bpf: add test case for ld_abs and helper changing pkt data
Add a test that i) uses LD_ABS, ii) zeroing R6 before call, iii) calls
a helper that triggers reload of cached skb data, iv) uses LD_ABS again.
It's added for test_bpf in order to do runtime testing after JITing as
well as test_verifier to test that the sequence is allowed.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 3c64f30..b03ecfd 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -6117,6 +6117,30 @@ static struct bpf_test tests[] = {
.result = ACCEPT,
},
{
+ "ld_abs: tests on r6 and skb data reload helper",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_LD_ABS(BPF_B, 0),
+ BPF_LD_ABS(BPF_H, 0),
+ BPF_LD_ABS(BPF_W, 0),
+ BPF_MOV64_REG(BPF_REG_7, BPF_REG_6),
+ BPF_MOV64_IMM(BPF_REG_6, 0),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
+ BPF_MOV64_IMM(BPF_REG_2, 1),
+ BPF_MOV64_IMM(BPF_REG_3, 2),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_skb_vlan_push),
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_7),
+ BPF_LD_ABS(BPF_B, 0),
+ BPF_LD_ABS(BPF_H, 0),
+ BPF_LD_ABS(BPF_W, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 42),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = ACCEPT,
+ },
+ {
"ld_ind: check calling conv, r1",
.insns = {
BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),