[PATCH net-next 2/3] samples: bpf: add a verifier test and summary line

From: Alexei Starovoitov
Date: Tue Oct 28 2014 - 18:13:23 EST


- add a test specifically targeting verifier state pruning.
It checks state propagation between registers, storing that
state into stack and state pruning algorithm recognizing
equivalent stack and register states.

- add summary line to spot failures easier

Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxxxx>
---
samples/bpf/test_verifier.c | 46 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 45 insertions(+), 1 deletion(-)

diff --git a/samples/bpf/test_verifier.c b/samples/bpf/test_verifier.c
index eb4bec0ad8af..63402742345e 100644
--- a/samples/bpf/test_verifier.c
+++ b/samples/bpf/test_verifier.c
@@ -602,6 +602,45 @@ static struct bpf_test tests[] = {
},
.result = ACCEPT,
},
+ {
+ "jump test 5",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+ BPF_MOV64_REG(BPF_REG_3, BPF_REG_2),
+ BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
+ BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, -8),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 2),
+ BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, -8),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
+ BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, -8),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 2),
+ BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, -8),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
+ BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, -8),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 2),
+ BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, -8),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
+ BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, -8),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 2),
+ BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, -8),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2),
+ BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, -8),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 2),
+ BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, -8),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ },
};

static int probe_filter_length(struct bpf_insn *fp)
@@ -630,7 +669,7 @@ static int create_map(void)

static int test(void)
{
- int prog_fd, i;
+ int prog_fd, i, pass_cnt = 0, err_cnt = 0;

for (i = 0; i < ARRAY_SIZE(tests); i++) {
struct bpf_insn *prog = tests[i].insns;
@@ -657,21 +696,25 @@ static int test(void)
printf("FAIL\nfailed to load prog '%s'\n",
strerror(errno));
printf("%s", bpf_log_buf);
+ err_cnt++;
goto fail;
}
} else {
if (prog_fd >= 0) {
printf("FAIL\nunexpected success to load\n");
printf("%s", bpf_log_buf);
+ err_cnt++;
goto fail;
}
if (strstr(bpf_log_buf, tests[i].errstr) == 0) {
printf("FAIL\nunexpected error message: %s",
bpf_log_buf);
+ err_cnt++;
goto fail;
}
}

+ pass_cnt++;
printf("OK\n");
fail:
if (map_fd >= 0)
@@ -679,6 +722,7 @@ fail:
close(prog_fd);

}
+ printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, err_cnt);

return 0;
}
--
1.7.9.5

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