diff options
7 files changed, 85 insertions, 9 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index c9f90bfd2f0d..a2cc7313763a 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -3108,6 +3108,21 @@ static bool str_is_empty(const char *s) return !s || !s[0]; } +static bool is_flex_arr(const struct btf *btf, + const struct bpf_core_accessor *acc, + const struct btf_array *arr) +{ + const struct btf_type *t; + + /* not a flexible array, if not inside a struct or has non-zero size */ + if (!acc->name || arr->nelems > 0) + return false; + + /* has to be the last member of enclosing struct */ + t = btf__type_by_id(btf, acc->type_id); + return acc->idx == btf_vlen(t) - 1; +} + /* * Turn bpf_field_reloc into a low- and high-level spec representation, * validating correctness along the way, as well as calculating resulting @@ -3145,6 +3160,7 @@ static int bpf_core_spec_parse(const struct btf *btf, struct bpf_core_spec *spec) { int access_idx, parsed_len, i; + struct bpf_core_accessor *acc; const struct btf_type *t; const char *name; __u32 id; @@ -3192,6 +3208,7 @@ static int bpf_core_spec_parse(const struct btf *btf, return -EINVAL; access_idx = spec->raw_spec[i]; + acc = &spec->spec[spec->len]; if (btf_is_composite(t)) { const struct btf_member *m; @@ -3209,18 +3226,23 @@ static int bpf_core_spec_parse(const struct btf *btf, if (str_is_empty(name)) return -EINVAL; - spec->spec[spec->len].type_id = id; - spec->spec[spec->len].idx = access_idx; - spec->spec[spec->len].name = name; + acc->type_id = id; + acc->idx = access_idx; + acc->name = name; spec->len++; } id = m->type; } else if (btf_is_array(t)) { const struct btf_array *a = btf_array(t); + bool flex; t = skip_mods_and_typedefs(btf, a->type, &id); - if (!t || access_idx >= a->nelems) + if (!t) + return -EINVAL; + + flex = is_flex_arr(btf, acc - 1, a); + if (!flex && access_idx >= a->nelems) return -EINVAL; spec->spec[spec->len].type_id = id; @@ -3525,12 +3547,14 @@ static int bpf_core_spec_match(struct bpf_core_spec *local_spec, */ if (i > 0) { const struct btf_array *a; + bool flex; if (!btf_is_array(targ_type)) return 0; a = btf_array(targ_type); - if (local_acc->idx >= a->nelems) + flex = is_flex_arr(targ_btf, targ_acc - 1, a); + if (!flex && local_acc->idx >= a->nelems) return 0; if (!skip_mods_and_typedefs(targ_btf, a->type, &targ_id)) diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c index 05fe85281ff7..31e177adbdf1 100644 --- a/tools/testing/selftests/bpf/prog_tests/core_reloc.c +++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c @@ -74,6 +74,7 @@ .b123 = 2, \ .c1c = 3, \ .d00d = 4, \ + .f10c = 0, \ }, \ .output_len = sizeof(struct core_reloc_arrays_output) \ } @@ -308,12 +309,15 @@ static struct core_reloc_test_case test_cases[] = { ARRAYS_CASE(arrays), ARRAYS_CASE(arrays___diff_arr_dim), ARRAYS_CASE(arrays___diff_arr_val_sz), + ARRAYS_CASE(arrays___equiv_zero_sz_arr), + ARRAYS_CASE(arrays___fixed_arr), ARRAYS_ERR_CASE(arrays___err_too_small), ARRAYS_ERR_CASE(arrays___err_too_shallow), ARRAYS_ERR_CASE(arrays___err_non_array), ARRAYS_ERR_CASE(arrays___err_wrong_val_type1), ARRAYS_ERR_CASE(arrays___err_wrong_val_type2), + ARRAYS_ERR_CASE(arrays___err_bad_zero_sz_arr), /* enum/ptr/int handling scenarios */ PRIMITIVES_CASE(primitives), diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___equiv_zero_sz_arr.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___equiv_zero_sz_arr.c new file mode 100644 index 000000000000..65eac371b061 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___equiv_zero_sz_arr.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays___equiv_zero_sz_arr x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_bad_zero_sz_arr.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_bad_zero_sz_arr.c new file mode 100644 index 000000000000..ecda2b545ac2 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_bad_zero_sz_arr.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays___err_bad_zero_sz_arr x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___fixed_arr.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___fixed_arr.c new file mode 100644 index 000000000000..fe1d01232c22 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___fixed_arr.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays___fixed_arr x) {} diff --git a/tools/testing/selftests/bpf/progs/core_reloc_types.h b/tools/testing/selftests/bpf/progs/core_reloc_types.h index 9311489e14b2..6d598cfbdb3e 100644 --- a/tools/testing/selftests/bpf/progs/core_reloc_types.h +++ b/tools/testing/selftests/bpf/progs/core_reloc_types.h @@ -327,6 +327,7 @@ struct core_reloc_arrays_output { char b123; int c1c; int d00d; + int f10c; }; struct core_reloc_arrays_substruct { @@ -339,6 +340,7 @@ struct core_reloc_arrays { char b[2][3][4]; struct core_reloc_arrays_substruct c[3]; struct core_reloc_arrays_substruct d[1][2]; + struct core_reloc_arrays_substruct f[][2]; }; /* bigger array dimensions */ @@ -347,6 +349,7 @@ struct core_reloc_arrays___diff_arr_dim { char b[3][4][5]; struct core_reloc_arrays_substruct c[4]; struct core_reloc_arrays_substruct d[2][3]; + struct core_reloc_arrays_substruct f[1][3]; }; /* different size of array's value (struct) */ @@ -363,6 +366,29 @@ struct core_reloc_arrays___diff_arr_val_sz { int d; int __padding2; } d[1][2]; + struct { + int __padding1; + int c; + int __padding2; + } f[][2]; +}; + +struct core_reloc_arrays___equiv_zero_sz_arr { + int a[5]; + char b[2][3][4]; + struct core_reloc_arrays_substruct c[3]; + struct core_reloc_arrays_substruct d[1][2]; + /* equivalent to flexible array */ + struct core_reloc_arrays_substruct f[0][2]; +}; + +struct core_reloc_arrays___fixed_arr { + int a[5]; + char b[2][3][4]; + struct core_reloc_arrays_substruct c[3]; + struct core_reloc_arrays_substruct d[1][2]; + /* not a flexible array anymore, but within access bounds */ + struct core_reloc_arrays_substruct f[1][2]; }; struct core_reloc_arrays___err_too_small { @@ -370,6 +396,7 @@ struct core_reloc_arrays___err_too_small { char b[2][3][4]; struct core_reloc_arrays_substruct c[3]; struct core_reloc_arrays_substruct d[1][2]; + struct core_reloc_arrays_substruct f[][2]; }; struct core_reloc_arrays___err_too_shallow { @@ -377,6 +404,7 @@ struct core_reloc_arrays___err_too_shallow { char b[2][3]; /* this one lacks one dimension */ struct core_reloc_arrays_substruct c[3]; struct core_reloc_arrays_substruct d[1][2]; + struct core_reloc_arrays_substruct f[][2]; }; struct core_reloc_arrays___err_non_array { @@ -384,6 +412,7 @@ struct core_reloc_arrays___err_non_array { char b[2][3][4]; struct core_reloc_arrays_substruct c[3]; struct core_reloc_arrays_substruct d[1][2]; + struct core_reloc_arrays_substruct f[][2]; }; struct core_reloc_arrays___err_wrong_val_type { @@ -391,6 +420,16 @@ struct core_reloc_arrays___err_wrong_val_type { char b[2][3][4]; int c[3]; /* value is not a struct */ struct core_reloc_arrays_substruct d[1][2]; + struct core_reloc_arrays_substruct f[][2]; +}; + +struct core_reloc_arrays___err_bad_zero_sz_arr { + /* zero-sized array, but not at the end */ + struct core_reloc_arrays_substruct f[0][2]; + int a[5]; + char b[2][3][4]; + struct core_reloc_arrays_substruct c[3]; + struct core_reloc_arrays_substruct d[1][2]; }; /* diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c b/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c index 89951b684282..053b86f6b53f 100644 --- a/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c @@ -18,6 +18,7 @@ struct core_reloc_arrays_output { char b123; int c1c; int d00d; + int f01c; }; struct core_reloc_arrays_substruct { @@ -30,6 +31,7 @@ struct core_reloc_arrays { char b[2][3][4]; struct core_reloc_arrays_substruct c[3]; struct core_reloc_arrays_substruct d[1][2]; + struct core_reloc_arrays_substruct f[][2]; }; #define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*(dst)), src) @@ -40,18 +42,16 @@ int test_core_arrays(void *ctx) struct core_reloc_arrays *in = (void *)&data.in; struct core_reloc_arrays_output *out = (void *)&data.out; - /* in->a[2] */ if (CORE_READ(&out->a2, &in->a[2])) return 1; - /* in->b[1][2][3] */ if (CORE_READ(&out->b123, &in->b[1][2][3])) return 1; - /* in->c[1].c */ if (CORE_READ(&out->c1c, &in->c[1].c)) return 1; - /* in->d[0][0].d */ if (CORE_READ(&out->d00d, &in->d[0][0].d)) return 1; + if (CORE_READ(&out->f01c, &in->f[0][1].c)) + return 1; return 0; } |