selftests/bpf: Add test to exercise typedef walking

Add new bpf_fentry_test_sinfo with skb_shared_info argument and try to
access frags.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230626212522.2414485-2-sdf@google.com

diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 2321bd2..63b11f7 100644 (file)
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -555,6 +555,10 @@ __bpf_kfunc u32 bpf_fentry_test9(u32 *a)
        return *a;
 }
 
+void noinline bpf_fentry_test_sinfo(struct skb_shared_info *sinfo)
+{
+}
+
 __bpf_kfunc int bpf_modify_return_test(int a, int *b)
 {
        *b += 1;

diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c
index 070a138..c375e59 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/verifier.c
+++ b/tools/testing/selftests/bpf/prog_tests/verifier.c
@@ -58,6 +58,7 @@
 #include "verifier_stack_ptr.skel.h"
 #include "verifier_subprog_precision.skel.h"
 #include "verifier_subreg.skel.h"
+#include "verifier_typedef.skel.h"
 #include "verifier_uninit.skel.h"
 #include "verifier_unpriv.skel.h"
 #include "verifier_unpriv_perf.skel.h"
@@ -159,6 +160,7 @@ void test_verifier_spin_lock(void)            { RUN(verifier_spin_lock); }
 void test_verifier_stack_ptr(void)            { RUN(verifier_stack_ptr); }
 void test_verifier_subprog_precision(void)    { RUN(verifier_subprog_precision); }
 void test_verifier_subreg(void)               { RUN(verifier_subreg); }
+void test_verifier_typedef(void)              { RUN(verifier_typedef); }
 void test_verifier_uninit(void)               { RUN(verifier_uninit); }
 void test_verifier_unpriv(void)               { RUN(verifier_unpriv); }
 void test_verifier_unpriv_perf(void)          { RUN(verifier_unpriv_perf); }

diff --git a/tools/testing/selftests/bpf/progs/verifier_typedef.c b/tools/testing/selftests/bpf/progs/verifier_typedef.c
new file mode 100644 (file)
index 0000000..08481cf
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/verifier_typedef.c
@@ -0,0 +1,23 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+SEC("fentry/bpf_fentry_test_sinfo")
+__description("typedef: resolve")
+__success __retval(0)
+__naked void resolve_typedef(void)
+{
+       asm volatile ("                                 \
+       r1 = *(u64 *)(r1 +0);                           \
+       r2 = *(u64 *)(r1 +%[frags_offs]);               \
+       r0 = 0;                                         \
+       exit;                                           \
+"      :
+       : __imm_const(frags_offs,
+                     offsetof(struct skb_shared_info, frags))
+       : __clobber_all);
+}
+
+char _license[] SEC("license") = "GPL";