From: Jiri Olsa <jolsa@redhat.com>
Date: Wed, 8 Dec 2021 20:32:42 +0100
Subject: selftests/bpf: Add test to access int ptr argument in tracing program
Patch-mainline: v5.17-rc1
Git-commit: 2b070c2bc885977ca8fe76ba8f6b9d73d8d20e39
References: jsc#PED-1368

Adding verifier test for accessing int pointer argument in
tracing programs.

The test program loads 2nd argument of bpf_modify_return_test
function which is int pointer and checks that verifier allows
that.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211208193245.172141-3-jolsa@kernel.org
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
 tools/testing/selftests/bpf/verifier/btf_ctx_access.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/verifier/btf_ctx_access.c

--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/btf_ctx_access.c
@@ -0,0 +1,12 @@
+{
+	"btf_ctx_access accept",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 8),	/* load 2nd argument value (int pointer) */
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_TRACING,
+	.expected_attach_type = BPF_TRACE_FENTRY,
+	.kfunc = "bpf_modify_return_test",
+},