From 35cc9d622e8cd45029a1656ab2c6817538bc4180 Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Fri, 14 Oct 2022 17:24:43 -0700 Subject: selftests/bpf: Add reproducer for decl_tag in func_proto return type It should trigger a WARN_ON_ONCE in btf_type_id_size. btf_func_proto_check kernel/bpf/btf.c:4447 [inline] btf_check_all_types kernel/bpf/btf.c:4723 [inline] btf_parse_type_sec kernel/bpf/btf.c:4752 [inline] btf_parse kernel/bpf/btf.c:5026 [inline] btf_new_fd+0x1926/0x1e70 kernel/bpf/btf.c:6892 bpf_btf_load kernel/bpf/syscall.c:4324 [inline] __sys_bpf+0xb7d/0x4cf0 kernel/bpf/syscall.c:5010 __do_sys_bpf kernel/bpf/syscall.c:5069 [inline] __se_sys_bpf kernel/bpf/syscall.c:5067 [inline] __x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:5067 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Cc: Yonghong Song Cc: Martin KaFai Lau Signed-off-by: Stanislav Fomichev Acked-by: Yonghong Song Link: https://lore.kernel.org/r/20221015002444.2680969-1-sdf@google.com Signed-off-by: Martin KaFai Lau --- tools/testing/selftests/bpf/prog_tests/btf.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'tools/testing/selftests/bpf/prog_tests') diff --git a/tools/testing/selftests/bpf/prog_tests/btf.c b/tools/testing/selftests/bpf/prog_tests/btf.c index 127b8caa3dc1..24dd6214394e 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf.c +++ b/tools/testing/selftests/bpf/prog_tests/btf.c @@ -3935,6 +3935,19 @@ static struct btf_raw_test raw_tests[] = { .btf_load_err = true, .err_str = "Invalid type_id", }, +{ + .descr = "decl_tag test #16, func proto, return type", + .raw_types = { + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ + BTF_VAR_ENC(NAME_TBD, 1, 0), /* [2] */ + BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_DECL_TAG, 0, 0), 2), (-1), /* [3] */ + BTF_FUNC_PROTO_ENC(3, 0), /* [4] */ + BTF_END_RAW, + }, + BTF_STR_SEC("\0local\0tag1"), + .btf_load_err = true, + .err_str = "Invalid return type", +}, { .descr = "type_tag test #1", .raw_types = { -- cgit v1.2.3 From 9cd094829dae949a755c18533479c20e74415ab2 Mon Sep 17 00:00:00 2001 From: Alban Crequy Date: Thu, 10 Nov 2022 09:56:14 +0100 Subject: selftests: bpf: Add a test when bpf_probe_read_kernel_str() returns EFAULT This commit tests previous fix of bpf_probe_read_kernel_str(). The BPF helper bpf_probe_read_kernel_str should return -EFAULT when given a bad source pointer and the target buffer should only be modified to make the string NULL terminated. bpf_probe_read_kernel_str() was previously inserting a NULL before the beginning of the dst buffer. This test should ensure that the implementation stays correct for now on. Without the fix, this test will fail as follows: $ cd tools/testing/selftests/bpf $ make $ sudo ./test_progs --name=varlen ... test_varlen:FAIL:check got 0 != exp 66 Signed-off-by: Alban Crequy Signed-off-by: Francis Laniel Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20221110085614.111213-3-albancrequy@linux.microsoft.com Changes v1 to v2: - add ack tag - fix my email - rebase on bpf tree and tag for bpf tree --- tools/testing/selftests/bpf/prog_tests/varlen.c | 7 +++++++ tools/testing/selftests/bpf/progs/test_varlen.c | 5 +++++ 2 files changed, 12 insertions(+) (limited to 'tools/testing/selftests/bpf/prog_tests') diff --git a/tools/testing/selftests/bpf/prog_tests/varlen.c b/tools/testing/selftests/bpf/prog_tests/varlen.c index dd324b4933db..4d7056f8f177 100644 --- a/tools/testing/selftests/bpf/prog_tests/varlen.c +++ b/tools/testing/selftests/bpf/prog_tests/varlen.c @@ -63,6 +63,13 @@ void test_varlen(void) CHECK_VAL(data->total4, size1 + size2); CHECK(memcmp(data->payload4, exp_str, size1 + size2), "content_check", "doesn't match!\n"); + + CHECK_VAL(bss->ret_bad_read, -EFAULT); + CHECK_VAL(data->payload_bad[0], 0x42); + CHECK_VAL(data->payload_bad[1], 0x42); + CHECK_VAL(data->payload_bad[2], 0); + CHECK_VAL(data->payload_bad[3], 0x42); + CHECK_VAL(data->payload_bad[4], 0x42); cleanup: test_varlen__destroy(skel); } diff --git a/tools/testing/selftests/bpf/progs/test_varlen.c b/tools/testing/selftests/bpf/progs/test_varlen.c index 3987ff174f1f..20eb7d422c41 100644 --- a/tools/testing/selftests/bpf/progs/test_varlen.c +++ b/tools/testing/selftests/bpf/progs/test_varlen.c @@ -19,6 +19,7 @@ __u64 payload1_len1 = 0; __u64 payload1_len2 = 0; __u64 total1 = 0; char payload1[MAX_LEN + MAX_LEN] = {}; +__u64 ret_bad_read = 0; /* .data */ int payload2_len1 = -1; @@ -36,6 +37,8 @@ int payload4_len2 = -1; int total4= -1; char payload4[MAX_LEN + MAX_LEN] = { 1 }; +char payload_bad[5] = { 0x42, 0x42, 0x42, 0x42, 0x42 }; + SEC("raw_tp/sys_enter") int handler64_unsigned(void *regs) { @@ -61,6 +64,8 @@ int handler64_unsigned(void *regs) total1 = payload - (void *)payload1; + ret_bad_read = bpf_probe_read_kernel_str(payload_bad + 2, 1, (void *) -1); + return 0; } -- cgit v1.2.3