[PATCH bpf v3 2/3] selftests/bpf: Fix cgroup bpf tests broken by bpf_set_retval validation

[Xu Kuohai]

From: Xu Kuohai <xukuohai@xxxxxxxxxx>

Add explicit return value checks for cgroup bpf progs rejected by the
bpf_set_retval validation.

Signed-off-by: Xu Kuohai <xukuohai@xxxxxxxxxx>
---
 .../selftests/bpf/progs/cgroup_getset_retval_hooks.c        | 6 +++++-
 tools/testing/selftests/bpf/progs/sk_bypass_prot_mem.c      | 2 ++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/progs/cgroup_getset_retval_hooks.c b/tools/testing/selftests/bpf/progs/cgroup_getset_retval_hooks.c
index 13dfb4bbfd28..c0bfa2d12dc7 100644
--- a/tools/testing/selftests/bpf/progs/cgroup_getset_retval_hooks.c
+++ b/tools/testing/selftests/bpf/progs/cgroup_getset_retval_hooks.c
@@ -2,12 +2,16 @@
 
 #include <linux/bpf.h>
 #include <bpf/bpf_helpers.h>
+#include <errno.h>
+#include "err.h"
 
 #define BPF_RETVAL_HOOK(name, section, ctx, expected_err) \
 	__attribute__((__section__("?" section))) \
 	int name(struct ctx *_ctx) \
 	{ \
-		bpf_set_retval(bpf_get_retval()); \
+		int val = bpf_get_retval(); \
+		set_if_not_errno_or_zero(val, -EFAULT); \
+		bpf_set_retval(val); \
 		return 1; \
 	}
 
diff --git a/tools/testing/selftests/bpf/progs/sk_bypass_prot_mem.c b/tools/testing/selftests/bpf/progs/sk_bypass_prot_mem.c
index 09a00d11ffcc..bae5283fca6b 100644
--- a/tools/testing/selftests/bpf/progs/sk_bypass_prot_mem.c
+++ b/tools/testing/selftests/bpf/progs/sk_bypass_prot_mem.c
@@ -5,6 +5,7 @@
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
 #include <errno.h>
+#include "err.h"
 
 extern int tcp_memory_per_cpu_fw_alloc __ksym;
 extern int udp_memory_per_cpu_fw_alloc __ksym;
@@ -97,6 +98,7 @@ int sock_create(struct bpf_sock *ctx)
 	return 1;
 
 err:
+	set_if_not_errno_or_zero(err, -EFAULT);
 	bpf_set_retval(err);
 	return 0;
 }
-- 
2.43.0