From 4eb93fea59199c1aa6a6f837e90bdd597804cdcc Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Thu, 6 Feb 2025 17:48:09 -0800 Subject: selftests/bpf: add test for LDX/STX/ST relocations over array field Add a simple repro for the issue of miscalculating LDX/STX/ST CO-RE relocation size adjustment when the CO-RE relocation target type is an ARRAY. We need to make sure that compiler generates LDX/STX/ST instruction with CO-RE relocation against entire ARRAY type, not ARRAY's element. With the code pattern in selftest, we get this: 59: 61 71 00 00 00 00 00 00 w1 = *(u32 *)(r7 + 0x0) 00000000000001d8: CO-RE [5] struct core_reloc_arrays::a (0:0) Where offset of `int a[5]` is embedded (through CO-RE relocation) into memory load instruction itself. Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20250207014809.1573841-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/prog_tests/core_reloc.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'tools/testing/selftests/bpf/prog_tests') diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c index e10ea92c3fe2..08963c82f30b 100644 --- a/tools/testing/selftests/bpf/prog_tests/core_reloc.c +++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c @@ -85,11 +85,11 @@ static int duration = 0; #define NESTING_ERR_CASE(name) { \ NESTING_CASE_COMMON(name), \ .fails = true, \ - .run_btfgen_fails = true, \ + .run_btfgen_fails = true, \ } #define ARRAYS_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \ - .a = { [2] = 1 }, \ + .a = { [2] = 1, [3] = 11 }, \ .b = { [1] = { [2] = { [3] = 2 } } }, \ .c = { [1] = { .c = 3 } }, \ .d = { [0] = { [0] = { .d = 4 } } }, \ @@ -108,6 +108,7 @@ static int duration = 0; .input_len = sizeof(struct core_reloc_##name), \ .output = STRUCT_TO_CHAR_PTR(core_reloc_arrays_output) { \ .a2 = 1, \ + .a3 = 12, \ .b123 = 2, \ .c1c = 3, \ .d00d = 4, \ @@ -602,6 +603,7 @@ static const struct core_reloc_test_case test_cases[] = { ARRAYS_ERR_CASE(arrays___err_non_array), ARRAYS_ERR_CASE(arrays___err_wrong_val_type), ARRAYS_ERR_CASE(arrays___err_bad_zero_sz_arr), + ARRAYS_ERR_CASE(arrays___err_bad_signed_arr_elem_sz), /* enum/ptr/int handling scenarios */ PRIMITIVES_CASE(primitives), -- cgit v1.2.3