selftests/bpf: Negative test case for tail call map

This patch adds a negative test case for the following verifier error.

    expected prog array map for tail call

Acked-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/aGu0i1X_jII-3aFa@mail.gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c
index c9da067411046c1069062f91eeef7d0ece140a37..77ec95d4ffaae9d0df0b7317870b6e42942b71be 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/verifier.c
+++ b/tools/testing/selftests/bpf/prog_tests/verifier.c
@@ -85,6 +85,7 @@
 #include "verifier_store_release.skel.h"
 #include "verifier_subprog_precision.skel.h"
 #include "verifier_subreg.skel.h"
+#include "verifier_tailcall.skel.h"
 #include "verifier_tailcall_jit.skel.h"
 #include "verifier_typedef.skel.h"
 #include "verifier_uninit.skel.h"
@@ -219,6 +220,7 @@ void test_verifier_stack_ptr(void)            { RUN(verifier_stack_ptr); }
 void test_verifier_store_release(void)        { RUN(verifier_store_release); }
 void test_verifier_subprog_precision(void)    { RUN(verifier_subprog_precision); }
 void test_verifier_subreg(void)               { RUN(verifier_subreg); }
+void test_verifier_tailcall(void)             { RUN(verifier_tailcall); }
 void test_verifier_tailcall_jit(void)         { RUN(verifier_tailcall_jit); }
 void test_verifier_typedef(void)              { RUN(verifier_typedef); }
 void test_verifier_uninit(void)               { RUN(verifier_uninit); }

diff --git a/tools/testing/selftests/bpf/progs/verifier_tailcall.c b/tools/testing/selftests/bpf/progs/verifier_tailcall.c
new file mode 100644 (file)
index 0000000..b4acce6
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/verifier_tailcall.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+struct {
+       __uint(type, BPF_MAP_TYPE_ARRAY);
+       __uint(max_entries, 1);
+       __type(key, __u32);
+       __type(value, __u32);
+} map_array SEC(".maps");
+
+SEC("socket")
+__description("invalid map type for tail call")
+__failure __msg("expected prog array map for tail call")
+__failure_unpriv
+__naked void invalid_map_for_tail_call(void)
+{
+       asm volatile ("                 \
+       r2 = %[map_array] ll;   \
+       r3 = 0;                         \
+       call %[bpf_tail_call];          \
+       exit;                           \
+"      :
+       : __imm(bpf_tail_call),
+         __imm_addr(map_array)
+       : __clobber_all);
+}
+
+char _license[] SEC("license") = "GPL";