[PATCH v5 3/4] tools/bpf: Add bpf_map_lookup_elem selftest for xskmap

[Jonathan Lemon <jonathan.lemon@gmail.com>]

Check that bpf_map_lookup_elem lookup and structure
access operats correctly.

Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
---
 tools/testing/selftests/bpf/verifier/sock.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/tools/testing/selftests/bpf/verifier/sock.c b/tools/testing/selftests/bpf/verifier/sock.c
index b31cd2cf50d0..9ed192e14f5f 100644
--- a/tools/testing/selftests/bpf/verifier/sock.c
+++ b/tools/testing/selftests/bpf/verifier/sock.c
@@ -498,3 +498,21 @@
 	.result = REJECT,
 	.errstr = "cannot pass map_type 24 into func bpf_map_lookup_elem",
 },
+{
+	"bpf_map_lookup_elem(xskmap, &key); xs->queue_id",
+	.insns = {
+	BPF_ST_MEM(BPF_W, BPF_REG_10, -8, 0),
+	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+	BPF_LD_MAP_FD(BPF_REG_1, 0),
+	BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+	BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
+	BPF_EXIT_INSN(),
+	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, offsetof(struct bpf_xdp_sock, queue_id)),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_map_xskmap = { 3 },
+	.prog_type = BPF_PROG_TYPE_XDP,
+	.result = ACCEPT,
+},
-- 
2.17.1