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 8F4DDCCA483 for ; Wed, 22 Jun 2022 16:03:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376316AbiFVQDy (ORCPT ); Wed, 22 Jun 2022 12:03:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38908 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359804AbiFVQDv (ORCPT ); Wed, 22 Jun 2022 12:03:51 -0400 Received: from mail-pf1-x44a.google.com (mail-pf1-x44a.google.com [IPv6:2607:f8b0:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A19D723BC9 for ; Wed, 22 Jun 2022 09:03:50 -0700 (PDT) Received: by mail-pf1-x44a.google.com with SMTP id b18-20020aa78ed2000000b0052541d34055so1554921pfr.23 for ; Wed, 22 Jun 2022 09:03:50 -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=BZLj2BtPGrZgZkseCvj4VIieJkyvO0jKrbp8waQGAro=; b=IgqM8qptxGGw4VoIRrGIfWB5THA67tOOG/oqeacoNlTtNsNy34JGDkEuVpvT07hrXU ZBxrFqz+8YiNThMch/kMBbEdX5BMoloStsrjQPYKcBLsPVTQcbxEeYhuQ6XsWn4gSe95 koxgmWN9ZY5cZs+C87oF0y0o8GblccCCl+cfEpXOdEniCpyH8BTXgqkbpnkYyEvxcp1e njDol1obEfn+fmsD9cx2FY5bAaNMuuwvCog76BS1XbRKpyuq0Y2+Xk7VNbMCIiTFgsVV 1zJADi8suUBFHja4ifQyrJjfScba9kY8vQ/TffeimBTYmD77ucjf7u7dRf1KAmEZZvAT 5FBg== 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=BZLj2BtPGrZgZkseCvj4VIieJkyvO0jKrbp8waQGAro=; b=Nxts7m7mDTIe1jYUF/uuPYOPt4A12fpW0gdYxBeLwq0GvPPCopSuCGwa7KXX6liive 8yNsJK2R+j+5LLtLSU+m+CnUjqhOWl8F26eImbKVfKcGR3q2367kDKUFGbBeXQkdkC7r 8Z0IcN8omhpU5A5c/sm3SusrqjLNG++qPXBV5Wmsst1sPPoKo39SmrgeqNzA6aYkyLIP 8+x8IOZ30wkl37nzN+tOI/DEUH9ec9AF+DN+gmZAMk93t7R3EymOvjcKNNF9v0GCv1LJ 8A8+y5kZD/ZgpLG37hqMrNWBurSL7rQ5mYSyUorfNG48tpNF53ZwnNoK43BtCEA3zG2f BcxQ== X-Gm-Message-State: AJIora98t7/okToSnH4444rZbrVrS/17TKty+Rl/WUslaLbW0N4FViue FpQao6SMRnRwPH9hl5KiAlhhQjZaCKTw5gopDn/KvKpL9w7qxukAcA2RccmAuIUXAutzSb5UoC2 /Yj36oXX69dJrFC2ydF2SryW5jOKpAKkHg2Eyu6C31SrUFSzLeNJcxw== X-Google-Smtp-Source: AGRyM1tv+570oLHWjWons6lvJ8/+w6/IQtGRChXcOOLDt70247mBOP5H7JFt85dhxdihbL5Dr5gfDvs= X-Received: from sdf.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5935]) (user=sdf job=sendgmr) by 2002:a05:6a00:844:b0:525:1785:e26f with SMTP id q4-20020a056a00084400b005251785e26fmr21306666pfk.86.1655913829870; Wed, 22 Jun 2022 09:03:49 -0700 (PDT) Date: Wed, 22 Jun 2022 09:03:36 -0700 In-Reply-To: <20220622160346.967594-1-sdf@google.com> Message-Id: <20220622160346.967594-2-sdf@google.com> Mime-Version: 1.0 References: <20220622160346.967594-1-sdf@google.com> X-Mailer: git-send-email 2.37.0.rc0.104.g0611611a94-goog Subject: [PATCH bpf-next v10 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 , Martin KaFai Lau 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. Reviewed-by: Martin KaFai Lau Signed-off-by: Stanislav Fomichev --- include/linux/bpf.h | 11 ++++--- kernel/bpf/trampoline.c | 63 +++++++++++++++++++++-------------------- 2 files changed, 38 insertions(+), 36 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index d05e1495a06e..d547be9db75f 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -56,6 +56,8 @@ 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; @@ -879,8 +881,7 @@ 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); } @@ -909,8 +910,7 @@ 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); \ } \ @@ -921,8 +921,7 @@ 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..5466e15be61f 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 +454,44 @@ 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; } -- 2.37.0.rc0.104.g0611611a94-goog