpected bpf_prog_test_run error (%s) ",
strerror(saved_errno));
return err;
}
}
if (retval != expected_val &&
expected_val != POINTER_VALUE) {
printf("FAIL retval %d != %d ", retval, expected_val);
return 1;
}
return 0;
}
static bool cmp_str_seq(const char *log, const char *exp)
{
char needle[80];
const char *p, *q;
int len;
do {
p = strchr(exp, '\t');
if (!p)
p = exp + strlen(exp);
len = p - exp;
if (len >= sizeof(needle) || !len) {
printf("FAIL\nTestcase bug\n");
return false;
}
strncpy(needle, exp, len);
needle[len] = 0;
q = strstr(log, needle);
if (!q) {
printf("FAIL\nUnexpected verifier log in successful load!\n"
"EXP: %s\nRES:\n", needle);
return false;
}
log = q + len;
exp = p + 1;
} while (*p);
return true;
}
static void do_test_single(struct bpf_test *test, bool unpriv,
int *passes, int *errors)
{
int fd_prog, expected_ret, alignment_prevented_execution;
int prog_len, prog_type = test->prog_type;
struct bpf_insn *prog = test->insns;
struct bpf_load_program_attr attr;
int run_errs, run_successes;
int map_fds[MAX_NR_MAPS];
const char *expected_err;
int saved_errno;
int fixup_skips;
__u32 pflags;
int i, err;
for (i = 0; i < MAX_NR_MAPS; i++)
map_fds[i] = -1;
if (!prog_type)
prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
fixup_skips = skips;
do_test_fixup(test, prog_type, prog, map_fds);
if (test->fill_insns) {
prog = test->fill_insns;
prog_len = test->prog_len;
} else {
prog_len = probe_filter_length(prog);
}
/* If there were some map skips during fixup due to missing bpf
* features, skip this test.
*/
if (fixup_skips != skips)
return;
pflags = BPF_F_TEST_RND_HI32;
if (test->flags & F_LOAD_WITH_STRICT_ALIGNMENT)
pflags |= BPF_F_STRICT_ALIGNMENT;
if (test->flags & F_NEEDS_EFFICIENT_UNALIGNED_ACCESS)
pflags |= BPF_F_ANY_ALIGNMENT;
if (test->flags & ~3)
pflags |= test->flags;
expected_ret = unpriv && test->result_unpriv != UNDEF ?
test->result_unpriv : test->result;
expected_err = unpriv && test->errstr_unpriv ?
test->errstr_unpriv : test->errstr;
memset(&attr, 0, sizeof(attr));
attr.prog_type = prog_type;
attr.expected_attach_type = test->expected_attach_type;
attr.insns = prog;
attr.insns_cnt = prog_len;
attr.license = "GPL";
if (verbose)
attr.log_level = 1;
else if (expected_ret == VERBOSE_ACCEPT)
attr.log_level = 2;
else
attr.log_level = 4;
attr.prog_flags = pflags;
if (prog_type == BPF_PROG_TYPE_TRACING && test->kfunc) {
attr.attach_btf_id = libbpf_find_vmlinux_btf_id(test->kfunc,
attr.expected_attach_type);
if (attr.attach_btf_id < 0) {
printf("FAIL\nFailed to find BTF ID for '%s'!\n",
test->kfunc);
(*errors)++;
return;
}
}
fd_prog = bpf_load_program_xattr(&attr, bpf_vlog, sizeof(bpf_vlog));
saved_errno = errno;
/* BPF_PROG_TYPE_TRACING requires more setup and
* bpf_probe_prog_type won't give correct answer
*/
if (fd_prog < 0 && prog_type != BPF_PROG_TYPE_TRACING &&
!bpf_probe_prog_type(prog_type, 0)) {
printf("SKIP (unsupported program type %d)\n", prog_type);
skips++;
goto close_fds;
}
alignment_prevented_execution = 0;
if (expected_ret == ACCEPT || expected_ret == VERBOSE_ACCEPT) {
if (fd_prog < 0) {
printf("FAIL\nFailed to load prog '%s'!\n",
strerror(saved_errno));
goto fail_log;
}
#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
if (fd_prog >= 0 &&
(test->flags & F_NEEDS_EFFICIENT_UNALIGNED_ACCESS))
alignment_prevented_execution = 1;
#endif
if (expected_ret == VERBOSE_ACCEPT && !cmp_str_seq(bpf_vlog, expected_err)) {
goto fail_log;
}
} else {
if (fd_prog >= 0) {
printf("FAIL\nUnexpected success to load!\n");
goto fail_log;
}
if (!expected_err || !strstr(bpf_vlog, expected_err)) {
printf("FAIL\nUnexpected error message!\n\tEXP: %s\n\tRES: %s\n",
expected_err, bpf_vlog);
goto fail_log;
}
}
if (test->insn_processed) {
uint32_t insn_processed;
char *proc;
proc = strstr(bpf_vlog, "processed ");
insn_processed = atoi(proc + 10);
if (test->insn_processed != insn_processed) {
printf("FAIL\nUnexpected insn_processed %u vs %u\n",
insn_processed, test->insn_processed);
goto fail_log;
}
}
if (verbose)
printf(", verifier log:\n%s", bpf_vlog);
run_errs = 0;
run_successes = 0;
if (!alignment_prevented_execution && fd_prog >= 0) {
uint32_t expected_val;
int i;
if (!test->runs)
test->runs = 1;
for (i = 0; i < test->runs; i++) {
if (unpriv && test->retvals[i].retval_unpriv)
expected_val = test->retvals[i].retval_unpriv;
else
expected_val = test->retvals[i].retval;
err = do_prog_test_run(fd_prog, unpriv, expected_val,
test->retvals[i].data,
sizeof(test->retvals[i].data));
if (err) {
printf("(run %d/%d) ", i + 1, test->runs);
run_errs++;
} else {
run_successes++;
}
}
}
if (!run_errs) {
(*passes)++;
if (run_successes > 1)
printf("%d cases ", run_successes);
printf("OK");
if (alignment_prevented_execution)
printf(" (NOTE: not executed due to unknown alignment)");
printf("\n");
} else {
printf("\n");
goto fail_log;
}
close_fds:
if (test->fill_insns)
free(test->fill_insns);
close(fd_prog);
for (i = 0; i < MAX_NR_MAPS; i++)
close(map_fds[i]);
sched_yield();
return;
fail_log:
(*errors)++;
printf("%s", bpf_vlog);
goto close_fds;
}
static bool is_admin(void)
{
cap_flag_value_t net_priv = CAP_CLEAR;
bool perfmon_priv = false;
bool bpf_priv = false;
struct libcap *cap;
cap_t caps;
#ifdef CAP_IS_SUPPORTED
if (!CAP_IS_SUPPORTED(CAP_SETFCAP)) {
perror("cap_get_flag");
return false;
}
#endif
caps = cap_get_proc();
if (!caps) {
perror("cap_get_proc");
return false;
}
cap = (struct libcap *)caps;
bpf_priv = cap->data[1].effective & (1 << (39/* CAP_BPF */ - 32));
perfmon_priv = cap->data[1].effective & (1 << (38/* CAP_PERFMON */ - 32));
if (cap_get_flag(caps, CAP_NET_ADMIN, CAP_EFFECTIVE, &net_priv))
perror("cap_get_flag NET");
if (cap_free(caps))
perror("cap_free");
return bpf_priv && perfmon_priv && net_priv == CAP_SET;
}
static void get_unpriv_disabled()
{
char buf[2];
FILE *fd;
fd = fopen("/proc/sys/"UNPRIV_SYSCTL, "r");
if (!fd) {
perror("fopen /proc/sys/"UNPRIV_SYSCTL);
unpriv_disabled = true;
return;
}
if (fgets(buf, 2, fd) == buf && atoi(buf))
unpriv_disabled = true;
fclose(fd);
}
static bool test_as_unpriv(struct bpf_test *test)
{
#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
/* Some architectures have strict alignment requirements. In
* that case, the BPF verifier detects if a program has
* unaligned accesses and rejects them. A user can pass
* BPF_F_ANY_ALIGNMENT to a program to override this
* check. That, however, will only work when a privileged user
* loads a program. An unprivileged user loading a program
* with this flag will be rejected prior entering the
* verifier.
*/
if (test->flags & F_NEEDS_EFFICIENT_UNALIGNED_ACCESS)
return false;
#endif
return !test->prog_type ||
test->prog_type == BPF_PROG_TYPE_SOCKET_FILTER ||
test->prog_type == BPF_PROG_TYPE_CGROUP_SKB;
}
static int do_test(bool unpriv, unsigned int from, unsigned int to)
{
int i, passes = 0, errors = 0;
for (i = from; i < to; i++) {
struct bpf_test *test = &tests[i];
/* Program types that are not supported by non-root we
* skip right away.
*/
if (test_as_unpriv(test) && unpriv_disabled) {
printf("#%d/u %s SKIP\n", i, test->descr);
skips++;
} else if (test_as_unpriv(test)) {
if (!unpriv)
set_admin(false);
printf("#%d/u %s ", i, test->descr);
do_test_single(test, true, &passes, &errors);
if (!unpriv)
set_admin(true);
}
if (unpriv) {
printf("#%d/p %s SKIP\n", i, test->descr);
skips++;
} else {
printf("#%d/p %s ", i, test->descr);
do_test_single(test, false, &passes, &errors);
}
}
printf("Summary: %d PASSED, %d SKIPPED, %d FAILED\n", passes,
skips, errors);
return errors ? EXIT_FAILURE : EXIT_SUCCESS;
}
int main(int argc, char **argv)
{
unsigned int from = 0, to = ARRAY_SIZE(tests);
bool unpriv = !is_admin();
int arg = 1;
if (argc > 1 && strcmp(argv[1], "-v") == 0) {
arg++;
verbose = true;
argc--;
}
if (argc == 3) {
unsigned int l = atoi(argv[arg]);
unsigned int u = atoi(argv[arg + 1]);
if (l < to && u < to) {
from = l;
to = u + 1;
}
} else if (argc == 2) {
unsigned int t = atoi(argv[arg]);
if (t < to) {
from = t;
to = t + 1;
}
}
get_unpriv_disabled();
if (unpriv && unpriv_disabled) {
printf("Cannot run as unprivileged user with sysctl %s.\n",
UNPRIV_SYSCTL);
return EXIT_FAILURE;
}
bpf_semi_rand_init();
return do_test(unpriv, from, to);
}