linux/tools/testing
Eduard Zingerman 933ff53191 selftests/bpf: specify expected instructions in test_verifier tests
Allows to specify expected and unexpected instruction sequences in
test_verifier test cases. The instructions are requested from kernel
after BPF program loading, thus allowing to check some of the
transformations applied by BPF verifier.

- `expected_insn` field specifies a sequence of instructions expected
  to be found in the program;
- `unexpected_insn` field specifies a sequence of instructions that
  are not expected to be found in the program;
- `INSN_OFF_MASK` and `INSN_IMM_MASK` values could be used to mask
  `off` and `imm` fields.
- `SKIP_INSNS` could be used to specify that some instructions in the
  (un)expected pattern are not important (behavior similar to usage of
  `\t` in `errstr` field).

The intended usage is as follows:

  {
	"inline simple bpf_loop call",
	.insns = {
	/* main */
	BPF_ALU64_IMM(BPF_MOV, BPF_REG_1, 1),
	BPF_RAW_INSN(BPF_LD | BPF_IMM | BPF_DW, BPF_REG_2,
			BPF_PSEUDO_FUNC, 0, 6),
    ...
	BPF_EXIT_INSN(),
	/* callback */
	BPF_ALU64_IMM(BPF_MOV, BPF_REG_0, 1),
	BPF_EXIT_INSN(),
	},
	.expected_insns = {
	BPF_ALU64_IMM(BPF_MOV, BPF_REG_1, 1),
	SKIP_INSNS(),
	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_CALL, 8, 1)
	},
	.unexpected_insns = {
	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0,
			INSN_OFF_MASK, INSN_IMM_MASK),
	},
	.prog_type = BPF_PROG_TYPE_TRACEPOINT,
	.result = ACCEPT,
	.runs = 0,
  },

Here it is expected that move of 1 to register 1 would remain in place
and helper function call instruction would be replaced by a relative
call instruction.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/r/20220620235344.569325-2-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-20 17:40:51 -07:00
..
crypto/chacha20-s390 crypto: s390 - add crypto library interface for ChaCha20 2022-05-13 17:24:49 +08:00
cxl cxl/port: Reuse 'struct cxl_hdm' context for hdm init 2022-05-19 08:50:42 -07:00
fault-injection
ktest
kunit kunit: tool: Use qemu-system-i386 for i386 runs 2022-05-18 17:03:54 -06:00
memblock memblock tests: remove completed TODO item 2022-05-09 13:10:58 +03:00
nvdimm dax: introduce DAX_RECOVERY_WRITE dax access mode 2022-05-16 13:35:56 -07:00
radix-tree tools: Add kmem_cache_alloc_lru() 2022-04-22 14:24:28 -04:00
scatterlist
selftests selftests/bpf: specify expected instructions in test_verifier tests 2022-06-20 17:40:51 -07:00
vsock af_vsock: SOCK_SEQPACKET broken buffer test 2022-03-18 15:13:19 +00:00