This patch adds a test case, as shown below, for the verifier error
"more than one arg with ref_obj_id".
0: (b7) r2 = 20
1: (b7) r3 = 0
2: (18) r1 = 0xffff92cee3cbc600
4: (85) call bpf_ringbuf_reserve#131
5: (55) if r0 == 0x0 goto pc+3
6: (bf) r1 = r0
7: (bf) r2 = r0
8: (85) call bpf_tcp_raw_gen_syncookie_ipv4#204
9: (95) exit
This error is currently incorrectly reported as a verifier bug, with a
warning. The next patch in this series will address that.
Signed-off-by: Paul Chaignon <paul.chaignon@xxxxxxxxx>
---
tools/testing/selftests/bpf/verifier/calls.c | 24 ++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/tools/testing/selftests/bpf/verifier/calls.c b/tools/testing/selftests/bpf/verifier/calls.c
index 18596ae0b0c1..f3492efc8834 100644
--- a/tools/testing/selftests/bpf/verifier/calls.c
+++ b/tools/testing/selftests/bpf/verifier/calls.c
@@ -2409,3 +2409,27 @@
.errstr_unpriv = "",
.prog_type = BPF_PROG_TYPE_CGROUP_SKB,
},
+{
+ "calls: several args with ref_obj_id",
+ .insns = {
+ /* Reserve at least sizeof(struct iphdr) bytes in the ring buffer.
+ * With a smaller size, the verifier would reject the call to
+ * bpf_tcp_raw_gen_syncookie_ipv4 before we can reach the
+ * ref_obj_id error.
+ */
+ BPF_MOV64_IMM(BPF_REG_2, 20),
+ BPF_MOV64_IMM(BPF_REG_3, 0),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_ringbuf_reserve),
+ /* if r0 == 0 goto <exit> */
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tcp_raw_gen_syncookie_ipv4),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_ringbuf = { 2 },
+ .result = REJECT,
+ .errstr = "more than one arg with ref_obj_id",
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+},
--
2.43.0
