From mboxrd@z Thu Jan 1 00:00:00 1970 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 5EB34C433FE for ; Wed, 18 May 2022 22:58:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230470AbiERW6D (ORCPT ); Wed, 18 May 2022 18:58:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40850 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231351AbiERW4J (ORCPT ); Wed, 18 May 2022 18:56:09 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4775F2265E9 for ; Wed, 18 May 2022 15:55:36 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id 135-20020a25058d000000b0064dd6bc9cfdso2874197ybf.23 for ; Wed, 18 May 2022 15:55:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=TmU3TPEQ71AzbFMJrCVCfzfvu+DBevj7Y5+l60jkcnw=; b=Hsr7rkeJB/HX80tKJuoXVSAlGsYmIOfqMCoRsDOMv1A2V5RuaCNNR9BVnegOWYkxmt 0Ldw4GgDSFFP94Eo6iEu4ccs2lD9/bQO01WdNGDrOql71DggkXNccGW+veZxtdVmbmNd 4GyY/NwyeH2qsfAxqsNQ7a5e6gpTko9qlSpuN6dx+GI5U8m/Atdb6PrAX5xlPSImfI4c O0drbzz0IQ60i3gbPsQlYfTWRDqfm/dYA/3ec8lnINkRU6Q4I3MK2gL4TMPD90RKQVbM BHX3Sm+ZGZfiMagU5vi7LOeSCeI2nrJtyb72oX2bgj+VOYbKif1O9FQEb10LP1lDb73e jTjg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=TmU3TPEQ71AzbFMJrCVCfzfvu+DBevj7Y5+l60jkcnw=; b=jWiH+MDqty72pghDZPvvWuu07oiFDC0n0Qfk5weRhfPr6OCJ3ixBTPcJqQOmYALHvf eEAn1qHU5+hEGrVCiiGhxXKIVICH778m9aAFoISVZtmPIyf5SsabJ+5WTL9c+j+VNrGl I0xqTagS3JyRtoOh8FLTymL0lrq0N/0Vk9rVhuRAVi+Ag2FN6PmNQUEXFENTRGNvkaXs 7t7NHJQz6vsF8dkyy4CtmnHuvAVOyD3KNjDA8c0ER6TJA5t4DiB8KrtrcJ5NGutrA1Nz YVYfsa4K+r9gL0vklE/xpLbyHOX/yi00O3RfiTsu7IMmJebLzV0YV4KiHON6YdO2Xkiq GHMw== X-Gm-Message-State: AOAM531bMvvIfLDKOsEotWcIGa1PT0SztYBNW2s3jxvsnJQC7L8lDpxw kNyzbq1uCI6UAwOIA6kaDi5APrhT1T8TEHuUPL4LtfhfZBcQut/wZ46b+22x2J5ZQhLn6Krwum3 LUj8xWdId0XpF7DJ1OMVv+iZ4TV+9SWyAZ6WwXEV00ri/l/MAu+Wm/w== X-Google-Smtp-Source: ABdhPJxvP2lVCm3fAuqiwDxhA5l3tJKZjDngrv6uB7L6UsvWUmjra1avVr2Wlppvi3ARakPcoVEBpik= X-Received: from sdf2.svl.corp.google.com ([2620:15c:2c4:201:f763:3448:2567:bf00]) (user=sdf job=sendgmr) by 2002:a25:dc02:0:b0:64d:b6a3:e0bf with SMTP id y2-20020a25dc02000000b0064db6a3e0bfmr1810299ybe.41.1652914535428; Wed, 18 May 2022 15:55:35 -0700 (PDT) Date: Wed, 18 May 2022 15:55:21 -0700 In-Reply-To: <20220518225531.558008-1-sdf@google.com> Message-Id: <20220518225531.558008-2-sdf@google.com> Mime-Version: 1.0 References: <20220518225531.558008-1-sdf@google.com> X-Mailer: git-send-email 2.36.1.124.g0e6072fb45-goog Subject: [PATCH bpf-next v7 01/11] bpf: add bpf_func_t and trampoline helpers From: Stanislav Fomichev To: netdev@vger.kernel.org, bpf@vger.kernel.org Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, Stanislav Fomichev Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org I'll be adding lsm cgroup specific helpers that grab trampoline mutex. No functional changes. Signed-off-by: Stanislav Fomichev --- include/linux/bpf.h | 11 ++++---- kernel/bpf/trampoline.c | 62 ++++++++++++++++++++++------------------- 2 files changed, 38 insertions(+), 35 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index c107392b0ba7..ea3674a415f9 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -53,6 +53,8 @@ typedef u64 (*bpf_callback_t)(u64, u64, u64, u64, u64); typedef int (*bpf_iter_init_seq_priv_t)(void *private_data, struct bpf_iter_aux_info *aux); typedef void (*bpf_iter_fini_seq_priv_t)(void *private_data); +typedef unsigned int (*bpf_func_t)(const void *, + const struct bpf_insn *); struct bpf_iter_seq_info { const struct seq_operations *seq_ops; bpf_iter_init_seq_priv_t init_seq_private; @@ -853,8 +855,7 @@ struct bpf_dispatcher { static __always_inline __nocfi unsigned int bpf_dispatcher_nop_func( const void *ctx, const struct bpf_insn *insnsi, - unsigned int (*bpf_func)(const void *, - const struct bpf_insn *)) + bpf_func_t bpf_func) { return bpf_func(ctx, insnsi); } @@ -883,8 +884,7 @@ int arch_prepare_bpf_dispatcher(void *image, s64 *funcs, int num_funcs); noinline __nocfi unsigned int bpf_dispatcher_##name##_func( \ const void *ctx, \ const struct bpf_insn *insnsi, \ - unsigned int (*bpf_func)(const void *, \ - const struct bpf_insn *)) \ + bpf_func_t bpf_func) \ { \ return bpf_func(ctx, insnsi); \ } \ @@ -895,8 +895,7 @@ int arch_prepare_bpf_dispatcher(void *image, s64 *funcs, int num_funcs); unsigned int bpf_dispatcher_##name##_func( \ const void *ctx, \ const struct bpf_insn *insnsi, \ - unsigned int (*bpf_func)(const void *, \ - const struct bpf_insn *)); \ + bpf_func_t bpf_func); \ extern struct bpf_dispatcher bpf_dispatcher_##name; #define BPF_DISPATCHER_FUNC(name) bpf_dispatcher_##name##_func #define BPF_DISPATCHER_PTR(name) (&bpf_dispatcher_##name) diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index 93c7675f0c9e..01ce78c1df80 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -410,7 +410,7 @@ static enum bpf_tramp_prog_type bpf_attach_type_to_tramp(struct bpf_prog *prog) } } -int bpf_trampoline_link_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr) +static 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; @@ -418,44 +418,33 @@ int bpf_trampoline_link_prog(struct bpf_tramp_link *link, struct bpf_trampoline int cnt = 0, i; kind = bpf_attach_type_to_tramp(link->link.prog); - mutex_lock(&tr->mutex); - if (tr->extension_prog) { + if (tr->extension_prog) /* cannot attach fentry/fexit if extension prog is attached. * cannot overwrite extension prog either. */ - err = -EBUSY; - goto out; - } + return -EBUSY; for (i = 0; i < BPF_TRAMP_MAX; i++) cnt += tr->progs_cnt[i]; if (kind == BPF_TRAMP_REPLACE) { /* Cannot attach extension if fentry/fexit are in use. */ - if (cnt) { - err = -EBUSY; - goto out; - } + if (cnt) + return -EBUSY; tr->extension_prog = link->link.prog; - err = bpf_arch_text_poke(tr->func.addr, BPF_MOD_JUMP, NULL, - link->link.prog->bpf_func); - goto out; - } - if (cnt >= BPF_MAX_TRAMP_LINKS) { - err = -E2BIG; - goto out; + return bpf_arch_text_poke(tr->func.addr, BPF_MOD_JUMP, NULL, + link->link.prog->bpf_func); } - if (!hlist_unhashed(&link->tramp_hlist)) { + if (cnt >= BPF_MAX_TRAMP_LINKS) + return -E2BIG; + if (!hlist_unhashed(&link->tramp_hlist)) /* prog already linked */ - err = -EBUSY; - goto out; - } + return -EBUSY; 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; + return -EBUSY; } hlist_add_head(&link->tramp_hlist, &tr->progs_hlist[kind]); @@ -465,30 +454,45 @@ int bpf_trampoline_link_prog(struct bpf_tramp_link *link, struct bpf_trampoline hlist_del_init(&link->tramp_hlist); tr->progs_cnt[kind]--; } -out: + return err; +} + +int bpf_trampoline_link_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr) +{ + int err; + + mutex_lock(&tr->mutex); + err = __bpf_trampoline_link_prog(link, tr); mutex_unlock(&tr->mutex); return err; } /* bpf_trampoline_unlink_prog() should never fail. */ -int bpf_trampoline_unlink_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr) +static 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(link->link.prog); - mutex_lock(&tr->mutex); if (kind == BPF_TRAMP_REPLACE) { WARN_ON_ONCE(!tr->extension_prog); err = bpf_arch_text_poke(tr->func.addr, BPF_MOD_JUMP, tr->extension_prog->bpf_func, NULL); tr->extension_prog = NULL; - goto out; + return err; } hlist_del_init(&link->tramp_hlist); tr->progs_cnt[kind]--; - err = bpf_trampoline_update(tr); -out: + return bpf_trampoline_update(tr); +} + +/* bpf_trampoline_unlink_prog() should never fail. */ +int bpf_trampoline_unlink_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr) +{ + int err; + + mutex_lock(&tr->mutex); + err = __bpf_trampoline_unlink_prog(link, tr); mutex_unlock(&tr->mutex); return err; } -- 2.36.1.124.g0e6072fb45-goog