Add a gotox regression test with two one-entry INSN_ARRAY maps. CFG can model a map whose target stays in the main subprog, while the verified path can load a different map whose target is the first instruction of another subprog.
That second target is outside the subprog that contains this gotox instruction, so program load must be rejected with -EINVAL. Signed-off-by: Nuoqi Gui <[email protected]> --- tools/testing/selftests/bpf/prog_tests/bpf_gotox.c | 73 ++++++++++++++++++++++ 1 file changed, 73 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_gotox.c b/tools/testing/selftests/bpf/prog_tests/bpf_gotox.c index 73dc63882b7d..5252ca09689c 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_gotox.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_gotox.c @@ -255,6 +255,30 @@ static int create_jt_map(__u32 max_entries) key_size, value_size, max_entries, NULL); } +static int create_jt_map_with_target(__u32 target) +{ + struct bpf_insn_array_value val = { .orig_off = target }; + __u32 key = 0; + int map_fd; + + map_fd = create_jt_map(1); + if (!ASSERT_GE(map_fd, 0, "create_jt_map")) + return -1; + + if (!ASSERT_EQ(bpf_map_update_elem(map_fd, &key, &val, 0), + 0, "bpf_map_update_elem")) { + close(map_fd); + return -1; + } + + if (!ASSERT_EQ(bpf_map_freeze(map_fd), 0, "bpf_map_freeze")) { + close(map_fd); + return -1; + } + + return map_fd; +} + static int prog_load(struct bpf_insn *insns, __u32 insn_cnt) { return bpf_prog_load(BPF_PROG_TYPE_RAW_TRACEPOINT, NULL, "GPL", insns, insn_cnt, NULL); @@ -393,6 +417,52 @@ reject_offsets(struct bpf_insn *insns, __u32 insn_cnt, int off1, int off2, int o close(prog_fd); } +static void +check_cross_subprog_gotox_target(struct bpf_gotox *skel __always_unused) +{ + struct bpf_insn insns[] = { + /* main subprog [0,14) */ + BPF_MOV64_REG(BPF_REG_6, BPF_REG_1), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_CALL, 0, 12), + BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6, 0), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_7, 0, 4), + BPF_LD_IMM64_RAW(BPF_REG_2, BPF_PSEUDO_MAP_VALUE, 0), + BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, 0), + BPF_JMP_A(3), + BPF_LD_IMM64_RAW(BPF_REG_2, BPF_PSEUDO_MAP_VALUE, 0), + BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_2, 0), + BPF_RAW_INSN(BPF_JMP | BPF_JA | BPF_X, BPF_REG_2, 0, 0, 0), + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_EXIT_INSN(), + + /* static subprog [14,16) */ + BPF_MOV64_IMM(BPF_REG_0, 42), + BPF_EXIT_INSN(), + }; + int good_fd, bad_fd, prog_fd; + + good_fd = create_jt_map_with_target(12); + if (!ASSERT_GE(good_fd, 0, "create_good_jt_map")) + return; + + bad_fd = create_jt_map_with_target(14); + if (!ASSERT_GE(bad_fd, 0, "create_bad_jt_map")) { + close(good_fd); + return; + } + + insns[4].imm = bad_fd; + insns[8].imm = good_fd; + + prog_fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL", + insns, ARRAY_SIZE(insns), NULL); + if (!ASSERT_EQ(prog_fd, -EINVAL, "cross_subprog_gotox_prog_load")) + close(prog_fd); + + close(bad_fd); + close(good_fd); +} + /* * Verify a bit more complex programs which include indirect jumps * and with jump tables loaded with a non-zero offset @@ -538,6 +608,9 @@ void test_bpf_gotox(void) if (test__start_subtest("check-ldimm64-off-gotox")) __subtest(skel, check_ldimm64_off_gotox); + if (test__start_subtest("check-cross-subprog-gotox-target")) + check_cross_subprog_gotox_target(skel); + if (test__start_subtest("check-ldimm64-off-gotox-llvm")) __subtest(skel, check_ldimm64_off_gotox_llvm); -- 2.34.1
