From: Feng Zhou <zhoufeng.zf@xxxxxxxxxxxxx>
Adding verifier test for accessing u32 pointer argument in
tracing programs.
The test program loads 1nd argument of bpf_fentry_test9 function
which is u32 pointer and checks that verifier allows that.
Co-developed-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
Signed-off-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
Signed-off-by: Feng Zhou <zhoufeng.zf@xxxxxxxxxxxxx>
---
net/bpf/test_run.c | 8 +++++++-
.../testing/selftests/bpf/verifier/btf_ctx_access.c | 13 +++++++++++++
2 files changed, 20 insertions(+), 1 deletion(-)
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index f1652f5fbd2e..68bdfc041a7b 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -541,6 +541,11 @@ int noinline bpf_fentry_test8(struct bpf_fentry_test_t *arg)
return (long)arg->a;
}
+__bpf_kfunc u32 bpf_fentry_test9(u32 *a)
+{
+ return *a;
+}
+
__bpf_kfunc int bpf_modify_return_test(int a, int *b)
{
*b += 1;
@@ -855,7 +860,8 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
bpf_fentry_test5(11, (void *)12, 13, 14, 15) != 65 ||
bpf_fentry_test6(16, (void *)17, 18, 19, (void *)20, 21) != 111 ||
bpf_fentry_test7((struct bpf_fentry_test_t *)0) != 0 ||
- bpf_fentry_test8(&arg) != 0)
+ bpf_fentry_test8(&arg) != 0 ||
+ bpf_fentry_test9(&retval) != 0)
goto out;
break;
case BPF_MODIFY_RETURN:
diff --git a/tools/testing/selftests/bpf/verifier/btf_ctx_access.c b/tools/testing/selftests/bpf/verifier/btf_ctx_access.c
index 6340db6b46dc..0484d3de040d 100644
--- a/tools/testing/selftests/bpf/verifier/btf_ctx_access.c
+++ b/tools/testing/selftests/bpf/verifier/btf_ctx_access.c
@@ -10,3 +10,16 @@
.expected_attach_type = BPF_TRACE_FENTRY,
.kfunc = "bpf_modify_return_test",
},
+
+{
+ "btf_ctx_access u32 pointer accept",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 0), /* load 1nd argument value (u32 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_fentry_test9",
+},
--
2.20.1
