Adding verifier test for accessing union argument in tracing programs.
The test program loads 1st argument of bpf_fentry_test11 function
which is union and checks that verifier allows that.
cd tools/testing/selftests/bpf
./test_progs -t verifier_btf_ctx
501/7 verifier_btf_ctx_access/btf_ctx_access union arg accept:OK
501 verifier_btf_ctx_access:OK
Summary: 1/7 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Leon Hwang <leon.hwang@xxxxxxxxx>
---
net/bpf/test_run.c | 14 +++++++++++++-
.../selftests/bpf/progs/verifier_btf_ctx_access.c | 12 ++++++++++++
2 files changed, 25 insertions(+), 1 deletion(-)
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 4a862d6053861..c65d468fd6012 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -574,6 +574,16 @@ noinline int bpf_fentry_test10(const void *a)
return (long)a;
}
+typedef union {
+ void *arg0;
+ int *arg1;
+} union_test_t;
+
+noinline int bpf_fentry_test11(union_test_t t)
+{
+ return (int)(long)t.arg0;
+}
+
noinline void bpf_fentry_test_sinfo(struct skb_shared_info *sinfo)
{
}
@@ -688,6 +698,7 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
struct bpf_fentry_test_t arg = {};
u16 side_effect = 0, ret = 0;
int b = 2, err = -EFAULT;
+ union_test_t utt = {};
u32 retval = 0;
if (kattr->test.flags || kattr->test.cpu || kattr->test.batch_size)
@@ -705,7 +716,8 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
bpf_fentry_test7((struct bpf_fentry_test_t *)0) != 0 ||
bpf_fentry_test8(&arg) != 0 ||
bpf_fentry_test9(&retval) != 0 ||
- bpf_fentry_test10((void *)0) != 0)
+ bpf_fentry_test10((void *)0) != 0 ||
+ bpf_fentry_test11(utt) != 0)
goto out;
break;
case BPF_MODIFY_RETURN:
diff --git a/tools/testing/selftests/bpf/progs/verifier_btf_ctx_access.c b/tools/testing/selftests/bpf/progs/verifier_btf_ctx_access.c
index 03942cec07e56..ff379836b5f00 100644
--- a/tools/testing/selftests/bpf/progs/verifier_btf_ctx_access.c
+++ b/tools/testing/selftests/bpf/progs/verifier_btf_ctx_access.c
@@ -77,4 +77,16 @@ __naked void ctx_access_const_void_pointer_accept(void)
" ::: __clobber_all);
}
+SEC("fentry/bpf_fentry_test11")
+__description("btf_ctx_access union arg accept")
+__success __retval(0)
+__naked void ctx_access_union_arg_accept(void)
+{
+ asm volatile (" \
+ r2 = *(u64 *)(r1 + 0); /* load 1st argument value (union) */\
+ r0 = 0; \
+ exit; \
+" ::: __clobber_all);
+}
+
char _license[] SEC("license") = "GPL";
--
2.50.1
