From patchwork Thu Apr 7 19:25:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kui-Feng Lee X-Patchwork-Id: 12805639 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 84F56C43217 for ; Thu, 7 Apr 2022 19:26:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231201AbiDGT2k (ORCPT ); Thu, 7 Apr 2022 15:28:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44722 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230418AbiDGT2e (ORCPT ); Thu, 7 Apr 2022 15:28:34 -0400 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ADF50286A6D for ; Thu, 7 Apr 2022 12:26:23 -0700 (PDT) Received: from pps.filterd (m0109331.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 237IB6tQ032676 for ; Thu, 7 Apr 2022 12:26:22 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=Q5OnuttxYilPhSNiorvU1VdHHYFILX+gj81JTtAj5SM=; b=OASqyH5Yd8zPqtaCit8ja4gsde/PWbVbAKlgRa5zfKqO7HP0cuG9woduWp9shdOPNRYf n4OpvipZr6+iunjsPrxnBUASVFJvyf9Pou/cs8pF9I6qJlxlnGVsdcpwWYW7eFTwg3D1 VF09JxvrNNHmdVd3nZNJkVyQLzzMkoewgQo= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3f91ykeq5h-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 07 Apr 2022 12:26:22 -0700 Received: from twshared27284.14.frc2.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Thu, 7 Apr 2022 12:26:20 -0700 Received: by devbig931.frc1.facebook.com (Postfix, from userid 460691) id 9284B200EE7B; Thu, 7 Apr 2022 12:26:15 -0700 (PDT) From: Kui-Feng Lee To: , , , , CC: Kui-Feng Lee Subject: [PATCH bpf-next v3 1/5] bpf, x86: Generate trampolines from bpf_tramp_links Date: Thu, 7 Apr 2022 12:25:48 -0700 Message-ID: <20220407192552.2343076-2-kuifeng@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220407192552.2343076-1-kuifeng@fb.com> References: <20220407192552.2343076-1-kuifeng@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-ORIG-GUID: dqEllzjMf_ba9NNtEzbfj89dXmtZvGqt X-Proofpoint-GUID: dqEllzjMf_ba9NNtEzbfj89dXmtZvGqt X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.425,FMLib:17.11.64.514 definitions=2022-04-07_04,2022-04-07_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Replace struct bpf_tramp_progs with struct bpf_tramp_links to collect struct bpf_tramp_link(s) for a trampoline. struct bpf_tramp_link extends bpf_link to act as a linked list node. arch_prepare_bpf_trampoline() accepts a struct bpf_tramp_links to collects all bpf_tramp_link(s) that a trampoline should call. Change BPF trampoline and bpf_struct_ops to pass bpf_tramp_links instead of bpf_tramp_progs. Signed-off-by: Kui-Feng Lee --- arch/x86/net/bpf_jit_comp.c | 36 +++++++++-------- include/linux/bpf.h | 38 ++++++++++++------ include/linux/bpf_types.h | 1 + include/uapi/linux/bpf.h | 1 + kernel/bpf/bpf_struct_ops.c | 69 ++++++++++++++++++++++---------- kernel/bpf/syscall.c | 23 ++++------- kernel/bpf/trampoline.c | 73 +++++++++++++++++++--------------- net/bpf/bpf_dummy_struct_ops.c | 35 +++++++++++++--- tools/bpf/bpftool/link.c | 1 + tools/include/uapi/linux/bpf.h | 1 + 10 files changed, 175 insertions(+), 103 deletions(-) diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index e6ff8f4f9ea4..8a1720988996 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1743,10 +1743,12 @@ static void restore_regs(const struct btf_func_model *m, u8 **prog, int nr_args, } static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog, - struct bpf_prog *p, int stack_size, bool save_ret) + struct bpf_tramp_link *l, int stack_size, + bool save_ret) { u8 *prog = *pprog; u8 *jmp_insn; + struct bpf_prog *p = l->link.prog; /* arg1: mov rdi, progs[i] */ emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, (u32) (long) p); @@ -1831,14 +1833,14 @@ static int emit_cond_near_jump(u8 **pprog, void *func, void *ip, u8 jmp_cond) } static int invoke_bpf(const struct btf_func_model *m, u8 **pprog, - struct bpf_tramp_progs *tp, int stack_size, + struct bpf_tramp_links *tl, int stack_size, bool save_ret) { int i; u8 *prog = *pprog; - for (i = 0; i < tp->nr_progs; i++) { - if (invoke_bpf_prog(m, &prog, tp->progs[i], stack_size, + for (i = 0; i < tl->nr_links; i++) { + if (invoke_bpf_prog(m, &prog, tl->links[i], stack_size, save_ret)) return -EINVAL; } @@ -1847,7 +1849,7 @@ static int invoke_bpf(const struct btf_func_model *m, u8 **pprog, } static int invoke_bpf_mod_ret(const struct btf_func_model *m, u8 **pprog, - struct bpf_tramp_progs *tp, int stack_size, + struct bpf_tramp_links *tl, int stack_size, u8 **branches) { u8 *prog = *pprog; @@ -1858,8 +1860,8 @@ static int invoke_bpf_mod_ret(const struct btf_func_model *m, u8 **pprog, */ emit_mov_imm32(&prog, false, BPF_REG_0, 0); emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8); - for (i = 0; i < tp->nr_progs; i++) { - if (invoke_bpf_prog(m, &prog, tp->progs[i], stack_size, true)) + for (i = 0; i < tl->nr_links; i++) { + if (invoke_bpf_prog(m, &prog, tl->links[i], stack_size, true)) return -EINVAL; /* mod_ret prog stored return value into [rbp - 8]. Emit: @@ -1961,14 +1963,14 @@ static bool is_valid_bpf_tramp_flags(unsigned int flags) */ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *image_end, const struct btf_func_model *m, u32 flags, - struct bpf_tramp_progs *tprogs, + struct bpf_tramp_links *tlinks, void *orig_call) { int ret, i, nr_args = m->nr_args; int regs_off, ip_off, args_off, stack_size = nr_args * 8; - struct bpf_tramp_progs *fentry = &tprogs[BPF_TRAMP_FENTRY]; - struct bpf_tramp_progs *fexit = &tprogs[BPF_TRAMP_FEXIT]; - struct bpf_tramp_progs *fmod_ret = &tprogs[BPF_TRAMP_MODIFY_RETURN]; + struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY]; + struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT]; + struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN]; u8 **branches = NULL; u8 *prog; bool save_ret; @@ -2055,13 +2057,13 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i } } - if (fentry->nr_progs) + if (fentry->nr_links) if (invoke_bpf(m, &prog, fentry, regs_off, flags & BPF_TRAMP_F_RET_FENTRY_RET)) return -EINVAL; - if (fmod_ret->nr_progs) { - branches = kcalloc(fmod_ret->nr_progs, sizeof(u8 *), + if (fmod_ret->nr_links) { + branches = kcalloc(fmod_ret->nr_links, sizeof(u8 *), GFP_KERNEL); if (!branches) return -ENOMEM; @@ -2088,7 +2090,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i prog += X86_PATCH_SIZE; } - if (fmod_ret->nr_progs) { + if (fmod_ret->nr_links) { /* From Intel 64 and IA-32 Architectures Optimization * Reference Manual, 3.4.1.4 Code Alignment, Assembly/Compiler * Coding Rule 11: All branch targets should be 16-byte @@ -2098,12 +2100,12 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i /* Update the branches saved in invoke_bpf_mod_ret with the * aligned address of do_fexit. */ - for (i = 0; i < fmod_ret->nr_progs; i++) + for (i = 0; i < fmod_ret->nr_links; i++) emit_cond_near_jump(&branches[i], prog, branches[i], X86_JNE); } - if (fexit->nr_progs) + if (fexit->nr_links) if (invoke_bpf(m, &prog, fexit, regs_off, false)) { ret = -EINVAL; goto cleanup; diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 88449fbbe063..c4b8ca17024b 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -674,11 +674,11 @@ struct btf_func_model { /* Each call __bpf_prog_enter + call bpf_func + call __bpf_prog_exit is ~50 * bytes on x86. Pick a number to fit into BPF_IMAGE_SIZE / 2 */ -#define BPF_MAX_TRAMP_PROGS 38 +#define BPF_MAX_TRAMP_LINKS 38 -struct bpf_tramp_progs { - struct bpf_prog *progs[BPF_MAX_TRAMP_PROGS]; - int nr_progs; +struct bpf_tramp_links { + struct bpf_tramp_link *links[BPF_MAX_TRAMP_LINKS]; + int nr_links; }; /* Different use cases for BPF trampoline: @@ -704,7 +704,7 @@ struct bpf_tramp_progs { struct bpf_tramp_image; int arch_prepare_bpf_trampoline(struct bpf_tramp_image *tr, void *image, void *image_end, const struct btf_func_model *m, u32 flags, - struct bpf_tramp_progs *tprogs, + struct bpf_tramp_links *tlinks, void *orig_call); /* these two functions are called from generated trampoline */ u64 notrace __bpf_prog_enter(struct bpf_prog *prog); @@ -803,9 +803,12 @@ static __always_inline __nocfi unsigned int bpf_dispatcher_nop_func( { return bpf_func(ctx, insnsi); } + +struct bpf_link; + #ifdef CONFIG_BPF_JIT -int bpf_trampoline_link_prog(struct bpf_prog *prog, struct bpf_trampoline *tr); -int bpf_trampoline_unlink_prog(struct bpf_prog *prog, struct bpf_trampoline *tr); +int bpf_trampoline_link_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr); +int bpf_trampoline_unlink_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr); struct bpf_trampoline *bpf_trampoline_get(u64 key, struct bpf_attach_target_info *tgt_info); void bpf_trampoline_put(struct bpf_trampoline *tr); @@ -856,12 +859,12 @@ int bpf_jit_charge_modmem(u32 size); void bpf_jit_uncharge_modmem(u32 size); bool bpf_prog_has_trampoline(const struct bpf_prog *prog); #else -static inline int bpf_trampoline_link_prog(struct bpf_prog *prog, +static inline int bpf_trampoline_link_prog(struct bpf_link *link, struct bpf_trampoline *tr) { return -ENOTSUPP; } -static inline int bpf_trampoline_unlink_prog(struct bpf_prog *prog, +static inline int bpf_trampoline_unlink_prog(struct bpf_link *link, struct bpf_trampoline *tr) { return -ENOTSUPP; @@ -960,7 +963,6 @@ struct bpf_prog_aux { bool tail_call_reachable; bool xdp_has_frags; bool use_bpf_prog_pack; - struct hlist_node tramp_hlist; /* BTF_KIND_FUNC_PROTO for valid attach_btf_id */ const struct btf_type *attach_func_proto; /* function name for valid attach_btf_id */ @@ -1047,6 +1049,18 @@ struct bpf_link_ops { struct bpf_link_info *info); }; +struct bpf_tramp_link { + struct bpf_link link; + struct hlist_node tramp_hlist; +}; + +struct bpf_tracing_link { + struct bpf_tramp_link link; + enum bpf_attach_type attach_type; + struct bpf_trampoline *trampoline; + struct bpf_prog *tgt_prog; +}; + struct bpf_link_primer { struct bpf_link *link; struct file *file; @@ -1084,8 +1098,8 @@ bool bpf_struct_ops_get(const void *kdata); void bpf_struct_ops_put(const void *kdata); int bpf_struct_ops_map_sys_lookup_elem(struct bpf_map *map, void *key, void *value); -int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_progs *tprogs, - struct bpf_prog *prog, +int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_links *tlinks, + struct bpf_tramp_link *link, const struct btf_func_model *model, void *image, void *image_end); static inline bool bpf_try_module_get(const void *data, struct module *owner) diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h index 48a91c51c015..8228c86eb92b 100644 --- a/include/linux/bpf_types.h +++ b/include/linux/bpf_types.h @@ -140,3 +140,4 @@ BPF_LINK_TYPE(BPF_LINK_TYPE_XDP, xdp) #ifdef CONFIG_PERF_EVENTS BPF_LINK_TYPE(BPF_LINK_TYPE_PERF_EVENT, perf) #endif +BPF_LINK_TYPE(BPF_LINK_TYPE_STRUCT_OPS, struct_ops) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 99fab54ae9c0..9e34da50440c 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1011,6 +1011,7 @@ enum bpf_link_type { BPF_LINK_TYPE_NETNS = 5, BPF_LINK_TYPE_XDP = 6, BPF_LINK_TYPE_PERF_EVENT = 7, + BPF_LINK_TYPE_STRUCT_OPS = 8, MAX_BPF_LINK_TYPE, }; diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c index 21069dbe9138..6aaaec69ec54 100644 --- a/kernel/bpf/bpf_struct_ops.c +++ b/kernel/bpf/bpf_struct_ops.c @@ -32,15 +32,15 @@ struct bpf_struct_ops_map { const struct bpf_struct_ops *st_ops; /* protect map_update */ struct mutex lock; - /* progs has all the bpf_prog that is populated + /* link has all the bpf_links that is populated * to the func ptr of the kernel's struct * (in kvalue.data). */ - struct bpf_prog **progs; + struct bpf_link **links; /* image is a page that has all the trampolines * that stores the func args before calling the bpf_prog. * A PAGE_SIZE "image" is enough to store all trampoline for - * "progs[]". + * "links[]". */ void *image; /* uvalue->data stores the kernel struct @@ -282,9 +282,9 @@ static void bpf_struct_ops_map_put_progs(struct bpf_struct_ops_map *st_map) u32 i; for (i = 0; i < btf_type_vlen(t); i++) { - if (st_map->progs[i]) { - bpf_prog_put(st_map->progs[i]); - st_map->progs[i] = NULL; + if (st_map->links[i]) { + bpf_link_put(st_map->links[i]); + st_map->links[i] = NULL; } } } @@ -315,18 +315,32 @@ static int check_zero_holes(const struct btf_type *t, void *data) return 0; } -int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_progs *tprogs, - struct bpf_prog *prog, +static void bpf_struct_ops_link_release(struct bpf_link *link) +{ +} + +static void bpf_struct_ops_link_dealloc(struct bpf_link *link) +{ + kfree(link); +} + +static const struct bpf_link_ops bpf_struct_ops_link_lops = { + .release = bpf_struct_ops_link_release, + .dealloc = bpf_struct_ops_link_dealloc, +}; + +int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_links *tlinks, + struct bpf_tramp_link *link, const struct btf_func_model *model, void *image, void *image_end) { u32 flags; - tprogs[BPF_TRAMP_FENTRY].progs[0] = prog; - tprogs[BPF_TRAMP_FENTRY].nr_progs = 1; + tlinks[BPF_TRAMP_FENTRY].links[0] = link; + tlinks[BPF_TRAMP_FENTRY].nr_links = 1; flags = model->ret_size > 0 ? BPF_TRAMP_F_RET_FENTRY_RET : 0; return arch_prepare_bpf_trampoline(NULL, image, image_end, - model, flags, tprogs, NULL); + model, flags, tlinks, NULL); } static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, @@ -337,7 +351,7 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, struct bpf_struct_ops_value *uvalue, *kvalue; const struct btf_member *member; const struct btf_type *t = st_ops->type; - struct bpf_tramp_progs *tprogs = NULL; + struct bpf_tramp_links *tlinks = NULL; void *udata, *kdata; int prog_fd, err = 0; void *image, *image_end; @@ -361,8 +375,8 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, if (uvalue->state || refcount_read(&uvalue->refcnt)) return -EINVAL; - tprogs = kcalloc(BPF_TRAMP_MAX, sizeof(*tprogs), GFP_KERNEL); - if (!tprogs) + tlinks = kcalloc(BPF_TRAMP_MAX, sizeof(*tlinks), GFP_KERNEL); + if (!tlinks) return -ENOMEM; uvalue = (struct bpf_struct_ops_value *)st_map->uvalue; @@ -385,6 +399,7 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, for_each_member(i, t, member) { const struct btf_type *mtype, *ptype; struct bpf_prog *prog; + struct bpf_tramp_link *link; u32 moff; moff = __btf_member_bit_offset(t, member) / 8; @@ -438,16 +453,26 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, err = PTR_ERR(prog); goto reset_unlock; } - st_map->progs[i] = prog; if (prog->type != BPF_PROG_TYPE_STRUCT_OPS || prog->aux->attach_btf_id != st_ops->type_id || prog->expected_attach_type != i) { + bpf_prog_put(prog); err = -EINVAL; goto reset_unlock; } - err = bpf_struct_ops_prepare_trampoline(tprogs, prog, + link = kzalloc(sizeof(*link), GFP_USER); + if (!link) { + bpf_prog_put(prog); + err = -ENOMEM; + goto reset_unlock; + } + bpf_link_init(&link->link, BPF_LINK_TYPE_STRUCT_OPS, + &bpf_struct_ops_link_lops, prog); + st_map->links[i] = &link->link; + + err = bpf_struct_ops_prepare_trampoline(tlinks, link, &st_ops->func_models[i], image, image_end); if (err < 0) @@ -490,7 +515,7 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, memset(uvalue, 0, map->value_size); memset(kvalue, 0, map->value_size); unlock: - kfree(tprogs); + kfree(tlinks); mutex_unlock(&st_map->lock); return err; } @@ -545,9 +570,9 @@ static void bpf_struct_ops_map_free(struct bpf_map *map) { struct bpf_struct_ops_map *st_map = (struct bpf_struct_ops_map *)map; - if (st_map->progs) + if (st_map->links) bpf_struct_ops_map_put_progs(st_map); - bpf_map_area_free(st_map->progs); + bpf_map_area_free(st_map->links); bpf_jit_free_exec(st_map->image); bpf_map_area_free(st_map->uvalue); bpf_map_area_free(st_map); @@ -596,11 +621,11 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr) map = &st_map->map; st_map->uvalue = bpf_map_area_alloc(vt->size, NUMA_NO_NODE); - st_map->progs = - bpf_map_area_alloc(btf_type_vlen(t) * sizeof(struct bpf_prog *), + st_map->links = + bpf_map_area_alloc(btf_type_vlen(t) * sizeof(struct bpf_links *), NUMA_NO_NODE); st_map->image = bpf_jit_alloc_exec(PAGE_SIZE); - if (!st_map->uvalue || !st_map->progs || !st_map->image) { + if (!st_map->uvalue || !st_map->links || !st_map->image) { bpf_struct_ops_map_free(map); return ERR_PTR(-ENOMEM); } diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 9beb585be5a6..dcd285929cf3 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2639,19 +2639,12 @@ struct bpf_link *bpf_link_get_from_fd(u32 ufd) } EXPORT_SYMBOL(bpf_link_get_from_fd); -struct bpf_tracing_link { - struct bpf_link link; - enum bpf_attach_type attach_type; - struct bpf_trampoline *trampoline; - struct bpf_prog *tgt_prog; -}; - static void bpf_tracing_link_release(struct bpf_link *link) { struct bpf_tracing_link *tr_link = - container_of(link, struct bpf_tracing_link, link); + container_of(link, struct bpf_tracing_link, link.link); - WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog, + WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link, tr_link->trampoline)); bpf_trampoline_put(tr_link->trampoline); @@ -2664,7 +2657,7 @@ static void bpf_tracing_link_release(struct bpf_link *link) static void bpf_tracing_link_dealloc(struct bpf_link *link) { struct bpf_tracing_link *tr_link = - container_of(link, struct bpf_tracing_link, link); + container_of(link, struct bpf_tracing_link, link.link); kfree(tr_link); } @@ -2673,7 +2666,7 @@ static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, struct seq_file *seq) { struct bpf_tracing_link *tr_link = - container_of(link, struct bpf_tracing_link, link); + container_of(link, struct bpf_tracing_link, link.link); seq_printf(seq, "attach_type:\t%d\n", @@ -2684,7 +2677,7 @@ static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, struct bpf_link_info *info) { struct bpf_tracing_link *tr_link = - container_of(link, struct bpf_tracing_link, link); + container_of(link, struct bpf_tracing_link, link.link); info->tracing.attach_type = tr_link->attach_type; bpf_trampoline_unpack_key(tr_link->trampoline->key, @@ -2765,7 +2758,7 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, err = -ENOMEM; goto out_put_prog; } - bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING, + bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING, &bpf_tracing_link_lops, prog); link->attach_type = prog->expected_attach_type; @@ -2835,11 +2828,11 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, tgt_prog = prog->aux->dst_prog; } - err = bpf_link_prime(&link->link, &link_primer); + err = bpf_link_prime(&link->link.link, &link_primer); if (err) goto out_unlock; - err = bpf_trampoline_link_prog(prog, tr); + err = bpf_trampoline_link_prog(&link->link, tr); if (err) { bpf_link_cleanup(&link_primer); link = NULL; diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index 0b41fa993825..5916f1da059d 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -180,30 +180,30 @@ static int register_fentry(struct bpf_trampoline *tr, void *new_addr) return ret; } -static struct bpf_tramp_progs * +static struct bpf_tramp_links * bpf_trampoline_get_progs(const struct bpf_trampoline *tr, int *total, bool *ip_arg) { - const struct bpf_prog_aux *aux; - struct bpf_tramp_progs *tprogs; - struct bpf_prog **progs; + struct bpf_tramp_link *link; + struct bpf_tramp_links *tlinks; + struct bpf_tramp_link **links; int kind; *total = 0; - tprogs = kcalloc(BPF_TRAMP_MAX, sizeof(*tprogs), GFP_KERNEL); - if (!tprogs) + tlinks = kcalloc(BPF_TRAMP_MAX, sizeof(*tlinks), GFP_KERNEL); + if (!tlinks) return ERR_PTR(-ENOMEM); for (kind = 0; kind < BPF_TRAMP_MAX; kind++) { - tprogs[kind].nr_progs = tr->progs_cnt[kind]; + tlinks[kind].nr_links = tr->progs_cnt[kind]; *total += tr->progs_cnt[kind]; - progs = tprogs[kind].progs; + links = tlinks[kind].links; - hlist_for_each_entry(aux, &tr->progs_hlist[kind], tramp_hlist) { - *ip_arg |= aux->prog->call_get_func_ip; - *progs++ = aux->prog; + hlist_for_each_entry(link, &tr->progs_hlist[kind], tramp_hlist) { + *ip_arg |= link->link.prog->call_get_func_ip; + *links++ = link; } } - return tprogs; + return tlinks; } static void __bpf_tramp_image_put_deferred(struct work_struct *work) @@ -342,14 +342,14 @@ static struct bpf_tramp_image *bpf_tramp_image_alloc(u64 key, u32 idx) static int bpf_trampoline_update(struct bpf_trampoline *tr) { struct bpf_tramp_image *im; - struct bpf_tramp_progs *tprogs; + struct bpf_tramp_links *tlinks; u32 flags = BPF_TRAMP_F_RESTORE_REGS; bool ip_arg = false; int err, total; - tprogs = bpf_trampoline_get_progs(tr, &total, &ip_arg); - if (IS_ERR(tprogs)) - return PTR_ERR(tprogs); + tlinks = bpf_trampoline_get_progs(tr, &total, &ip_arg); + if (IS_ERR(tlinks)) + return PTR_ERR(tlinks); if (total == 0) { err = unregister_fentry(tr, tr->cur_image->image); @@ -365,15 +365,15 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr) goto out; } - if (tprogs[BPF_TRAMP_FEXIT].nr_progs || - tprogs[BPF_TRAMP_MODIFY_RETURN].nr_progs) + if (tlinks[BPF_TRAMP_FEXIT].nr_links || + tlinks[BPF_TRAMP_MODIFY_RETURN].nr_links) flags = BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_SKIP_FRAME; if (ip_arg) flags |= BPF_TRAMP_F_IP_ARG; err = arch_prepare_bpf_trampoline(im, im->image, im->image + PAGE_SIZE, - &tr->func.model, flags, tprogs, + &tr->func.model, flags, tlinks, tr->func.addr); if (err < 0) goto out; @@ -393,7 +393,7 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr) tr->cur_image = im; tr->selector++; out: - kfree(tprogs); + kfree(tlinks); return err; } @@ -419,13 +419,14 @@ static enum bpf_tramp_prog_type bpf_attach_type_to_tramp(struct bpf_prog *prog) } } -int bpf_trampoline_link_prog(struct bpf_prog *prog, struct bpf_trampoline *tr) +int bpf_trampoline_link_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr) { enum bpf_tramp_prog_type kind; + struct bpf_tramp_link *link_exiting; int err = 0; int cnt; - kind = bpf_attach_type_to_tramp(prog); + kind = bpf_attach_type_to_tramp(link->link.prog); mutex_lock(&tr->mutex); if (tr->extension_prog) { /* cannot attach fentry/fexit if extension prog is attached. @@ -441,25 +442,33 @@ int bpf_trampoline_link_prog(struct bpf_prog *prog, struct bpf_trampoline *tr) err = -EBUSY; goto out; } - tr->extension_prog = prog; + tr->extension_prog = link->link.prog; err = bpf_arch_text_poke(tr->func.addr, BPF_MOD_JUMP, NULL, - prog->bpf_func); + link->link.prog->bpf_func); goto out; } - if (cnt >= BPF_MAX_TRAMP_PROGS) { + if (cnt >= BPF_MAX_TRAMP_LINKS) { err = -E2BIG; goto out; } - if (!hlist_unhashed(&prog->aux->tramp_hlist)) { + if (!hlist_unhashed(&link->tramp_hlist)) { /* prog already linked */ err = -EBUSY; goto out; } - hlist_add_head(&prog->aux->tramp_hlist, &tr->progs_hlist[kind]); + hlist_for_each_entry(link_exiting, &tr->progs_hlist[kind], tramp_hlist) { + if (link_exiting->link.prog != link->link.prog) + continue; + /* prog already linked */ + err = -EBUSY; + goto out; + } + + hlist_add_head(&link->tramp_hlist, &tr->progs_hlist[kind]); tr->progs_cnt[kind]++; err = bpf_trampoline_update(tr); if (err) { - hlist_del_init(&prog->aux->tramp_hlist); + hlist_del_init(&link->tramp_hlist); tr->progs_cnt[kind]--; } out: @@ -468,12 +477,12 @@ int bpf_trampoline_link_prog(struct bpf_prog *prog, struct bpf_trampoline *tr) } /* bpf_trampoline_unlink_prog() should never fail. */ -int bpf_trampoline_unlink_prog(struct bpf_prog *prog, struct bpf_trampoline *tr) +int bpf_trampoline_unlink_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr) { enum bpf_tramp_prog_type kind; int err; - kind = bpf_attach_type_to_tramp(prog); + kind = bpf_attach_type_to_tramp(link->link.prog); mutex_lock(&tr->mutex); if (kind == BPF_TRAMP_REPLACE) { WARN_ON_ONCE(!tr->extension_prog); @@ -482,7 +491,7 @@ int bpf_trampoline_unlink_prog(struct bpf_prog *prog, struct bpf_trampoline *tr) tr->extension_prog = NULL; goto out; } - hlist_del_init(&prog->aux->tramp_hlist); + hlist_del_init(&link->tramp_hlist); tr->progs_cnt[kind]--; err = bpf_trampoline_update(tr); out: @@ -647,7 +656,7 @@ void notrace __bpf_tramp_exit(struct bpf_tramp_image *tr) int __weak arch_prepare_bpf_trampoline(struct bpf_tramp_image *tr, void *image, void *image_end, const struct btf_func_model *m, u32 flags, - struct bpf_tramp_progs *tprogs, + struct bpf_tramp_links *tlinks, void *orig_call) { return -ENOTSUPP; diff --git a/net/bpf/bpf_dummy_struct_ops.c b/net/bpf/bpf_dummy_struct_ops.c index d0e54e30658a..b3717f3ab44b 100644 --- a/net/bpf/bpf_dummy_struct_ops.c +++ b/net/bpf/bpf_dummy_struct_ops.c @@ -72,13 +72,28 @@ static int dummy_ops_call_op(void *image, struct bpf_dummy_ops_test_args *args) args->args[3], args->args[4]); } +static void bpf_struct_ops_link_release(struct bpf_link *link) +{ +} + +static void bpf_struct_ops_link_dealloc(struct bpf_link *link) +{ + kfree(link); +} + +static const struct bpf_link_ops bpf_struct_ops_link_lops = { + .release = bpf_struct_ops_link_release, + .dealloc = bpf_struct_ops_link_dealloc, +}; + int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, union bpf_attr __user *uattr) { const struct bpf_struct_ops *st_ops = &bpf_bpf_dummy_ops; const struct btf_type *func_proto; struct bpf_dummy_ops_test_args *args; - struct bpf_tramp_progs *tprogs; + struct bpf_tramp_links *tlinks; + struct bpf_tramp_link *link = NULL; void *image = NULL; unsigned int op_idx; int prog_ret; @@ -92,8 +107,8 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, if (IS_ERR(args)) return PTR_ERR(args); - tprogs = kcalloc(BPF_TRAMP_MAX, sizeof(*tprogs), GFP_KERNEL); - if (!tprogs) { + tlinks = kcalloc(BPF_TRAMP_MAX, sizeof(*tlinks), GFP_KERNEL); + if (!tlinks) { err = -ENOMEM; goto out; } @@ -105,10 +120,18 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, } set_vm_flush_reset_perms(image); + link = kzalloc(sizeof(*link), GFP_USER); + if (!link) { + err = -ENOMEM; + goto out; + } + bpf_link_init(&link->link, BPF_LINK_TYPE_STRUCT_OPS, &bpf_struct_ops_link_lops, prog); + op_idx = prog->expected_attach_type; - err = bpf_struct_ops_prepare_trampoline(tprogs, prog, + err = bpf_struct_ops_prepare_trampoline(tlinks, link, &st_ops->func_models[op_idx], image, image + PAGE_SIZE); + if (err < 0) goto out; @@ -124,7 +147,9 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr, out: kfree(args); bpf_jit_free_exec(image); - kfree(tprogs); + if (link) + bpf_link_put(&link->link); + kfree(tlinks); return err; } diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c index 97dec81950e5..d49a2bdc983f 100644 --- a/tools/bpf/bpftool/link.c +++ b/tools/bpf/bpftool/link.c @@ -20,6 +20,7 @@ static const char * const link_type_name[] = { [BPF_LINK_TYPE_CGROUP] = "cgroup", [BPF_LINK_TYPE_ITER] = "iter", [BPF_LINK_TYPE_NETNS] = "netns", + [BPF_LINK_TYPE_STRUCT_OPS] = "struct_ops", }; static struct hashmap *link_table; diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 99fab54ae9c0..9e34da50440c 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1011,6 +1011,7 @@ enum bpf_link_type { BPF_LINK_TYPE_NETNS = 5, BPF_LINK_TYPE_XDP = 6, BPF_LINK_TYPE_PERF_EVENT = 7, + BPF_LINK_TYPE_STRUCT_OPS = 8, MAX_BPF_LINK_TYPE, }; From patchwork Thu Apr 7 19:25:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kui-Feng Lee X-Patchwork-Id: 12805640 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8510DC433F5 for ; Thu, 7 Apr 2022 19:26:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230418AbiDGT2l (ORCPT ); Thu, 7 Apr 2022 15:28:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231181AbiDGT2f (ORCPT ); Thu, 7 Apr 2022 15:28:35 -0400 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1ECA1283F72 for ; Thu, 7 Apr 2022 12:26:26 -0700 (PDT) Received: from pps.filterd (m0148461.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 237IAlGb012424 for ; Thu, 7 Apr 2022 12:26:26 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=aOMVzypwbM4melWUvSKDDONw6wyDrfXWldHE9ItHZng=; b=S8faRPJL+yxSKBuErv8TFqJpYv082LKtb3Aq5x/D9F2m3i0HzbD+SU52trwvXy7bD4jo RtnMZO+esoXDV5AAyqIRibuGYMsc+XfwGZB6Pv9gKdpVKIanSO6F675xel1phC0Z90P/ JHn6xv8QPAgnxVw1tYHDR5S4JTfCO+ESMJo= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3f9gmr0yxt-3 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 07 Apr 2022 12:26:26 -0700 Received: from twshared39027.37.frc1.facebook.com (2620:10d:c085:108::8) by mail.thefacebook.com (2620:10d:c085:21d::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Thu, 7 Apr 2022 12:26:24 -0700 Received: by devbig931.frc1.facebook.com (Postfix, from userid 460691) id 28BB4200EE7F; Thu, 7 Apr 2022 12:26:17 -0700 (PDT) From: Kui-Feng Lee To: , , , , CC: Kui-Feng Lee Subject: [PATCH bpf-next v3 2/5] bpf, x86: Create bpf_tramp_run_ctx on the caller thread's stack Date: Thu, 7 Apr 2022 12:25:49 -0700 Message-ID: <20220407192552.2343076-3-kuifeng@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220407192552.2343076-1-kuifeng@fb.com> References: <20220407192552.2343076-1-kuifeng@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-ORIG-GUID: DYNGZz4LnPV5RJD3iPtZVYjS5T4w0j4_ X-Proofpoint-GUID: DYNGZz4LnPV5RJD3iPtZVYjS5T4w0j4_ X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.425,FMLib:17.11.64.514 definitions=2022-04-07_04,2022-04-07_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net BPF trampolines will create a bpf_tramp_run_ctx, a bpf_run_ctx, on stacks and set/reset the current bpf_run_ctx before/after calling a bpf_prog. Signed-off-by: Kui-Feng Lee --- arch/x86/net/bpf_jit_comp.c | 55 +++++++++++++++++++++++++++++++++++++ include/linux/bpf.h | 17 +++++++++--- kernel/bpf/syscall.c | 4 +-- kernel/bpf/trampoline.c | 23 +++++++++++++--- 4 files changed, 89 insertions(+), 10 deletions(-) diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 8a1720988996..61b72d537f5b 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1748,10 +1748,26 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog, { u8 *prog = *pprog; u8 *jmp_insn; + int ctx_cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie); struct bpf_prog *p = l->link.prog; + /* mov rdi, 0 */ + emit_mov_imm64(&prog, BPF_REG_1, 0, 0); + + /* Prepare struct bpf_tramp_run_ctx. + * + * bpf_tramp_run_ctx is already preserved by + * arch_prepare_bpf_trampoline(). + * + * mov QWORD PTR [rsp + ctx_cookie_off], rdi + */ + EMIT4(0x48, 0x89, 0x7C, 0x24); EMIT1(ctx_cookie_off); + /* arg1: mov rdi, progs[i] */ emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, (u32) (long) p); + /* arg2: mov rsi, rsp (struct bpf_run_ctx *) */ + EMIT3(0x48, 0x89, 0xE6); + if (emit_call(&prog, p->aux->sleepable ? __bpf_prog_enter_sleepable : __bpf_prog_enter, prog)) @@ -1797,6 +1813,8 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog, emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, (u32) (long) p); /* arg2: mov rsi, rbx <- start time in nsec */ emit_mov_reg(&prog, true, BPF_REG_2, BPF_REG_6); + /* arg3: mov rdx, rsp (struct bpf_run_ctx *) */ + EMIT3(0x48, 0x89, 0xE2); if (emit_call(&prog, p->aux->sleepable ? __bpf_prog_exit_sleepable : __bpf_prog_exit, prog)) @@ -2057,6 +2075,16 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i } } + if (nr_args < 3 && (fentry->nr_links || fexit->nr_links || fmod_ret->nr_links)) + EMIT1(0x52); /* push rdx */ + + if (fentry->nr_links || fexit->nr_links || fmod_ret->nr_links) { + /* Prepare struct bpf_tramp_run_ctx. + * sub rsp, sizeof(struct bpf_tramp_run_ctx) + */ + EMIT4(0x48, 0x83, 0xEC, sizeof(struct bpf_tramp_run_ctx)); + } + if (fentry->nr_links) if (invoke_bpf(m, &prog, fentry, regs_off, flags & BPF_TRAMP_F_RET_FENTRY_RET)) @@ -2076,6 +2104,15 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i } if (flags & BPF_TRAMP_F_CALL_ORIG) { + /* pop struct bpf_tramp_run_ctx + * add rsp, sizeof(struct bpf_tramp_run_ctx) + */ + if (fentry->nr_links || fexit->nr_links || fmod_ret->nr_links) + EMIT4(0x48, 0x83, 0xC4, sizeof(struct bpf_tramp_run_ctx)); + + if (nr_args < 3 && (fentry->nr_links || fexit->nr_links || fmod_ret->nr_links)) + EMIT1(0x5A); /* pop rdx */ + restore_regs(m, &prog, nr_args, regs_off); /* call original function */ @@ -2088,6 +2125,15 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i im->ip_after_call = prog; memcpy(prog, x86_nops[5], X86_PATCH_SIZE); prog += X86_PATCH_SIZE; + + if (nr_args < 3 && (fentry->nr_links || fexit->nr_links || fmod_ret->nr_links)) + EMIT1(0x52); /* push rdx */ + + /* Prepare struct bpf_tramp_run_ctx. + * sub rsp, sizeof(struct bpf_tramp_run_ctx) + */ + if (fentry->nr_links || fexit->nr_links || fmod_ret->nr_links) + EMIT4(0x48, 0x83, 0xEC, sizeof(struct bpf_tramp_run_ctx)); } if (fmod_ret->nr_links) { @@ -2111,6 +2157,15 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i goto cleanup; } + /* pop struct bpf_tramp_run_ctx + * add rsp, sizeof(struct bpf_tramp_run_ctx) + */ + if (fentry->nr_links || fexit->nr_links || fmod_ret->nr_links) + EMIT4(0x48, 0x83, 0xC4, sizeof(struct bpf_tramp_run_ctx)); + + if (nr_args < 3 && (fentry->nr_links || fexit->nr_links || fmod_ret->nr_links)) + EMIT1(0x5A); /* pop rdx */ + if (flags & BPF_TRAMP_F_RESTORE_REGS) restore_regs(m, &prog, nr_args, regs_off); diff --git a/include/linux/bpf.h b/include/linux/bpf.h index c4b8ca17024b..7b4896c86dcc 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -681,6 +681,8 @@ struct bpf_tramp_links { int nr_links; }; +struct bpf_tramp_run_ctx; + /* Different use cases for BPF trampoline: * 1. replace nop at the function entry (kprobe equivalent) * flags = BPF_TRAMP_F_RESTORE_REGS @@ -707,10 +709,11 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *tr, void *image, void *i struct bpf_tramp_links *tlinks, void *orig_call); /* these two functions are called from generated trampoline */ -u64 notrace __bpf_prog_enter(struct bpf_prog *prog); -void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start); -u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog); -void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start); +u64 notrace __bpf_prog_enter(struct bpf_prog *prog, struct bpf_tramp_run_ctx *run_ctx); +void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start, struct bpf_tramp_run_ctx *run_ctx); +u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog, struct bpf_tramp_run_ctx *run_ctx); +void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start, + struct bpf_tramp_run_ctx *run_ctx); void notrace __bpf_tramp_enter(struct bpf_tramp_image *tr); void notrace __bpf_tramp_exit(struct bpf_tramp_image *tr); @@ -1304,6 +1307,12 @@ struct bpf_trace_run_ctx { u64 bpf_cookie; }; +struct bpf_tramp_run_ctx { + struct bpf_run_ctx run_ctx; + u64 bpf_cookie; + struct bpf_run_ctx *saved_run_ctx; +}; + static inline struct bpf_run_ctx *bpf_set_run_ctx(struct bpf_run_ctx *new_ctx) { struct bpf_run_ctx *old_ctx = NULL; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index dcd285929cf3..12a1c0ff6646 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -4786,13 +4786,13 @@ BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size) return -EINVAL; } - if (!__bpf_prog_enter_sleepable(prog)) { + if (!__bpf_prog_enter_sleepable(prog, NULL)) { /* recursion detected */ bpf_prog_put(prog); return -EBUSY; } attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in); - __bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */); + __bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */, NULL); bpf_prog_put(prog); return 0; #endif diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index 5916f1da059d..a2971119ca10 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -580,11 +580,15 @@ static void notrace inc_misses_counter(struct bpf_prog *prog) * [2..MAX_U64] - execute bpf prog and record execution time. * This is start time. */ -u64 notrace __bpf_prog_enter(struct bpf_prog *prog) +u64 notrace __bpf_prog_enter(struct bpf_prog *prog, struct bpf_tramp_run_ctx *run_ctx) __acquires(RCU) { rcu_read_lock(); migrate_disable(); + + if (run_ctx) + run_ctx->saved_run_ctx = bpf_set_run_ctx(&run_ctx->run_ctx); + if (unlikely(__this_cpu_inc_return(*(prog->active)) != 1)) { inc_misses_counter(prog); return 0; @@ -614,20 +618,27 @@ static void notrace update_prog_stats(struct bpf_prog *prog, } } -void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start) +void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start, struct bpf_tramp_run_ctx *run_ctx) __releases(RCU) { + if (run_ctx) + bpf_reset_run_ctx(run_ctx->saved_run_ctx); + update_prog_stats(prog, start); __this_cpu_dec(*(prog->active)); migrate_enable(); rcu_read_unlock(); } -u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog) +u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog, struct bpf_tramp_run_ctx *run_ctx) { rcu_read_lock_trace(); migrate_disable(); might_fault(); + + if (run_ctx) + run_ctx->saved_run_ctx = bpf_set_run_ctx(&run_ctx->run_ctx); + if (unlikely(__this_cpu_inc_return(*(prog->active)) != 1)) { inc_misses_counter(prog); return 0; @@ -635,8 +646,12 @@ u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog) return bpf_prog_start_time(); } -void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start) +void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start, + struct bpf_tramp_run_ctx *run_ctx) { + if (run_ctx) + bpf_reset_run_ctx(run_ctx->saved_run_ctx); + update_prog_stats(prog, start); __this_cpu_dec(*(prog->active)); migrate_enable(); From patchwork Thu Apr 7 19:25:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kui-Feng Lee X-Patchwork-Id: 12805641 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CBAB2C433FE for ; Thu, 7 Apr 2022 19:26:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229977AbiDGT2m (ORCPT ); Thu, 7 Apr 2022 15:28:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45242 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230511AbiDGT2g (ORCPT ); Thu, 7 Apr 2022 15:28:36 -0400 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA933286F5A for ; Thu, 7 Apr 2022 12:26:27 -0700 (PDT) Received: from pps.filterd (m0148460.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 237IBBUf013988 for ; Thu, 7 Apr 2022 12:26:26 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=1rTbjcREWkItfaJXvnDq6PRV6naAgVQX0T6BqaCB1Dw=; b=ImF5dAQ49nqbU2vq4y3ILaVJQl+7g3J9rtGCHUtf5YJYkML8B1zggl1G1tn6WWXPIhLq bgs6yKJL2P70mAWxJyxhPdlfAnEmoXKEiKIvesCf3OuNK/M2sDXVQ34mvdxoISrGSnJ3 yNMQLQeDP4V4MEldn47Jrf20X8ksjAGM9jo= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3f9nrnen30-4 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 07 Apr 2022 12:26:26 -0700 Received: from twshared5730.23.frc3.facebook.com (2620:10d:c085:108::8) by mail.thefacebook.com (2620:10d:c085:11d::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Thu, 7 Apr 2022 12:26:24 -0700 Received: by devbig931.frc1.facebook.com (Postfix, from userid 460691) id 6FF63200EE85; Thu, 7 Apr 2022 12:26:18 -0700 (PDT) From: Kui-Feng Lee To: , , , , CC: Kui-Feng Lee Subject: [PATCH bpf-next v3 3/5] bpf, x86: Attach a cookie to fentry/fexit/fmod_ret. Date: Thu, 7 Apr 2022 12:25:50 -0700 Message-ID: <20220407192552.2343076-4-kuifeng@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220407192552.2343076-1-kuifeng@fb.com> References: <20220407192552.2343076-1-kuifeng@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-GUID: -rJn0efp5BWrNpp3ZNVT7ORI8u44-gyw X-Proofpoint-ORIG-GUID: -rJn0efp5BWrNpp3ZNVT7ORI8u44-gyw X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.425,FMLib:17.11.64.514 definitions=2022-04-07_04,2022-04-07_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Add a bpf_cookie field to struct bpf_tracing_link to attach a cookie to a link of a trace hook. A cookie of a bpf_tracing_link is available by calling bpf_get_attach_cookie when running the BPF program of the attached link. The value of a cookie will be set at bpf_tramp_run_ctx by the trampoline of the link. Signed-off-by: Kui-Feng Lee --- arch/x86/net/bpf_jit_comp.c | 11 +++++++++-- include/linux/bpf.h | 1 + include/uapi/linux/bpf.h | 8 ++++++++ kernel/bpf/syscall.c | 27 +++++++++++++++++++++++---- kernel/trace/bpf_trace.c | 17 +++++++++++++++++ tools/include/uapi/linux/bpf.h | 7 +++++++ 6 files changed, 65 insertions(+), 6 deletions(-) diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 61b72d537f5b..8d834f44efea 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1746,13 +1746,20 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog, struct bpf_tramp_link *l, int stack_size, bool save_ret) { + u64 cookie = 0; u8 *prog = *pprog; u8 *jmp_insn; int ctx_cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie); struct bpf_prog *p = l->link.prog; - /* mov rdi, 0 */ - emit_mov_imm64(&prog, BPF_REG_1, 0, 0); + if (l->link.type == BPF_LINK_TYPE_TRACING) { + struct bpf_tracing_link *tr_link = + container_of(l, struct bpf_tracing_link, link); + cookie = tr_link->cookie; + } + + /* mov rdi, cookie */ + emit_mov_imm64(&prog, BPF_REG_1, (long) cookie >> 32, (u32) (long) cookie); /* Prepare struct bpf_tramp_run_ctx. * diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 7b4896c86dcc..65a9b9c12a6c 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1062,6 +1062,7 @@ struct bpf_tracing_link { enum bpf_attach_type attach_type; struct bpf_trampoline *trampoline; struct bpf_prog *tgt_prog; + u64 cookie; }; struct bpf_link_primer { diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 9e34da50440c..9ccc77d93e97 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1429,6 +1429,7 @@ union bpf_attr { struct { /* anonymous struct used by BPF_RAW_TRACEPOINT_OPEN command */ __u64 name; __u32 prog_fd; + __u64 bpf_cookie; } raw_tracepoint; struct { /* anonymous struct for BPF_BTF_LOAD */ @@ -1476,6 +1477,13 @@ union bpf_attr { */ __u64 bpf_cookie; } perf_event; + struct { + /* black box user-provided value passed through + * to BPF program at the execution time and + * accessible through bpf_get_attach_cookie() BPF helper + */ + __u64 bpf_cookie; + } tracing; }; } link_create; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 12a1c0ff6646..84b3fe2d65d3 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2694,9 +2694,10 @@ static const struct bpf_link_ops bpf_tracing_link_lops = { .fill_link_info = bpf_tracing_link_fill_link_info, }; -static int bpf_tracing_prog_attach(struct bpf_prog *prog, - int tgt_prog_fd, - u32 btf_id) +static int bpf_tracing_prog_attach_cookie(struct bpf_prog *prog, + int tgt_prog_fd, + u32 btf_id, + u64 bpf_cookie) { struct bpf_link_primer link_primer; struct bpf_prog *tgt_prog = NULL; @@ -2761,6 +2762,7 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING, &bpf_tracing_link_lops, prog); link->attach_type = prog->expected_attach_type; + link->cookie = bpf_cookie; mutex_lock(&prog->aux->dst_mutex); @@ -2870,6 +2872,13 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, return err; } +static int bpf_tracing_prog_attach(struct bpf_prog *prog, + int tgt_prog_fd, + u32 btf_id) +{ + return bpf_tracing_prog_attach_cookie(prog, tgt_prog_fd, btf_id, 0); +} + struct bpf_raw_tp_link { struct bpf_link link; struct bpf_raw_event_map *btp; @@ -3017,7 +3026,7 @@ static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *pro } #endif /* CONFIG_PERF_EVENTS */ -#define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd +#define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.bpf_cookie static int bpf_raw_tracepoint_open(const union bpf_attr *attr) { @@ -3181,6 +3190,10 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type) return BPF_PROG_TYPE_SK_LOOKUP; case BPF_XDP: return BPF_PROG_TYPE_XDP; + case BPF_TRACE_FENTRY: + case BPF_TRACE_FEXIT: + case BPF_MODIFY_RETURN: + return BPF_PROG_TYPE_TRACING; default: return BPF_PROG_TYPE_UNSPEC; } @@ -4245,6 +4258,12 @@ static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr, return bpf_tracing_prog_attach(prog, attr->link_create.target_fd, attr->link_create.target_btf_id); + else if (prog->type == BPF_PROG_TYPE_TRACING) + return bpf_tracing_prog_attach_cookie(prog, + 0, + 0, + attr->link_create.tracing.bpf_cookie); + return -EINVAL; } diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index a2024ba32a20..1558b0476b3a 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -1063,6 +1063,21 @@ static const struct bpf_func_proto bpf_get_attach_cookie_proto_pe = { .arg1_type = ARG_PTR_TO_CTX, }; +BPF_CALL_1(bpf_get_attach_cookie_tracing, void *, ctx) +{ + struct bpf_trace_run_ctx *run_ctx; + + run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx); + return run_ctx->bpf_cookie; +} + +static const struct bpf_func_proto bpf_get_attach_cookie_proto_tracing = { + .func = bpf_get_attach_cookie_tracing, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, +}; + BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags) { #ifndef CONFIG_X86 @@ -1687,6 +1702,8 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL; case BPF_FUNC_get_func_arg_cnt: return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL; + case BPF_FUNC_get_attach_cookie: + return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto_tracing : NULL; default: fn = raw_tp_prog_func_proto(func_id, prog); if (!fn && prog->expected_attach_type == BPF_TRACE_ITER) diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 9e34da50440c..6c3e2f5a3474 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1476,6 +1476,13 @@ union bpf_attr { */ __u64 bpf_cookie; } perf_event; + struct { + /* black box user-provided value passed through + * to BPF program at the execution time and + * accessible through bpf_get_attach_cookie() BPF helper + */ + __u64 bpf_cookie; + } tracing; }; } link_create; From patchwork Thu Apr 7 19:25:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kui-Feng Lee X-Patchwork-Id: 12805642 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A2E7C433EF for ; Thu, 7 Apr 2022 19:26:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230042AbiDGT2o (ORCPT ); Thu, 7 Apr 2022 15:28:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230457AbiDGT2n (ORCPT ); Thu, 7 Apr 2022 15:28:43 -0400 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 720D4283F6A for ; Thu, 7 Apr 2022 12:26:33 -0700 (PDT) Received: from pps.filterd (m0109334.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 237IAgMG016907 for ; Thu, 7 Apr 2022 12:26:33 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=BV1oHiYsXQTJrzAg5b8dYwyiKTRryO0K3tsvF+2GCt8=; b=cX2rMlJ+35V6EfOdcd5SB92qPE/3sxU9iNMKfOMsZ6Nscmi80fqNDwLgJVRypR9dswd7 20uvs/25T0XE32TyHVDpih5ddAVH1LUJfoBVCpQPhuON3SkxQBavRTQsz65DSnNdHEED 13oaQvHhBoE4FMQWVhZStynpk7sECCDHHyM= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3f9q7fx3kk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 07 Apr 2022 12:26:32 -0700 Received: from twshared29473.14.frc2.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Thu, 7 Apr 2022 12:26:31 -0700 Received: by devbig931.frc1.facebook.com (Postfix, from userid 460691) id 1A842200EE89; Thu, 7 Apr 2022 12:26:23 -0700 (PDT) From: Kui-Feng Lee To: , , , , CC: Kui-Feng Lee Subject: [PATCH bpf-next v3 4/5] lib/bpf: Assign cookies to links in libbpf. Date: Thu, 7 Apr 2022 12:25:51 -0700 Message-ID: <20220407192552.2343076-5-kuifeng@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220407192552.2343076-1-kuifeng@fb.com> References: <20220407192552.2343076-1-kuifeng@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-ORIG-GUID: nYX5p2OhiyfZAFwxxww-cqNdUFx1KiHq X-Proofpoint-GUID: nYX5p2OhiyfZAFwxxww-cqNdUFx1KiHq X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.425,FMLib:17.11.64.514 definitions=2022-04-07_04,2022-04-07_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Add a cookie field to the attributes of bpf_link_create(). Add bpf_program__attach_trace_opts() to attach a cookie to a link. Signed-off-by: Kui-Feng Lee --- tools/lib/bpf/bpf.c | 7 +++++++ tools/lib/bpf/bpf.h | 3 +++ tools/lib/bpf/libbpf.c | 33 +++++++++++++++++++++++++++++++++ tools/lib/bpf/libbpf.h | 12 ++++++++++++ tools/lib/bpf/libbpf.map | 1 + 5 files changed, 56 insertions(+) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index f69ce3a01385..1586f2e87964 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -854,6 +854,13 @@ int bpf_link_create(int prog_fd, int target_fd, if (!OPTS_ZEROED(opts, perf_event)) return libbpf_err(-EINVAL); break; + case BPF_TRACE_FENTRY: + case BPF_TRACE_FEXIT: + case BPF_MODIFY_RETURN: + attr.link_create.tracing.bpf_cookie = OPTS_GET(opts, tracing.bpf_cookie, 0); + if (!OPTS_ZEROED(opts, tracing)) + return libbpf_err(-EINVAL); + break; default: if (!OPTS_ZEROED(opts, flags)) return libbpf_err(-EINVAL); diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 5253cb4a4c0a..e7df17277c8d 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -410,6 +410,9 @@ struct bpf_link_create_opts { __u32 iter_info_len; __u32 target_btf_id; union { + struct { + __u64 bpf_cookie; + } tracing; struct { __u64 bpf_cookie; } perf_event; diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 43161fdd44bb..ab8cfb59073a 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -10611,6 +10611,39 @@ struct bpf_link *bpf_program__attach_trace(const struct bpf_program *prog) return bpf_program__attach_btf_id(prog); } +struct bpf_link *bpf_program__attach_trace_opts(const struct bpf_program *prog, + const struct bpf_trace_opts *opts) +{ + char errmsg[STRERR_BUFSIZE]; + struct bpf_link *link; + int prog_fd, pfd; + + LIBBPF_OPTS(bpf_link_create_opts, link_opts); + + prog_fd = bpf_program__fd(prog); + if (prog_fd < 0) { + pr_warn("prog '%s': can't attach before loaded\n", prog->name); + return libbpf_err_ptr(-EINVAL); + } + + link = calloc(1, sizeof(*link)); + if (!link) + return libbpf_err_ptr(-ENOMEM); + link->detach = &bpf_link__detach_fd; + + link_opts.tracing.bpf_cookie = OPTS_GET(opts, bpf_cookie, 0); + pfd = bpf_link_create(prog_fd, 0, prog->expected_attach_type, &link_opts); + if (pfd < 0) { + pfd = -errno; + free(link); + pr_warn("prog '%s': failed to attach: %s\n", + prog->name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); + return libbpf_err_ptr(pfd); + } + link->fd = pfd; + return (struct bpf_link *)link; +} + struct bpf_link *bpf_program__attach_lsm(const struct bpf_program *prog) { return bpf_program__attach_btf_id(prog); diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index c1b0c2ef14d8..42aff476bcb0 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -501,8 +501,20 @@ bpf_program__attach_tracepoint_opts(const struct bpf_program *prog, LIBBPF_API struct bpf_link * bpf_program__attach_raw_tracepoint(const struct bpf_program *prog, const char *tp_name); + +struct bpf_trace_opts { + /* size of this struct, for forward/backward compatibility */ + size_t sz; + /* custom user-provided value fetchable through bpf_get_attach_cookie() */ + __u64 bpf_cookie; +}; +#define bpf_trace_opts__last_field bpf_cookie + LIBBPF_API struct bpf_link * bpf_program__attach_trace(const struct bpf_program *prog); +LIBBPF_API struct bpf_link * +bpf_program__attach_trace_opts(const struct bpf_program *prog, const struct bpf_trace_opts *opts); + LIBBPF_API struct bpf_link * bpf_program__attach_lsm(const struct bpf_program *prog); LIBBPF_API struct bpf_link * diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index df1b947792c8..e2f592b2f6a9 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -424,6 +424,7 @@ LIBBPF_0.6.0 { LIBBPF_0.7.0 { global: bpf_btf_load; + bpf_program__attach_trace_opts; bpf_program__expected_attach_type; bpf_program__log_buf; bpf_program__log_level; From patchwork Thu Apr 7 19:25:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kui-Feng Lee X-Patchwork-Id: 12805643 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F145C433F5 for ; Thu, 7 Apr 2022 19:26:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231137AbiDGT2t (ORCPT ); Thu, 7 Apr 2022 15:28:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47602 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230523AbiDGT2s (ORCPT ); Thu, 7 Apr 2022 15:28:48 -0400 Received: from mx0a-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6CE98286A6C for ; Thu, 7 Apr 2022 12:26:38 -0700 (PDT) Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.16.1.2/8.16.1.2) with ESMTP id 237IBDBk024615 for ; Thu, 7 Apr 2022 12:26:37 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=2npb6w9pLqHe8jLCqjFBryFIEuhlwR1ZQ+gPXKdT4jE=; b=cEwDMAWBCIgReoFLYXNCjctxUlZG3aA1PwTcZCSugjFBxxGnfr2s4gmTGr8tQrwEKfvH C2IfH0tcRSlFSjfViFSF48AA0adYovmqyFRosz9NLj1qjFgWms7Jg+ExBCianTYaaPBZ 88+SRwTgniLr1YPeGRFuYV/ewl/OmCqAGlw= Received: from mail.thefacebook.com ([163.114.132.120]) by m0001303.ppops.net (PPS) with ESMTPS id 3f9bb3kvxh-4 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 07 Apr 2022 12:26:37 -0700 Received: from twshared39027.37.frc1.facebook.com (2620:10d:c085:108::4) by mail.thefacebook.com (2620:10d:c085:21d::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Thu, 7 Apr 2022 12:26:35 -0700 Received: by devbig931.frc1.facebook.com (Postfix, from userid 460691) id 9ED38200EE91; Thu, 7 Apr 2022 12:26:27 -0700 (PDT) From: Kui-Feng Lee To: , , , , CC: Kui-Feng Lee Subject: [PATCH bpf-next v3 5/5] selftest/bpf: The test cses of BPF cookie for fentry/fexit/fmod_ret. Date: Thu, 7 Apr 2022 12:25:52 -0700 Message-ID: <20220407192552.2343076-6-kuifeng@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220407192552.2343076-1-kuifeng@fb.com> References: <20220407192552.2343076-1-kuifeng@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-ORIG-GUID: Gwkqn6qIfbDrf3Fu_iW4xF2IW7uq1VYm X-Proofpoint-GUID: Gwkqn6qIfbDrf3Fu_iW4xF2IW7uq1VYm X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.425,FMLib:17.11.64.514 definitions=2022-04-07_04,2022-04-07_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Make sure BPF cookies are correct for fentry/fexit/fmod_ret. Signed-off-by: Kui-Feng Lee --- .../selftests/bpf/prog_tests/bpf_cookie.c | 52 +++++++++++++++++++ .../selftests/bpf/progs/test_bpf_cookie.c | 24 +++++++++ 2 files changed, 76 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c index 0612e79a9281..16385f0c4031 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c @@ -237,6 +237,56 @@ static void pe_subtest(struct test_bpf_cookie *skel) bpf_link__destroy(link); } +static void tracing_subtest(struct test_bpf_cookie *skel) +{ + __u64 cookie; + int prog_fd; + int fentry_fd = -1, fexit_fd = -1, fmod_ret_fd = -1; + + LIBBPF_OPTS(bpf_test_run_opts, opts, .repeat = 1); + LIBBPF_OPTS(bpf_link_create_opts, link_opts); + + skel->bss->fentry_res = 0; + skel->bss->fexit_res = 0; + + cookie = 0x100000; + prog_fd = bpf_program__fd(skel->progs.fentry_test1); + link_opts.tracing.bpf_cookie = cookie; + fentry_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FENTRY, &link_opts); + + cookie = 0x200000; + prog_fd = bpf_program__fd(skel->progs.fexit_test1); + link_opts.tracing.bpf_cookie = cookie; + fexit_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FEXIT, &link_opts); + if (!ASSERT_GE(fexit_fd, 0, "fexit.open")) + goto cleanup; + + cookie = 0x300000; + prog_fd = bpf_program__fd(skel->progs.fmod_ret_test); + link_opts.tracing.bpf_cookie = cookie; + fmod_ret_fd = bpf_link_create(prog_fd, 0, BPF_MODIFY_RETURN, &link_opts); + if (!ASSERT_GE(fmod_ret_fd, 0, "fmod_ret.opoen")) + goto cleanup; + + prog_fd = bpf_program__fd(skel->progs.fentry_test1); + bpf_prog_test_run_opts(prog_fd, &opts); + + prog_fd = bpf_program__fd(skel->progs.fmod_ret_test); + bpf_prog_test_run_opts(prog_fd, &opts); + + ASSERT_EQ(skel->bss->fentry_res, 0x100000, "fentry_res"); + ASSERT_EQ(skel->bss->fexit_res, 0x200000, "fexit_res"); + ASSERT_EQ(skel->bss->fmod_ret_res, 0x300000, "fmod_ret_res"); + +cleanup: + if (fentry_fd >= 0) + close(fentry_fd); + if (fexit_fd >= 0) + close(fexit_fd); + if (fmod_ret_fd >= 0) + close(fmod_ret_fd); +} + void test_bpf_cookie(void) { struct test_bpf_cookie *skel; @@ -255,6 +305,8 @@ void test_bpf_cookie(void) tp_subtest(skel); if (test__start_subtest("perf_event")) pe_subtest(skel); + if (test__start_subtest("trampoline")) + tracing_subtest(skel); test_bpf_cookie__destroy(skel); } diff --git a/tools/testing/selftests/bpf/progs/test_bpf_cookie.c b/tools/testing/selftests/bpf/progs/test_bpf_cookie.c index 2d3a7710e2ce..a9f83f46e7b7 100644 --- a/tools/testing/selftests/bpf/progs/test_bpf_cookie.c +++ b/tools/testing/selftests/bpf/progs/test_bpf_cookie.c @@ -14,6 +14,9 @@ int uprobe_res; int uretprobe_res; int tp_res; int pe_res; +int fentry_res; +int fexit_res; +int fmod_ret_res; static void update(void *ctx, int *res) { @@ -82,4 +85,25 @@ int handle_pe(struct pt_regs *ctx) return 0; } +SEC("fentry/bpf_fentry_test1") +int BPF_PROG(fentry_test1, int a) +{ + update(ctx, &fentry_res); + return 0; +} + +SEC("fexit/bpf_fentry_test1") +int BPF_PROG(fexit_test1, int a, int ret) +{ + update(ctx, &fexit_res); + return 0; +} + +SEC("fmod_ret/bpf_modify_return_test") +int BPF_PROG(fmod_ret_test, int _a, int *_b, int _ret) +{ + update(ctx, &fmod_ret_res); + return 1234; +} + char _license[] SEC("license") = "GPL";