diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 428789a9e736..b52dc64ec92d 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -2113,6 +2113,11 @@ static inline void bpf_prog_put_recursion_context(struct bpf_prog *prog) #endif } +static inline bool is_tracing_multi(enum bpf_attach_type type) +{ + return type == BPF_TRACE_FENTRY_MULTI || type == BPF_TRACE_FEXIT_MULTI; +} + #if defined(CONFIG_BPF_JIT) && defined(CONFIG_BPF_SYSCALL) /* This macro helps developer to register a struct_ops type and generate * type information correctly. Developers should use this macro to register diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h index af011db39ab3..8b5a9ee92513 100644 --- a/include/linux/btf_ids.h +++ b/include/linux/btf_ids.h @@ -284,5 +284,6 @@ extern u32 bpf_cgroup_btf_id[]; extern u32 bpf_local_storage_map_btf_id[]; extern u32 btf_bpf_map_id[]; extern u32 bpf_kmem_cache_btf_id[]; +extern u32 bpf_multi_func_btf_id[]; #endif diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index d5238df5e5eb..28d127e5040a 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1156,6 +1156,8 @@ enum bpf_attach_type { BPF_TRACE_KPROBE_SESSION, BPF_TRACE_UPROBE_SESSION, BPF_TRACE_FSESSION, + BPF_TRACE_FENTRY_MULTI, + BPF_TRACE_FEXIT_MULTI, __MAX_BPF_ATTACH_TYPE }; diff --git a/kernel/bpf/fixups.c b/kernel/bpf/fixups.c index 5aa3f7d99ac9..0cf9735929f5 100644 --- a/kernel/bpf/fixups.c +++ b/kernel/bpf/fixups.c @@ -2186,6 +2186,7 @@ int bpf_do_misc_fixups(struct bpf_verifier_env *env) insn->imm == BPF_FUNC_get_func_ret) { if (eatype == BPF_TRACE_FEXIT || eatype == BPF_TRACE_FSESSION || + eatype == BPF_TRACE_FEXIT_MULTI || eatype == BPF_MODIFY_RETURN) { /* Load nr_args from ctx - 8 */ insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8); diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 0cfc8bcb3dc9..efdd6639a598 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -41,6 +41,7 @@ #include #include #include +#include #include #include @@ -2719,7 +2720,8 @@ static int bpf_prog_load_check_attach(enum bpf_prog_type prog_type, enum bpf_attach_type expected_attach_type, struct btf *attach_btf, u32 btf_id, - struct bpf_prog *dst_prog) + struct bpf_prog *dst_prog, + bool multi_func) { if (btf_id) { if (btf_id > BTF_MAX_TYPE) @@ -2739,6 +2741,14 @@ bpf_prog_load_check_attach(enum bpf_prog_type prog_type, } } + if (multi_func) { + if (prog_type != BPF_PROG_TYPE_TRACING) + return -EINVAL; + if (!attach_btf || btf_id) + return -EINVAL; + return 0; + } + if (attach_btf && (!btf_id || dst_prog)) return -EINVAL; @@ -2946,6 +2956,11 @@ static int bpf_prog_mark_insn_arrays_ready(struct bpf_prog *prog) return 0; } +extern int bpf_multi_func(void); +int __init __used bpf_multi_func(void) { return 0; } + +BTF_ID_LIST_GLOBAL_SINGLE(bpf_multi_func_btf_id, func, bpf_multi_func) + /* last field in 'union bpf_attr' used by this command */ #define BPF_PROG_LOAD_LAST_FIELD keyring_id @@ -2958,6 +2973,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_at bool bpf_cap; int err; char license[128]; + bool multi_func; if (CHECK_ATTR(BPF_PROG_LOAD)) return -EINVAL; @@ -3024,6 +3040,8 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_at if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON)) goto put_token; + multi_func = is_tracing_multi(attr->expected_attach_type); + /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog * or btf, we need to check which one it is */ @@ -3045,7 +3063,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_at goto put_token; } } - } else if (attr->attach_btf_id) { + } else if (attr->attach_btf_id || multi_func) { /* fall back to vmlinux BTF, if BTF type ID is specified */ attach_btf = bpf_get_btf_vmlinux(); if (IS_ERR(attach_btf)) { @@ -3061,7 +3079,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_at if (bpf_prog_load_check_attach(type, attr->expected_attach_type, attach_btf, attr->attach_btf_id, - dst_prog)) { + dst_prog, multi_func)) { if (dst_prog) bpf_prog_put(dst_prog); if (attach_btf) @@ -3084,7 +3102,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_at prog->expected_attach_type = attr->expected_attach_type; prog->sleepable = !!(attr->prog_flags & BPF_F_SLEEPABLE); prog->aux->attach_btf = attach_btf; - prog->aux->attach_btf_id = attr->attach_btf_id; + prog->aux->attach_btf_id = multi_func ? bpf_multi_func_btf_id[0] : attr->attach_btf_id; prog->aux->dst_prog = dst_prog; prog->aux->dev_bound = !!attr->prog_ifindex; prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS; @@ -4480,6 +4498,8 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type) case BPF_TRACE_FENTRY: case BPF_TRACE_FEXIT: case BPF_TRACE_FSESSION: + case BPF_TRACE_FENTRY_MULTI: + case BPF_TRACE_FEXIT_MULTI: case BPF_MODIFY_RETURN: return BPF_PROG_TYPE_TRACING; case BPF_LSM_MAC: diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index 5776d2b8e36e..ae7e4fdfe2a3 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -182,7 +182,8 @@ bool bpf_prog_has_trampoline(const struct bpf_prog *prog) switch (ptype) { case BPF_PROG_TYPE_TRACING: if (eatype == BPF_TRACE_FENTRY || eatype == BPF_TRACE_FEXIT || - eatype == BPF_MODIFY_RETURN || eatype == BPF_TRACE_FSESSION) + eatype == BPF_MODIFY_RETURN || eatype == BPF_TRACE_FSESSION || + eatype == BPF_TRACE_FENTRY_MULTI || eatype == BPF_TRACE_FEXIT_MULTI) return true; return false; case BPF_PROG_TYPE_LSM: @@ -781,10 +782,12 @@ static enum bpf_tramp_prog_type bpf_attach_type_to_tramp(struct bpf_prog *prog) { switch (prog->expected_attach_type) { case BPF_TRACE_FENTRY: + case BPF_TRACE_FENTRY_MULTI: return BPF_TRAMP_FENTRY; case BPF_MODIFY_RETURN: return BPF_TRAMP_MODIFY_RETURN; case BPF_TRACE_FEXIT: + case BPF_TRACE_FEXIT_MULTI: return BPF_TRAMP_FEXIT; case BPF_TRACE_FSESSION: return BPF_TRAMP_FSESSION; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 926ff63a0b61..0e593f3335e9 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -16382,6 +16382,8 @@ static bool return_retval_range(struct bpf_verifier_env *env, struct bpf_retval_ case BPF_TRACE_FENTRY: case BPF_TRACE_FEXIT: case BPF_TRACE_FSESSION: + case BPF_TRACE_FENTRY_MULTI: + case BPF_TRACE_FEXIT_MULTI: *range = retval_range(0, 0); break; case BPF_TRACE_RAW_TP: @@ -18772,6 +18774,11 @@ static int check_attach_modify_return(unsigned long addr, const char *func_name) #endif /* CONFIG_FUNCTION_ERROR_INJECTION */ +static bool is_tracing_multi_id(const struct bpf_prog *prog, u32 btf_id) +{ + return is_tracing_multi(prog->expected_attach_type) && bpf_multi_func_btf_id[0] == btf_id; +} + int bpf_check_attach_target(struct bpf_verifier_log *log, const struct bpf_prog *prog, const struct bpf_prog *tgt_prog, @@ -18894,6 +18901,8 @@ int bpf_check_attach_target(struct bpf_verifier_log *log, prog_extension && (tgt_prog->expected_attach_type == BPF_TRACE_FENTRY || tgt_prog->expected_attach_type == BPF_TRACE_FEXIT || + tgt_prog->expected_attach_type == BPF_TRACE_FENTRY_MULTI || + tgt_prog->expected_attach_type == BPF_TRACE_FEXIT_MULTI || tgt_prog->expected_attach_type == BPF_TRACE_FSESSION)) { /* Program extensions can extend all program types * except fentry/fexit. The reason is the following. @@ -19000,6 +19009,8 @@ int bpf_check_attach_target(struct bpf_verifier_log *log, case BPF_TRACE_FENTRY: case BPF_TRACE_FEXIT: case BPF_TRACE_FSESSION: + case BPF_TRACE_FENTRY_MULTI: + case BPF_TRACE_FEXIT_MULTI: if (prog->expected_attach_type == BPF_TRACE_FSESSION && !bpf_jit_supports_fsession()) { bpf_log(log, "JIT does not support fsession\n"); @@ -19029,7 +19040,18 @@ int bpf_check_attach_target(struct bpf_verifier_log *log, if (ret < 0) return ret; - if (tgt_prog) { + /* + * *.multi programs don't need an address during program + * verification, we just take the module ref if needed. + */ + if (is_tracing_multi_id(prog, btf_id)) { + if (btf_is_module(btf)) { + mod = btf_try_get_module(btf); + if (!mod) + return -ENOENT; + } + addr = 0; + } else if (tgt_prog) { if (subprog == 0) addr = (long) tgt_prog->bpf_func; else @@ -19057,6 +19079,12 @@ int bpf_check_attach_target(struct bpf_verifier_log *log, ret = -EINVAL; switch (prog->type) { case BPF_PROG_TYPE_TRACING: + /* *.multi sleepable programs will pass initial sleepable check, + * the actual attached btf ids are checked later during the link + * attachment. + */ + if (is_tracing_multi_id(prog, btf_id)) + ret = 0; if (!check_attach_sleepable(btf_id, addr, tname)) ret = 0; /* fentry/fexit/fmod_ret progs can also be sleepable if they are @@ -19167,6 +19195,8 @@ static bool can_be_sleepable(struct bpf_prog *prog) case BPF_TRACE_ITER: case BPF_TRACE_FSESSION: case BPF_TRACE_RAW_TP: + case BPF_TRACE_FENTRY_MULTI: + case BPF_TRACE_FEXIT_MULTI: return true; default: return false; @@ -19260,6 +19290,14 @@ static int check_attach_btf_id(struct bpf_verifier_env *env) return -EINVAL; } + /* + * We don't get trampoline for tracing_multi programs at this point, + * it's done when tracing_multi link is created. + */ + if (prog->type == BPF_PROG_TYPE_TRACING && + is_tracing_multi(prog->expected_attach_type)) + return 0; + key = bpf_trampoline_compute_key(tgt_prog, prog->aux->attach_btf, btf_id); tr = bpf_trampoline_get(key, &tgt_info); if (!tr) diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index c9aea7052ba7..67769c700cae 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -703,6 +703,8 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog, case BPF_TRACE_FENTRY: case BPF_TRACE_FEXIT: case BPF_TRACE_FSESSION: + case BPF_TRACE_FENTRY_MULTI: + case BPF_TRACE_FEXIT_MULTI: if (bpf_fentry_test1(1) != 2 || bpf_fentry_test2(2, 3) != 5 || bpf_fentry_test3(4, 5, 6) != 15 || diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 3829db087449..1b9aacf468e5 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1156,6 +1156,8 @@ enum bpf_attach_type { BPF_TRACE_KPROBE_SESSION, BPF_TRACE_UPROBE_SESSION, BPF_TRACE_FSESSION, + BPF_TRACE_FENTRY_MULTI, + BPF_TRACE_FEXIT_MULTI, __MAX_BPF_ATTACH_TYPE }; diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 1354bcbc8b30..1b09381d16ff 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -136,6 +136,8 @@ static const char * const attach_type_name[] = { [BPF_NETKIT_PEER] = "netkit_peer", [BPF_TRACE_KPROBE_SESSION] = "trace_kprobe_session", [BPF_TRACE_UPROBE_SESSION] = "trace_uprobe_session", + [BPF_TRACE_FENTRY_MULTI] = "trace_fentry_multi", + [BPF_TRACE_FEXIT_MULTI] = "trace_fexit_multi", }; static const char * const link_type_name[] = {