diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/bpf/resolve_btfids/main.c | 28 | ||||
| -rw-r--r-- | tools/lib/bpf/bpf.c | 1 | ||||
| -rw-r--r-- | tools/lib/bpf/bpf_gen_internal.h | 16 | ||||
| -rw-r--r-- | tools/lib/bpf/btf.c | 18 | ||||
| -rw-r--r-- | tools/lib/bpf/gen_loader.c | 314 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 104 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf_internal.h | 3 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/Makefile | 9 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c | 23 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/ksyms_module.c | 29 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/ksyms_module_libbpf.c | 28 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/progs/test_ksyms_module.c | 46 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/verifier/calls.c | 23 |
13 files changed, 510 insertions, 132 deletions
diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c index de6365b53c9c..c6c3e613858a 100644 --- a/tools/bpf/resolve_btfids/main.c +++ b/tools/bpf/resolve_btfids/main.c @@ -89,6 +89,7 @@ struct btf_id { struct object { const char *path; const char *btf; + const char *base_btf_path; struct { int fd; @@ -477,16 +478,27 @@ static int symbols_resolve(struct object *obj) int nr_structs = obj->nr_structs; int nr_unions = obj->nr_unions; int nr_funcs = obj->nr_funcs; + struct btf *base_btf = NULL; int err, type_id; struct btf *btf; __u32 nr_types; - btf = btf__parse(obj->btf ?: obj->path, NULL); + if (obj->base_btf_path) { + base_btf = btf__parse(obj->base_btf_path, NULL); + err = libbpf_get_error(base_btf); + if (err) { + pr_err("FAILED: load base BTF from %s: %s\n", + obj->base_btf_path, strerror(-err)); + return -1; + } + } + + btf = btf__parse_split(obj->btf ?: obj->path, base_btf); err = libbpf_get_error(btf); if (err) { pr_err("FAILED: load BTF from %s: %s\n", obj->btf ?: obj->path, strerror(-err)); - return -1; + goto out; } err = -1; @@ -545,6 +557,7 @@ static int symbols_resolve(struct object *obj) err = 0; out: + btf__free(base_btf); btf__free(btf); return err; } @@ -678,7 +691,6 @@ static const char * const resolve_btfids_usage[] = { int main(int argc, const char **argv) { - bool no_fail = false; struct object obj = { .efile = { .idlist_shndx = -1, @@ -695,8 +707,8 @@ int main(int argc, const char **argv) "be more verbose (show errors, etc)"), OPT_STRING(0, "btf", &obj.btf, "BTF data", "BTF data"), - OPT_BOOLEAN(0, "no-fail", &no_fail, - "do not fail if " BTF_IDS_SECTION " section is not found"), + OPT_STRING('b', "btf_base", &obj.base_btf_path, "file", + "path of file providing base BTF"), OPT_END() }; int err = -1; @@ -717,10 +729,8 @@ int main(int argc, const char **argv) */ if (obj.efile.idlist_shndx == -1 || obj.efile.symbols_shndx == -1) { - if (no_fail) - return 0; - pr_err("FAILED to find needed sections\n"); - return -1; + pr_debug("Cannot find .BTF_ids or symbols sections, nothing to do\n"); + return 0; } if (symbols_collect(&obj)) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 2401fad090c5..7d1741ceaa32 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -264,6 +264,7 @@ int libbpf__bpf_prog_load(const struct bpf_prog_load_params *load_attr) attr.line_info_rec_size = load_attr->line_info_rec_size; attr.line_info_cnt = load_attr->line_info_cnt; attr.line_info = ptr_to_u64(load_attr->line_info); + attr.fd_array = ptr_to_u64(load_attr->fd_array); if (load_attr->name) memcpy(attr.prog_name, load_attr->name, diff --git a/tools/lib/bpf/bpf_gen_internal.h b/tools/lib/bpf/bpf_gen_internal.h index 615400391e57..70eccbffefb1 100644 --- a/tools/lib/bpf/bpf_gen_internal.h +++ b/tools/lib/bpf/bpf_gen_internal.h @@ -7,6 +7,15 @@ struct ksym_relo_desc { const char *name; int kind; int insn_idx; + bool is_weak; +}; + +struct ksym_desc { + const char *name; + int ref; + int kind; + int off; + int insn; }; struct bpf_gen { @@ -24,6 +33,10 @@ struct bpf_gen { int relo_cnt; char attach_target[128]; int attach_kind; + struct ksym_desc *ksyms; + __u32 nr_ksyms; + int fd_array; + int nr_fd_array; }; void bpf_gen__init(struct bpf_gen *gen, int log_level); @@ -36,6 +49,7 @@ void bpf_gen__prog_load(struct bpf_gen *gen, struct bpf_prog_load_params *load_a void bpf_gen__map_update_elem(struct bpf_gen *gen, int map_idx, void *value, __u32 value_size); void bpf_gen__map_freeze(struct bpf_gen *gen, int map_idx); void bpf_gen__record_attach_target(struct bpf_gen *gen, const char *name, enum bpf_attach_type type); -void bpf_gen__record_extern(struct bpf_gen *gen, const char *name, int kind, int insn_idx); +void bpf_gen__record_extern(struct bpf_gen *gen, const char *name, bool is_weak, int kind, + int insn_idx); #endif diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 6ad63e4d418a..7774f99afa6e 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -695,15 +695,15 @@ __s32 btf__find_by_name(const struct btf *btf, const char *type_name) return libbpf_err(-ENOENT); } -__s32 btf__find_by_name_kind(const struct btf *btf, const char *type_name, - __u32 kind) +static __s32 btf_find_by_name_kind(const struct btf *btf, int start_id, + const char *type_name, __u32 kind) { __u32 i, nr_types = btf__get_nr_types(btf); if (kind == BTF_KIND_UNKN || !strcmp(type_name, "void")) return 0; - for (i = 1; i <= nr_types; i++) { + for (i = start_id; i <= nr_types; i++) { const struct btf_type *t = btf__type_by_id(btf, i); const char *name; @@ -717,6 +717,18 @@ __s32 btf__find_by_name_kind(const struct btf *btf, const char *type_name, return libbpf_err(-ENOENT); } +__s32 btf__find_by_name_kind_own(const struct btf *btf, const char *type_name, + __u32 kind) +{ + return btf_find_by_name_kind(btf, btf->start_id, type_name, kind); +} + +__s32 btf__find_by_name_kind(const struct btf *btf, const char *type_name, + __u32 kind) +{ + return btf_find_by_name_kind(btf, 1, type_name, kind); +} + static bool btf_is_modifiable(const struct btf *btf) { return (void *)btf->hdr != btf->raw_data; diff --git a/tools/lib/bpf/gen_loader.c b/tools/lib/bpf/gen_loader.c index 80087b13877f..937bfc7db41e 100644 --- a/tools/lib/bpf/gen_loader.c +++ b/tools/lib/bpf/gen_loader.c @@ -14,8 +14,10 @@ #include "bpf_gen_internal.h" #include "skel_internal.h" -#define MAX_USED_MAPS 64 -#define MAX_USED_PROGS 32 +#define MAX_USED_MAPS 64 +#define MAX_USED_PROGS 32 +#define MAX_KFUNC_DESCS 256 +#define MAX_FD_ARRAY_SZ (MAX_USED_PROGS + MAX_KFUNC_DESCS) /* The following structure describes the stack layout of the loader program. * In addition R6 contains the pointer to context. @@ -30,7 +32,6 @@ */ struct loader_stack { __u32 btf_fd; - __u32 map_fd[MAX_USED_MAPS]; __u32 prog_fd[MAX_USED_PROGS]; __u32 inner_map_fd; }; @@ -143,13 +144,49 @@ static int add_data(struct bpf_gen *gen, const void *data, __u32 size) if (realloc_data_buf(gen, size8)) return 0; prev = gen->data_cur; - memcpy(gen->data_cur, data, size); - gen->data_cur += size; - memcpy(gen->data_cur, &zero, size8 - size); - gen->data_cur += size8 - size; + if (data) { + memcpy(gen->data_cur, data, size); + memcpy(gen->data_cur + size, &zero, size8 - size); + } else { + memset(gen->data_cur, 0, size8); + } + gen->data_cur += size8; return prev - gen->data_start; } +/* Get index for map_fd/btf_fd slot in reserved fd_array, or in data relative + * to start of fd_array. Caller can decide if it is usable or not. + */ +static int add_map_fd(struct bpf_gen *gen) +{ + if (!gen->fd_array) + gen->fd_array = add_data(gen, NULL, MAX_FD_ARRAY_SZ * sizeof(int)); + if (gen->nr_maps == MAX_USED_MAPS) { + pr_warn("Total maps exceeds %d\n", MAX_USED_MAPS); + gen->error = -E2BIG; + return 0; + } + return gen->nr_maps++; +} + +static int add_kfunc_btf_fd(struct bpf_gen *gen) +{ + int cur; + + if (!gen->fd_array) + gen->fd_array = add_data(gen, NULL, MAX_FD_ARRAY_SZ * sizeof(int)); + if (gen->nr_fd_array == MAX_KFUNC_DESCS) { + cur = add_data(gen, NULL, sizeof(int)); + return (cur - gen->fd_array) / sizeof(int); + } + return MAX_USED_MAPS + gen->nr_fd_array++; +} + +static int blob_fd_array_off(struct bpf_gen *gen, int index) +{ + return gen->fd_array + index * sizeof(int); +} + static int insn_bytes_to_bpf_size(__u32 sz) { switch (sz) { @@ -171,14 +208,22 @@ static void emit_rel_store(struct bpf_gen *gen, int off, int data) emit(gen, BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0)); } -/* *(u64 *)(blob + off) = (u64)(void *)(%sp + stack_off) */ -static void emit_rel_store_sp(struct bpf_gen *gen, int off, int stack_off) +static void move_blob2blob(struct bpf_gen *gen, int off, int size, int blob_off) { - emit(gen, BPF_MOV64_REG(BPF_REG_0, BPF_REG_10)); - emit(gen, BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, stack_off)); + emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_2, BPF_PSEUDO_MAP_IDX_VALUE, + 0, 0, 0, blob_off)); + emit(gen, BPF_LDX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_0, BPF_REG_2, 0)); emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE, 0, 0, 0, off)); - emit(gen, BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0)); + emit(gen, BPF_STX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_1, BPF_REG_0, 0)); +} + +static void move_blob2ctx(struct bpf_gen *gen, int ctx_off, int size, int blob_off) +{ + emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE, + 0, 0, 0, blob_off)); + emit(gen, BPF_LDX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_0, BPF_REG_1, 0)); + emit(gen, BPF_STX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_6, BPF_REG_0, ctx_off)); } static void move_ctx2blob(struct bpf_gen *gen, int off, int size, int ctx_off, @@ -326,11 +371,11 @@ int bpf_gen__finish(struct bpf_gen *gen) offsetof(struct bpf_prog_desc, prog_fd), 4, stack_off(prog_fd[i])); for (i = 0; i < gen->nr_maps; i++) - move_stack2ctx(gen, - sizeof(struct bpf_loader_ctx) + - sizeof(struct bpf_map_desc) * i + - offsetof(struct bpf_map_desc, map_fd), 4, - stack_off(map_fd[i])); + move_blob2ctx(gen, + sizeof(struct bpf_loader_ctx) + + sizeof(struct bpf_map_desc) * i + + offsetof(struct bpf_map_desc, map_fd), 4, + blob_fd_array_off(gen, i)); emit(gen, BPF_MOV64_IMM(BPF_REG_0, 0)); emit(gen, BPF_EXIT_INSN()); pr_debug("gen: finish %d\n", gen->error); @@ -390,7 +435,7 @@ void bpf_gen__map_create(struct bpf_gen *gen, { int attr_size = offsetofend(union bpf_attr, btf_vmlinux_value_type_id); bool close_inner_map_fd = false; - int map_create_attr; + int map_create_attr, idx; union bpf_attr attr; memset(&attr, 0, attr_size); @@ -467,9 +512,11 @@ void bpf_gen__map_create(struct bpf_gen *gen, gen->error = -EDOM; /* internal bug */ return; } else { - emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_7, - stack_off(map_fd[map_idx]))); - gen->nr_maps++; + /* add_map_fd does gen->nr_maps++ */ + idx = add_map_fd(gen); + emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE, + 0, 0, 0, blob_fd_array_off(gen, idx))); + emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_7, 0)); } if (close_inner_map_fd) emit_sys_close_stack(gen, stack_off(inner_map_fd)); @@ -511,8 +558,8 @@ static void emit_find_attach_target(struct bpf_gen *gen) */ } -void bpf_gen__record_extern(struct bpf_gen *gen, const char *name, int kind, - int insn_idx) +void bpf_gen__record_extern(struct bpf_gen *gen, const char *name, bool is_weak, + int kind, int insn_idx) { struct ksym_relo_desc *relo; @@ -524,38 +571,192 @@ void bpf_gen__record_extern(struct bpf_gen *gen, const char *name, int kind, gen->relos = relo; relo += gen->relo_cnt; relo->name = name; + relo->is_weak = is_weak; relo->kind = kind; relo->insn_idx = insn_idx; gen->relo_cnt++; } -static void emit_relo(struct bpf_gen *gen, struct ksym_relo_desc *relo, int insns) +/* returns existing ksym_desc with ref incremented, or inserts a new one */ +static struct ksym_desc *get_ksym_desc(struct bpf_gen *gen, struct ksym_relo_desc *relo) { - int name, insn, len = strlen(relo->name) + 1; + struct ksym_desc *kdesc; - pr_debug("gen: emit_relo: %s at %d\n", relo->name, relo->insn_idx); - name = add_data(gen, relo->name, len); + for (int i = 0; i < gen->nr_ksyms; i++) { + if (!strcmp(gen->ksyms[i].name, relo->name)) { + gen->ksyms[i].ref++; + return &gen->ksyms[i]; + } + } + kdesc = libbpf_reallocarray(gen->ksyms, gen->nr_ksyms + 1, sizeof(*kdesc)); + if (!kdesc) { + gen->error = -ENOMEM; + return NULL; + } + gen->ksyms = kdesc; + kdesc = &gen->ksyms[gen->nr_ksyms++]; + kdesc->name = relo->name; + kdesc->kind = relo->kind; + kdesc->ref = 1; + kdesc->off = 0; + kdesc->insn = 0; + return kdesc; +} + +/* Overwrites BPF_REG_{0, 1, 2, 3, 4, 7} + * Returns result in BPF_REG_7 + */ +static void emit_bpf_find_by_name_kind(struct bpf_gen *gen, struct ksym_relo_desc *relo) +{ + int name_off, len = strlen(relo->name) + 1; + name_off = add_data(gen, relo->name, len); emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE, - 0, 0, 0, name)); + 0, 0, 0, name_off)); emit(gen, BPF_MOV64_IMM(BPF_REG_2, len)); emit(gen, BPF_MOV64_IMM(BPF_REG_3, relo->kind)); emit(gen, BPF_MOV64_IMM(BPF_REG_4, 0)); emit(gen, BPF_EMIT_CALL(BPF_FUNC_btf_find_by_name_kind)); emit(gen, BPF_MOV64_REG(BPF_REG_7, BPF_REG_0)); debug_ret(gen, "find_by_name_kind(%s,%d)", relo->name, relo->kind); - emit_check_err(gen); +} + +/* Expects: + * BPF_REG_8 - pointer to instruction + * + * We need to reuse BTF fd for same symbol otherwise each relocation takes a new + * index, while kernel limits total kfunc BTFs to 256. For duplicate symbols, + * this would mean a new BTF fd index for each entry. By pairing symbol name + * with index, we get the insn->imm, insn->off pairing that kernel uses for + * kfunc_tab, which becomes the effective limit even though all of them may + * share same index in fd_array (such that kfunc_btf_tab has 1 element). + */ +static void emit_relo_kfunc_btf(struct bpf_gen *gen, struct ksym_relo_desc *relo, int insn) +{ + struct ksym_desc *kdesc; + int btf_fd_idx; + + kdesc = get_ksym_desc(gen, relo); + if (!kdesc) + return; + /* try to copy from existing bpf_insn */ + if (kdesc->ref > 1) { + move_blob2blob(gen, insn + offsetof(struct bpf_insn, imm), 4, + kdesc->insn + offsetof(struct bpf_insn, imm)); + move_blob2blob(gen, insn + offsetof(struct bpf_insn, off), 2, + kdesc->insn + offsetof(struct bpf_insn, off)); + goto log; + } + /* remember insn offset, so we can copy BTF ID and FD later */ + kdesc->insn = insn; + emit_bpf_find_by_name_kind(gen, relo); + if (!relo->is_weak) + emit_check_err(gen); + /* get index in fd_array to store BTF FD at */ + btf_fd_idx = add_kfunc_btf_fd(gen); + if (btf_fd_idx > INT16_MAX) { + pr_warn("BTF fd off %d for kfunc %s exceeds INT16_MAX, cannot process relocation\n", + btf_fd_idx, relo->name); + gen->error = -E2BIG; + return; + } + kdesc->off = btf_fd_idx; + /* set a default value for imm */ + emit(gen, BPF_ST_MEM(BPF_W, BPF_REG_8, offsetof(struct bpf_insn, imm), 0)); + /* skip success case store if ret < 0 */ + emit(gen, BPF_JMP_IMM(BPF_JSLT, BPF_REG_7, 0, 1)); /* store btf_id into insn[insn_idx].imm */ - insn = insns + sizeof(struct bpf_insn) * relo->insn_idx + - offsetof(struct bpf_insn, imm); + emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_8, BPF_REG_7, offsetof(struct bpf_insn, imm))); + /* load fd_array slot pointer */ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_0, BPF_PSEUDO_MAP_IDX_VALUE, - 0, 0, 0, insn)); - emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_7, 0)); - if (relo->kind == BTF_KIND_VAR) { - /* store btf_obj_fd into insn[insn_idx + 1].imm */ - emit(gen, BPF_ALU64_IMM(BPF_RSH, BPF_REG_7, 32)); - emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_7, - sizeof(struct bpf_insn))); + 0, 0, 0, blob_fd_array_off(gen, btf_fd_idx))); + /* skip store of BTF fd if ret < 0 */ + emit(gen, BPF_JMP_IMM(BPF_JSLT, BPF_REG_7, 0, 3)); + /* store BTF fd in slot */ + emit(gen, BPF_MOV64_REG(BPF_REG_9, BPF_REG_7)); + emit(gen, BPF_ALU64_IMM(BPF_RSH, BPF_REG_9, 32)); + emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_9, 0)); + /* set a default value for off */ + emit(gen, BPF_ST_MEM(BPF_H, BPF_REG_8, offsetof(struct bpf_insn, off), 0)); + /* skip insn->off store if ret < 0 */ + emit(gen, BPF_JMP_IMM(BPF_JSLT, BPF_REG_7, 0, 2)); + /* skip if vmlinux BTF */ + emit(gen, BPF_JMP_IMM(BPF_JEQ, BPF_REG_9, 0, 1)); + /* store index into insn[insn_idx].off */ + emit(gen, BPF_ST_MEM(BPF_H, BPF_REG_8, offsetof(struct bpf_insn, off), btf_fd_idx)); +log: + if (!gen->log_level) + return; + emit(gen, BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_8, + offsetof(struct bpf_insn, imm))); + emit(gen, BPF_LDX_MEM(BPF_H, BPF_REG_9, BPF_REG_8, + offsetof(struct bpf_insn, off))); + debug_regs(gen, BPF_REG_7, BPF_REG_9, " func (%s:count=%d): imm: %%d, off: %%d", + relo->name, kdesc->ref); + emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_0, BPF_PSEUDO_MAP_IDX_VALUE, + 0, 0, 0, blob_fd_array_off(gen, kdesc->off))); + emit(gen, BPF_LDX_MEM(BPF_W, BPF_REG_9, BPF_REG_0, 0)); + debug_regs(gen, BPF_REG_9, -1, " func (%s:count=%d): btf_fd", + relo->name, kdesc->ref); +} + +/* Expects: + * BPF_REG_8 - pointer to instruction + */ +static void emit_relo_ksym_btf(struct bpf_gen *gen, struct ksym_relo_desc *relo, int insn) +{ + struct ksym_desc *kdesc; + + kdesc = get_ksym_desc(gen, relo); + if (!kdesc) + return; + /* try to copy from existing ldimm64 insn */ + if (kdesc->ref > 1) { + move_blob2blob(gen, insn + offsetof(struct bpf_insn, imm), 4, + kdesc->insn + offsetof(struct bpf_insn, imm)); + move_blob2blob(gen, insn + sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm), 4, + kdesc->insn + sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm)); + goto log; + } + /* remember insn offset, so we can copy BTF ID and FD later */ + kdesc->insn = insn; + emit_bpf_find_by_name_kind(gen, relo); + emit_check_err(gen); + /* store btf_id into insn[insn_idx].imm */ + emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_8, BPF_REG_7, offsetof(struct bpf_insn, imm))); + /* store btf_obj_fd into insn[insn_idx + 1].imm */ + emit(gen, BPF_ALU64_IMM(BPF_RSH, BPF_REG_7, 32)); + emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_8, BPF_REG_7, + sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm))); +log: + if (!gen->log_level) + return; + emit(gen, BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_8, + offsetof(struct bpf_insn, imm))); + emit(gen, BPF_LDX_MEM(BPF_H, BPF_REG_9, BPF_REG_8, sizeof(struct bpf_insn) + + offsetof(struct bpf_insn, imm))); + debug_regs(gen, BPF_REG_7, BPF_REG_9, " var (%s:count=%d): imm: %%d, fd: %%d", + relo->name, kdesc->ref); +} + +static void emit_relo(struct bpf_gen *gen, struct ksym_relo_desc *relo, int insns) +{ + int insn; + + pr_debug("gen: emit_relo (%d): %s at %d\n", relo->kind, relo->name, relo->insn_idx); + insn = insns + sizeof(struct bpf_insn) * relo->insn_idx; + emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_8, BPF_PSEUDO_MAP_IDX_VALUE, 0, 0, 0, insn)); + switch (relo->kind) { + case BTF_KIND_VAR: + emit_relo_ksym_btf(gen, relo, insn); + break; + case BTF_KIND_FUNC: + emit_relo_kfunc_btf(gen, relo, insn); + break; + default: + pr_warn("Unknown relocation kind '%d'\n", relo->kind); + gen->error = -EDOM; + return; } } @@ -571,14 +772,22 @@ static void cleanup_relos(struct bpf_gen *gen, int insns) { int i, insn; - for (i = 0; i < gen->relo_cnt; i++) { - if (gen->relos[i].kind != BTF_KIND_VAR) - continue; - /* close fd recorded in insn[insn_idx + 1].imm */ - insn = insns + - sizeof(struct bpf_insn) * (gen->relos[i].insn_idx + 1) + - offsetof(struct bpf_insn, imm); - emit_sys_close_blob(gen, insn); + for (i = 0; i < gen->nr_ksyms; i++) { + if (gen->ksyms[i].kind == BTF_KIND_VAR) { + /* close fd recorded in insn[insn_idx + 1].imm */ + insn = gen->ksyms[i].insn; + insn += sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm); + emit_sys_close_blob(gen, insn); + } else { /* BTF_KIND_FUNC */ + emit_sys_close_blob(gen, blob_fd_array_off(gen, gen->ksyms[i].off)); + if (gen->ksyms[i].off < MAX_FD_ARRAY_SZ) + gen->nr_fd_array--; + } + } + if (gen->nr_ksyms) { + free(gen->ksyms); + gen->nr_ksyms = 0; + gen->ksyms = NULL; } if (gen->relo_cnt) { free(gen->relos); @@ -637,9 +846,8 @@ void bpf_gen__prog_load(struct bpf_gen *gen, /* populate union bpf_attr with a pointer to line_info */ emit_rel_store(gen, attr_field(prog_load_attr, line_info), line_info); - /* populate union bpf_attr fd_array with a pointer to stack where map_fds are saved */ - emit_rel_store_sp(gen, attr_field(prog_load_attr, fd_array), - stack_off(map_fd[0])); + /* populate union bpf_attr fd_array with a pointer to data where map_fds are saved */ + emit_rel_store(gen, attr_field(prog_load_attr, fd_array), gen->fd_array); /* populate union bpf_attr with user provided log details */ move_ctx2blob(gen, attr_field(prog_load_attr, log_level), 4, @@ -706,8 +914,8 @@ void bpf_gen__map_update_elem(struct bpf_gen *gen, int map_idx, void *pvalue, emit(gen, BPF_EMIT_CALL(BPF_FUNC_copy_from_user)); map_update_attr = add_data(gen, &attr, attr_size); - move_stack2blob(gen, attr_field(map_update_attr, map_fd), 4, - stack_off(map_fd[map_idx])); + move_blob2blob(gen, attr_field(map_update_attr, map_fd), 4, + blob_fd_array_off(gen, map_idx)); emit_rel_store(gen, attr_field(map_update_attr, key), key); emit_rel_store(gen, attr_field(map_update_attr, value), value); /* emit MAP_UPDATE_ELEM command */ @@ -725,8 +933,8 @@ void bpf_gen__map_freeze(struct bpf_gen *gen, int map_idx) memset(&attr, 0, attr_size); pr_debug("gen: map_freeze: idx %d\n", map_idx); map_freeze_attr = add_data(gen, &attr, attr_size); - move_stack2blob(gen, attr_field(map_freeze_attr, map_fd), 4, - stack_off(map_fd[map_idx])); + move_blob2blob(gen, attr_field(map_freeze_attr, map_fd), 4, + blob_fd_array_off(gen, map_idx)); /* emit MAP_FREEZE command */ emit_sys_bpf(gen, BPF_MAP_FREEZE, map_freeze_attr, attr_size); debug_ret(gen, "map_freeze"); diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index e23f1b6b9402..f32fa51b1e63 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -443,6 +443,11 @@ struct extern_desc { /* local btf_id of the ksym extern's type. */ __u32 type_id; + /* BTF fd index to be patched in for insn->off, this is + * 0 for vmlinux BTF, index in obj->fd_array for module + * BTF + */ + __s16 btf_fd_idx; } ksym; }; }; @@ -454,6 +459,7 @@ struct module_btf { char *name; __u32 id; int fd; + int fd_array_idx; }; struct bpf_object { @@ -539,6 +545,10 @@ struct bpf_object { void *priv; bpf_object_clear_priv_t clear_priv; + int *fd_array; + size_t fd_array_cap; + size_t fd_array_cnt; + char path[]; }; #define obj_elf_valid(o) ((o)->efile.elf) @@ -3429,11 +3439,6 @@ static int bpf_object__collect_externs(struct bpf_object *obj) return -ENOTSUP; } } else if (strcmp(sec_name, KSYMS_SEC) == 0) { - if (btf_is_func(t) && ext->is_weak) { - pr_warn("extern weak function %s is unsupported\n", - ext->name); - return -ENOTSUP; - } ksym_sec = sec; ext->type = EXT_KSYM; skip_mods_and_typedefs(obj->btf, t->type, @@ -5406,7 +5411,13 @@ bpf_object__relocate_data(struct bpf_object *obj, struct bpf_program *prog) case RELO_EXTERN_FUNC: ext = &obj->externs[relo->sym_off]; insn[0].src_reg = BPF_PSEUDO_KFUNC_CALL; - insn[0].imm = ext->ksym.kernel_btf_id; + if (ext->is_set) { + insn[0].imm = ext->ksym.kernel_btf_id; + insn[0].off = ext->ksym.btf_fd_idx; + } else { /* unresolved weak kfunc */ + insn[0].imm = 0; + insn[0].off = 0; + } break; case RELO_SUBPROG_ADDR: if (insn[0].src_reg != BPF_PSEUDO_FUNC) { @@ -6236,6 +6247,7 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, } load_attr.log_level = prog->log_level; load_attr.prog_flags = prog->prog_flags; + load_attr.fd_array = prog->obj->fd_array; /* adjust load_attr if sec_def provides custom preload callback */ if (prog->sec_def && prog->sec_def->preload_fn) { @@ -6348,12 +6360,12 @@ static int bpf_program__record_externs(struct bpf_program *prog) ext->name); return -ENOTSUP; } - bpf_gen__record_extern(obj->gen_loader, ext->name, BTF_KIND_VAR, - relo->insn_idx); + bpf_gen__record_extern(obj->gen_loader, ext->name, ext->is_weak, + BTF_KIND_VAR, relo->insn_idx); break; case RELO_EXTERN_FUNC: - bpf_gen__record_extern(obj->gen_loader, ext->name, BTF_KIND_FUNC, - relo->insn_idx); + bpf_gen__record_extern(obj->gen_loader, ext->name, ext->is_weak, + BTF_KIND_FUNC, relo->insn_idx); break; default: continue; @@ -6752,13 +6764,14 @@ out: static int find_ksym_btf_id(struct bpf_object *obj, const char *ksym_name, __u16 kind, struct btf **res_btf, - int *res_btf_fd) + struct module_btf **res_mod_btf) { - int i, id, btf_fd, err; + struct module_btf *mod_btf; struct btf *btf; + int i, id, err; btf = obj->btf_vmlinux; - btf_fd = 0; + mod_btf = NULL; id = btf__find_by_name_kind(btf, ksym_name, kind); if (id == -ENOENT) { @@ -6767,10 +6780,10 @@ static int find_ksym_btf_id(struct bpf_object *obj, const char *ksym_name, return err; for (i = 0; i < obj->btf_module_cnt; i++) { - btf = obj->btf_modules[i].btf; - /* we assume module BTF FD is always >0 */ - btf_fd = obj->btf_modules[i].fd; - id = btf__find_by_name_kind(btf, ksym_name, kind); + /* we assume module_btf's BTF FD is always >0 */ + mod_btf = &obj->btf_modules[i]; + btf = mod_btf->btf; + id = btf__find_by_name_kind_own(btf, ksym_name, kind); if (id != -ENOENT) break; } @@ -6779,7 +6792,7 @@ static int find_ksym_btf_id(struct bpf_object *obj, const char *ksym_name, return -ESRCH; *res_btf = btf; - *res_btf_fd = btf_fd; + *res_mod_btf = mod_btf; return id; } @@ -6788,14 +6801,15 @@ static int bpf_object__resolve_ksym_var_btf_id(struct bpf_object *obj, { const struct btf_type *targ_var, *targ_type; __u32 targ_type_id, local_type_id; + struct module_btf *mod_btf = NULL; const char *targ_var_name; - int id, btf_fd = 0, err; struct btf *btf = NULL; + int id, err; - id = find_ksym_btf_id(obj, ext->name, BTF_KIND_VAR, &btf, &btf_fd); - if (id == -ESRCH && ext->is_weak) { - return 0; - } else if (id < 0) { + id = find_ksym_btf_id(obj, ext->name, BTF_KIND_VAR, &btf, &mod_btf); + if (id < 0) { + if (id == -ESRCH && ext->is_weak) + return 0; pr_warn("extern (var ksym) '%s': not found in kernel BTF\n", ext->name); return id; @@ -6827,7 +6841,7 @@ static int bpf_object__resolve_ksym_var_btf_id(struct bpf_object *obj, } ext->is_set = true; - ext->ksym.kernel_btf_obj_fd = btf_fd; + ext->ksym.kernel_btf_obj_fd = mod_btf ? mod_btf->fd : 0; ext->ksym.kernel_btf_id = id; pr_debug("extern (var ksym) '%s': resolved to [%d] %s %s\n", ext->name, id, btf_kind_str(targ_var), targ_var_name); @@ -6839,26 +6853,22 @@ static int bpf_object__resolve_ksym_func_btf_id(struct bpf_object *obj, struct extern_desc *ext) { int local_func_proto_id, kfunc_proto_id, kfunc_id; + struct module_btf *mod_btf = NULL; const struct btf_type *kern_func; struct btf *kern_btf = NULL; - int ret, kern_btf_fd = 0; + int ret; local_func_proto_id = ext->ksym.type_id; - kfunc_id = find_ksym_btf_id(obj, ext->name, BTF_KIND_FUNC, - &kern_btf, &kern_btf_fd); + kfunc_id = find_ksym_btf_id(obj, ext->name, BTF_KIND_FUNC, &kern_btf, &mod_btf); if (kfunc_id < 0) { - pr_warn("extern (func ksym) '%s': not found in kernel BTF\n", + if (kfunc_id == -ESRCH && ext->is_weak) + return 0; + pr_warn("extern (func ksym) '%s': not found in kernel or module BTFs\n", ext->name); return kfunc_id; } - if (kern_btf != obj->btf_vmlinux) { - pr_warn("extern (func ksym) '%s': function in kernel module is not supported\n", - ext->name); - return -ENOTSUP; - } - kern_func = btf__type_by_id(kern_btf, kfunc_id); kfunc_proto_id = kern_func->type; @@ -6870,9 +6880,30 @@ static int bpf_object__resolve_ksym_func_btf_id(struct bpf_object *obj, return -EINVAL; } + /* set index for module BTF fd in fd_array, if unset */ + if (mod_btf && !mod_btf->fd_array_idx) { + /* insn->off is s16 */ + if (obj->fd_array_cnt == INT16_MAX) { + pr_warn("extern (func ksym) '%s': module BTF fd index %d too big to fit in bpf_insn offset\n", + ext->name, mod_btf->fd_array_idx); + return -E2BIG; + } + /* Cannot use index 0 for module BTF fd */ + if (!obj->fd_array_cnt) + obj->fd_array_cnt = 1; + + ret = libbpf_ensure_mem((void **)&obj->fd_array, &obj->fd_array_cap, sizeof(int), + obj->fd_array_cnt + 1); + if (ret) + return ret; + mod_btf->fd_array_idx = obj->fd_array_cnt; + /* we assume module BTF FD is always >0 */ + obj->fd_array[obj->fd_array_cnt++] = mod_btf->fd; + } + ext->is_set = true; - ext->ksym.kernel_btf_obj_fd = kern_btf_fd; ext->ksym.kernel_btf_id = kfunc_id; + ext->ksym.btf_fd_idx = mod_btf ? mod_btf->fd_array_idx : 0; pr_debug("extern (func ksym) '%s': resolved to kernel [%d]\n", ext->name, kfunc_id); @@ -7031,6 +7062,9 @@ int bpf_object__load_xattr(struct bpf_object_load_attr *attr) err = bpf_gen__finish(obj->gen_loader); } + /* clean up fd_array */ + zfree(&obj->fd_array); + /* clean up module BTFs */ for (i = 0; i < obj->btf_module_cnt; i++) { close(obj->btf_modules[i].fd); diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index ec79400517d4..f7fd3944d46d 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -298,6 +298,7 @@ struct bpf_prog_load_params { __u32 log_level; char *log_buf; size_t log_buf_sz; + int *fd_array; }; int libbpf__bpf_prog_load(const struct bpf_prog_load_params *load_attr); @@ -408,6 +409,8 @@ int btf_type_visit_type_ids(struct btf_type *t, type_id_visit_fn visit, void *ct int btf_type_visit_str_offs(struct btf_type *t, str_off_visit_fn visit, void *ctx); int btf_ext_visit_type_ids(struct btf_ext *btf_ext, type_id_visit_fn visit, void *ctx); int btf_ext_visit_str_offs(struct btf_ext *btf_ext, str_off_visit_fn visit, void *ctx); +__s32 btf__find_by_name_kind_own(const struct btf *btf, const char *type_name, + __u32 kind); extern enum libbpf_strict_mode libbpf_mode; diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index aa94739a1835..c5c9a9f50d8d 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -315,8 +315,9 @@ LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h \ linked_vars.skel.h linked_maps.skel.h LSKELS := kfunc_call_test.c fentry_test.c fexit_test.c fexit_sleep.c \ - test_ksyms_module.c test_ringbuf.c atomics.c trace_printk.c \ - trace_vprintk.c + test_ringbuf.c atomics.c trace_printk.c trace_vprintk.c +# Generate both light skeleton and libbpf skeleton for these +LSKELS_EXTRA := test_ksyms_module.c SKEL_BLACKLIST += $$(LSKELS) test_static_linked.skel.h-deps := test_static_linked1.o test_static_linked2.o @@ -346,7 +347,7 @@ TRUNNER_BPF_OBJS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.o, $$(TRUNNER_BPF_SRCS) TRUNNER_BPF_SKELS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.skel.h, \ $$(filter-out $(SKEL_BLACKLIST) $(LINKED_BPF_SRCS),\ $$(TRUNNER_BPF_SRCS))) -TRUNNER_BPF_LSKELS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.lskel.h, $$(LSKELS)) +TRUNNER_BPF_LSKELS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.lskel.h, $$(LSKELS) $$(LSKELS_EXTRA)) TRUNNER_BPF_SKELS_LINKED := $$(addprefix $$(TRUNNER_OUTPUT)/,$(LINKED_SKELS)) TEST_GEN_FILES += $$(TRUNNER_BPF_OBJS) @@ -454,7 +455,7 @@ $(OUTPUT)/$(TRUNNER_BINARY): $(TRUNNER_TEST_OBJS) \ | $(TRUNNER_BINARY)-extras $$(call msg,BINARY,,$$@) $(Q)$$(CC) $$(CFLAGS) $$(filter %.a %.o,$$^) $$(LDLIBS) -o $$@ - $(Q)$(RESOLVE_BTFIDS) --no-fail --btf $(TRUNNER_OUTPUT)/btf_data.o $$@ + $(Q)$(RESOLVE_BTFIDS) --btf $(TRUNNER_OUTPUT)/btf_data.o $$@ endef diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c index 50fc5561110a..b892948dc134 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c @@ -1,5 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2020 Facebook */ +#include <linux/btf.h> +#include <linux/btf_ids.h> #include <linux/error-injection.h> #include <linux/init.h> #include <linux/module.h> @@ -13,6 +15,12 @@ DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123; +noinline void +bpf_testmod_test_mod_kfunc(int i) +{ + *(int *)this_cpu_ptr(&bpf_testmod_ksym_percpu) = i; +} + noinline int bpf_testmod_loop_test(int n) { int i, sum = 0; @@ -71,13 +79,26 @@ static struct bin_attribute bin_attr_bpf_testmod_file __ro_after_init = { .write = bpf_testmod_test_write, }; +BTF_SET_START(bpf_testmod_kfunc_ids) +BTF_ID(func, bpf_testmod_test_mod_kfunc) +BTF_SET_END(bpf_testmod_kfunc_ids) + +static DEFINE_KFUNC_BTF_ID_SET(&bpf_testmod_kfunc_ids, bpf_testmod_kfunc_btf_set); + static int bpf_testmod_init(void) { - return sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file); + int ret; + + ret = sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file); + if (ret) + return ret; + register_kfunc_btf_id_set(&prog_test_kfunc_list, &bpf_testmod_kfunc_btf_set); + return 0; } static void bpf_testmod_exit(void) { + unregister_kfunc_btf_id_set(&prog_test_kfunc_list, &bpf_testmod_kfunc_btf_set); return sysfs_remove_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file); } diff --git a/tools/testing/selftests/bpf/prog_tests/ksyms_module.c b/tools/testing/selftests/bpf/prog_tests/ksyms_module.c index 2cd5cded543f..831447878d7b 100644 --- a/tools/testing/selftests/bpf/prog_tests/ksyms_module.c +++ b/tools/testing/selftests/bpf/prog_tests/ksyms_module.c @@ -2,30 +2,29 @@ /* Copyright (c) 2021 Facebook */ #include <test_progs.h> -#include <bpf/libbpf.h> -#include <bpf/btf.h> +#include <network_helpers.h> #include "test_ksyms_module.lskel.h" -static int duration; - void test_ksyms_module(void) { - struct test_ksyms_module* skel; + struct test_ksyms_module *skel; + int retval; int err; - skel = test_ksyms_module__open_and_load(); - if (CHECK(!skel, "skel_open", "failed to open skeleton\n")) + if (!env.has_testmod) { + test__skip(); return; + } - err = test_ksyms_module__attach(skel); - if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err)) + skel = test_ksyms_module__open_and_load(); + if (!ASSERT_OK_PTR(skel, "test_ksyms_module__open_and_load")) + return; + err = bpf_prog_test_run(skel->progs.load.prog_fd, 1, &pkt_v4, sizeof(pkt_v4), + NULL, NULL, (__u32 *)&retval, NULL); + if (!ASSERT_OK(err, "bpf_prog_test_run")) goto cleanup; - - usleep(1); - - ASSERT_EQ(skel->bss->triggered, true, "triggered"); - ASSERT_EQ(skel->bss->out_mod_ksym_global, 123, "global_ksym_val"); - + ASSERT_EQ(retval, 0, "retval"); + ASSERT_EQ(skel->bss->out_bpf_testmod_ksym, 42, "bpf_testmod_ksym"); cleanup: test_ksyms_module__destroy(skel); } diff --git a/tools/testing/selftests/bpf/prog_tests/ksyms_module_libbpf.c b/tools/testing/selftests/bpf/prog_tests/ksyms_module_libbpf.c new file mode 100644 index 000000000000..e6343ef63af9 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/ksyms_module_libbpf.c @@ -0,0 +1,28 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <test_progs.h> +#include <network_helpers.h> +#include "test_ksyms_module.skel.h" + +void test_ksyms_module_libbpf(void) +{ + struct test_ksyms_module *skel; + int retval, err; + + if (!env.has_testmod) { + test__skip(); + return; + } + + skel = test_ksyms_module__open_and_load(); + if (!ASSERT_OK_PTR(skel, "test_ksyms_module__open")) + return; + err = bpf_prog_test_run(bpf_program__fd(skel->progs.load), 1, &pkt_v4, + sizeof(pkt_v4), NULL, NULL, (__u32 *)&retval, NULL); + if (!ASSERT_OK(err, "bpf_prog_test_run")) + goto cleanup; + ASSERT_EQ(retval, 0, "retval"); + ASSERT_EQ(skel->bss->out_bpf_testmod_ksym, 42, "bpf_testmod_ksym"); +cleanup: + test_ksyms_module__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_ksyms_module.c b/tools/testing/selftests/bpf/progs/test_ksyms_module.c index d6a0b3086b90..0650d918c096 100644 --- a/tools/testing/selftests/bpf/progs/test_ksyms_module.c +++ b/tools/testing/selftests/bpf/progs/test_ksyms_module.c @@ -2,24 +2,48 @@ /* Copyright (c) 2021 Facebook */ #include "vmlinux.h" - #include <bpf/bpf_helpers.h> +#define X_0(x) +#define X_1(x) x X_0(x) +#define X_2(x) x X_1(x) +#define X_3(x) x X_2(x) +#define X_4(x) x X_3(x) +#define X_5(x) x X_4(x) +#define X_6(x) x X_5(x) +#define X_7(x) x X_6(x) +#define X_8(x) x X_7(x) +#define X_9(x) x X_8(x) +#define X_10(x) x X_9(x) +#define REPEAT_256(Y) X_2(X_10(X_10(Y))) X_5(X_10(Y)) X_6(Y) + extern const int bpf_testmod_ksym_percpu __ksym; +extern void bpf_testmod_test_mod_kfunc(int i) __ksym; +extern void bpf_testmod_invalid_mod_kfunc(void) __ksym __weak; -int out_mod_ksym_global = 0; -bool triggered = false; +int out_bpf_testmod_ksym = 0; +const volatile int x = 0; -SEC("raw_tp/sys_enter") -int handler(const void *ctx) +SEC("tc") +int load(struct __sk_buff *skb) { - int *val; - __u32 cpu; - - val = (int *)bpf_this_cpu_ptr(&bpf_testmod_ksym_percpu); - out_mod_ksym_global = *val; - triggered = true; + /* This will be kept by clang, but removed by verifier. Since it is + * marked as __weak, libbpf and gen_loader don't error out if BTF ID + * is not found for it, instead imm and off is set to 0 for it. + */ + if (x) + bpf_testmod_invalid_mod_kfunc(); + bpf_testmod_test_mod_kfunc(42); + out_bpf_testmod_ksym = *(int *)bpf_this_cpu_ptr(&bpf_testmod_ksym_percpu); + return 0; +} +SEC("tc") +int load_256(struct __sk_buff *skb) +{ + /* this will fail if kfunc doesn't reuse its own btf fd index */ + REPEAT_256(bpf_testmod_test_mod_kfunc(42);); + bpf_testmod_test_mod_kfunc(42); return 0; } diff --git a/tools/testing/selftests/bpf/verifier/calls.c b/tools/testing/selftests/bpf/verifier/calls.c index 336a749673d1..d7b74eb28333 100644 --- a/tools/testing/selftests/bpf/verifier/calls.c +++ b/tools/testing/selftests/bpf/verifier/calls.c @@ -1,4 +1,27 @@ { + "calls: invalid kfunc call not eliminated", + .insns = { + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0), + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_TRACEPOINT, + .result = REJECT, + .errstr = "invalid kernel function call not eliminated in verifier pass", +}, +{ + "calls: invalid kfunc call unreachable", + .insns = { + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_JMP_IMM(BPF_JGT, BPF_REG_0, 0, 2), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0), + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_TRACEPOINT, + .result = ACCEPT, +}, +{ "calls: basic sanity", .insns = { BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 2), |