From patchwork Tue Nov 15 21:19:01 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13044181 X-Patchwork-Delegate: kuba@kernel.org 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 8D9D6C4332F for ; Tue, 15 Nov 2022 21:20:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232142AbiKOVT5 (ORCPT ); Tue, 15 Nov 2022 16:19:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231230AbiKOVTu (ORCPT ); Tue, 15 Nov 2022 16:19:50 -0500 Received: from mail-wr1-x432.google.com (mail-wr1-x432.google.com [IPv6:2a00:1450:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1836621E27 for ; Tue, 15 Nov 2022 13:19:46 -0800 (PST) Received: by mail-wr1-x432.google.com with SMTP id g12so26360084wrs.10 for ; Tue, 15 Nov 2022 13:19:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=G6ZrelBNbx4bHqPFCl+9tJGrR84oe90P9c4JQMnU//c=; b=JEiTnfyG7jVn1GJy603cURHFeY1WtTxd95lLwGzpaA8HBNnXKesxowihb3ga39IPKr dS5gw1ezZx4dCaWPIAoHblLuwwFa6ESLDtWGU0E0Ok22CK32mdOJtxTg78+U4HkxGv8q y5Pn2DaPOFVFX/NDzqa+wg9sbjgYg1BDrSBkL0RGFRFGcUGOelgL132hPXG0Fny9hhGI tvgtu1d6G2g0fgsL/ThFkBdPrNOzJ9XQIJMtO1gIZ7b15+v0bRb5bQ4shpCXKN6bEmJz TbF8pwAK2SxsONFHVj/j2l1iXpbz8BLy2ORo0gkpaTyy0WLlzkiOOj6/nbupYYZderOi lCTA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=G6ZrelBNbx4bHqPFCl+9tJGrR84oe90P9c4JQMnU//c=; b=SOR8/Uza78ll68PhMumfh1lHybRbYSuGa8pEsjiG2NbD3sjm713mn9Frd4PpoDs0eP +7vB/hG9j6untv2G01yeQw1QGOv2a7zBi+5V+zzulQXb7ys0k+YNacHOgx1z2Z1FlgO2 oKO9kJhrTN/g0fzctHS+Y1MUazqWGlf+5Nv1Pfvob8fGV2NkxuIAOc+PCWXAyJIj/75i 1IfVlAwoDaUsTPVwLO7exqfMMlaclK/zzKYzrXloNcTsiGGo27PaGruu2rABsnL8y5fX Id1UMCZqq8GD4CJ2CiBmqMnw6F/FJSC7NOPj6jqKRC6K9xb88Q98wJvcKUy0SoudWeSp NVvA== X-Gm-Message-State: ANoB5pnb0MXEkTl0hkYBbafh6kIOWcM3LRRiM0jTjxOtD6ZwbX12pV9j 9ii+FbyRgdT1aBIkoiLUvIz+cg== X-Google-Smtp-Source: AA0mqf6ot1+pW00qvrkf/vvbjKqUy0/Nsglu2a7sKnGP3DS2KJSGUcA4Re4Z5gF68zjEj6eMwE5YFA== X-Received: by 2002:a05:6000:61a:b0:241:6e0a:bfe6 with SMTP id bn26-20020a056000061a00b002416e0abfe6mr12006959wrb.34.1668547154291; Tue, 15 Nov 2022 13:19:14 -0800 (PST) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id n41-20020a05600c502900b003c65c9a36dfsm17201487wmr.48.2022.11.15.13.19.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Nov 2022 13:19:13 -0800 (PST) From: Dmitry Safonov To: linux-kernel@vger.kernel.org, David Ahern , Eric Dumazet , Peter Zijlstra Cc: Dmitry Safonov , Ard Biesheuvel , Bob Gilligan , "David S. Miller" , Dmitry Safonov <0x7f454c46@gmail.com>, Francesco Ruggeri , Hideaki YOSHIFUJI , Jakub Kicinski , Jason Baron , Josh Poimboeuf , Paolo Abeni , Salam Noureddine , Steven Rostedt , netdev@vger.kernel.org Subject: [PATCH v4 1/5] jump_label: Prevent key->enabled int overflow Date: Tue, 15 Nov 2022 21:19:01 +0000 Message-Id: <20221115211905.1685426-2-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221115211905.1685426-1-dima@arista.com> References: <20221115211905.1685426-1-dima@arista.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 1. With CONFIG_JUMP_LABEL=n static_key_slow_inc() doesn't have any protection against key->enabled refcounter overflow. 2. With CONFIG_JUMP_LABEL=y static_key_slow_inc_cpuslocked() still may turn the refcounter negative as (v + 1) may overflow. key->enabled is indeed a ref-counter as it's documented in multiple places: top comment in jump_label.h, Documentation/staging/static-keys.rst, etc. As -1 is reserved for static key that's in process of being enabled, functions would break with negative key->enabled refcount: - for CONFIG_JUMP_LABEL=n negative return of static_key_count() breaks static_key_false(), static_key_true() - the ref counter may become 0 from negative side by too many static_key_slow_inc() calls and lead to use-after-free issues. These flaws result in that some users have to introduce an additional mutex and prevent the reference counter from overflowing themselves, see bpf_enable_runtime_stats() checking the counter against INT_MAX / 2. Prevent the reference counter overflow by checking if (v + 1) > 0. Change functions API to return whether the increment was successful. Signed-off-by: Dmitry Safonov --- include/linux/jump_label.h | 19 +++++++++++--- kernel/jump_label.c | 54 +++++++++++++++++++++++++++++--------- 2 files changed, 57 insertions(+), 16 deletions(-) diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index 570831ca9951..c0a02d4c2ea2 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -224,9 +224,9 @@ extern bool arch_jump_label_transform_queue(struct jump_entry *entry, enum jump_label_type type); extern void arch_jump_label_transform_apply(void); extern int jump_label_text_reserved(void *start, void *end); -extern void static_key_slow_inc(struct static_key *key); +extern bool static_key_slow_inc(struct static_key *key); extern void static_key_slow_dec(struct static_key *key); -extern void static_key_slow_inc_cpuslocked(struct static_key *key); +extern bool static_key_slow_inc_cpuslocked(struct static_key *key); extern void static_key_slow_dec_cpuslocked(struct static_key *key); extern int static_key_count(struct static_key *key); extern void static_key_enable(struct static_key *key); @@ -278,10 +278,21 @@ static __always_inline bool static_key_true(struct static_key *key) return false; } -static inline void static_key_slow_inc(struct static_key *key) +static inline bool static_key_slow_inc(struct static_key *key) { + int v; + STATIC_KEY_CHECK_USE(key); - atomic_inc(&key->enabled); + /* + * Prevent key->enabled getting negative to follow the same semantics + * as for CONFIG_JUMP_LABEL=y, see kernel/jump_label.c comment. + */ + v = atomic_read(&key->enabled); + do { + if (v < 0 || (v + 1) < 0) + return false; + } while (!likely(atomic_try_cmpxchg(&key->enabled, &v, v + 1))); + return true; } static inline void static_key_slow_dec(struct static_key *key) diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 4d6c6f5f60db..677a6674c130 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -113,9 +113,38 @@ int static_key_count(struct static_key *key) } EXPORT_SYMBOL_GPL(static_key_count); -void static_key_slow_inc_cpuslocked(struct static_key *key) +/*** + * static_key_fast_inc_not_negative - adds a user for a static key + * @key: static key that must be already enabled + * + * The caller must make sure that the static key can't get disabled while + * in this function. It doesn't patch jump labels, only adds a user to + * an already enabled static key. + * + * Returns true if the increment was done. + */ +static bool static_key_fast_inc_not_negative(struct static_key *key) { + int v; + STATIC_KEY_CHECK_USE(key); + /* + * Negative key->enabled has a special meaning: it sends + * static_key_slow_inc() down the slow path, and it is non-zero + * so it counts as "enabled" in jump_label_update(). Note that + * atomic_inc_unless_negative() checks >= 0, so roll our own. + */ + v = atomic_read(&key->enabled); + do { + if (v <= 0 || (v + 1) < 0) + return false; + } while (!likely(atomic_try_cmpxchg(&key->enabled, &v, v + 1))); + + return true; +} + +bool static_key_slow_inc_cpuslocked(struct static_key *key) +{ lockdep_assert_cpus_held(); /* @@ -124,15 +153,9 @@ void static_key_slow_inc_cpuslocked(struct static_key *key) * jump_label_update() process. At the same time, however, * the jump_label_update() call below wants to see * static_key_enabled(&key) for jumps to be updated properly. - * - * So give a special meaning to negative key->enabled: it sends - * static_key_slow_inc() down the slow path, and it is non-zero - * so it counts as "enabled" in jump_label_update(). Note that - * atomic_inc_unless_negative() checks >= 0, so roll our own. */ - for (int v = atomic_read(&key->enabled); v > 0; ) - if (likely(atomic_try_cmpxchg(&key->enabled, &v, v + 1))) - return; + if (static_key_fast_inc_not_negative(key)) + return true; jump_label_lock(); if (atomic_read(&key->enabled) == 0) { @@ -144,16 +167,23 @@ void static_key_slow_inc_cpuslocked(struct static_key *key) */ atomic_set_release(&key->enabled, 1); } else { - atomic_inc(&key->enabled); + if (WARN_ON_ONCE(!static_key_fast_inc_not_negative(key))) { + jump_label_unlock(); + return false; + } } jump_label_unlock(); + return true; } -void static_key_slow_inc(struct static_key *key) +bool static_key_slow_inc(struct static_key *key) { + bool ret; + cpus_read_lock(); - static_key_slow_inc_cpuslocked(key); + ret = static_key_slow_inc_cpuslocked(key); cpus_read_unlock(); + return ret; } EXPORT_SYMBOL_GPL(static_key_slow_inc); From patchwork Tue Nov 15 21:19:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13044183 X-Patchwork-Delegate: kuba@kernel.org 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 CDAB7C433FE for ; Tue, 15 Nov 2022 21:20:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238654AbiKOVUD (ORCPT ); Tue, 15 Nov 2022 16:20:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45302 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231815AbiKOVTv (ORCPT ); Tue, 15 Nov 2022 16:19:51 -0500 Received: from mail-wr1-x433.google.com (mail-wr1-x433.google.com [IPv6:2a00:1450:4864:20::433]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2904222BE1 for ; Tue, 15 Nov 2022 13:19:46 -0800 (PST) Received: by mail-wr1-x433.google.com with SMTP id a14so26564151wru.5 for ; Tue, 15 Nov 2022 13:19:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=CbvR8VuafE8eZOle2gcxzJnLTEWWuPtnJ8HojgPG8FI=; b=So8k6c4YUMYle8Ql/rzA3xQ5ONAF2vFeIa6jwrybulTP13y/R3ALP9iTxURI6rMu6K ZIyS+KTc8uBbD4SJ/rVRGyi71ryjisJwpfc9gslhHK5FvC5NCBr0UJswTDAWAsMnc9fh tCuecNekzJkN3dZuHBa+Ce2pqo+Y8bRl4d26M/C4I/NrGZxRnqGdLdzEBK4Cp2sdfl23 MFyDAZaCvFLAhK1o953S6zagd00CG4fVMo/lLTsXr1FufWFd4J5fgw7uzphBOHvb2+OO NdLg7MRgSYitg/HwlWdd0Y76wIdRrO95Laa30A+hut7EAcrJQMTqL6hJ1rgHzMNyjsam 5YLw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=CbvR8VuafE8eZOle2gcxzJnLTEWWuPtnJ8HojgPG8FI=; b=M4z/9B7XbZDCgn3VyfD5lnk1iy1zowTtB/K1vDGnYuF/5QJ2nviz4Ht2xNQBjoe+LV Xon/ObsMvIGMu7Mrjrr+ijZuL8cz9n9FggI9XNdRCh6pe31nICogpc5MbOo+baiVQP0A OwE0rMS+dL1je1DstNhwL5vKPezwQbOkganZTianzTNhIHoDjrPOQSlAfogSoH6wsu2Z KYAyvu5GZatiwGvYcNUiOmClhOyihg90mvoVz70tJFCYUiBSouPrwPadCACw+rl/V2mI M35Q0ohx5AaMGMRNgOaaDuT1R9+Rf6h/pG3XJUSv5bxhLDjvWHZSsjsGEKg83+5I3mUg ewMQ== X-Gm-Message-State: ANoB5pkZY15b3jMO4/nxfKP59TzS/n8flOfQn/Oj/rQXUDAAQHqH8vbl hT+JcHuVQ6RcyXgkXTd6jKvE/Q== X-Google-Smtp-Source: AA0mqf4C0ZYwK4qMyUW2YR0vkq76wmJKPm94WV0z55/QLyGfvJuFncg2LYImZwYKD80rqFdMIIPTBw== X-Received: by 2002:a5d:4d49:0:b0:235:470e:a9f3 with SMTP id a9-20020a5d4d49000000b00235470ea9f3mr11679576wru.263.1668547155798; Tue, 15 Nov 2022 13:19:15 -0800 (PST) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id n41-20020a05600c502900b003c65c9a36dfsm17201487wmr.48.2022.11.15.13.19.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Nov 2022 13:19:15 -0800 (PST) From: Dmitry Safonov To: linux-kernel@vger.kernel.org, David Ahern , Eric Dumazet , Peter Zijlstra Cc: Dmitry Safonov , Ard Biesheuvel , Bob Gilligan , "David S. Miller" , Dmitry Safonov <0x7f454c46@gmail.com>, Francesco Ruggeri , Hideaki YOSHIFUJI , Jakub Kicinski , Jason Baron , Josh Poimboeuf , Paolo Abeni , Salam Noureddine , Steven Rostedt , netdev@vger.kernel.org Subject: [PATCH v4 2/5] net/tcp: Separate tcp_md5sig_info allocation into tcp_md5sig_info_add() Date: Tue, 15 Nov 2022 21:19:02 +0000 Message-Id: <20221115211905.1685426-3-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221115211905.1685426-1-dima@arista.com> References: <20221115211905.1685426-1-dima@arista.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Add a helper to allocate tcp_md5sig_info, that will help later to do/allocate things when info allocated, once per socket. Signed-off-by: Dmitry Safonov Reviewed-by: Eric Dumazet --- net/ipv4/tcp_ipv4.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 87d440f47a70..fae80b1a1796 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1172,6 +1172,24 @@ struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk, } EXPORT_SYMBOL(tcp_v4_md5_lookup); +static int tcp_md5sig_info_add(struct sock *sk, gfp_t gfp) +{ + struct tcp_sock *tp = tcp_sk(sk); + struct tcp_md5sig_info *md5sig; + + if (rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk))) + return 0; + + md5sig = kmalloc(sizeof(*md5sig), gfp); + if (!md5sig) + return -ENOMEM; + + sk_gso_disable(sk); + INIT_HLIST_HEAD(&md5sig->head); + rcu_assign_pointer(tp->md5sig_info, md5sig); + return 0; +} + /* This can be called on a newly created socket, from other files */ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags, @@ -1202,17 +1220,11 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, return 0; } + if (tcp_md5sig_info_add(sk, gfp)) + return -ENOMEM; + md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk)); - if (!md5sig) { - md5sig = kmalloc(sizeof(*md5sig), gfp); - if (!md5sig) - return -ENOMEM; - - sk_gso_disable(sk); - INIT_HLIST_HEAD(&md5sig->head); - rcu_assign_pointer(tp->md5sig_info, md5sig); - } key = sock_kmalloc(sk, sizeof(*key), gfp | __GFP_ZERO); if (!key) From patchwork Tue Nov 15 21:19:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13044184 X-Patchwork-Delegate: kuba@kernel.org 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 11558C433FE for ; Tue, 15 Nov 2022 21:20:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231263AbiKOVUG (ORCPT ); Tue, 15 Nov 2022 16:20:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45250 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229642AbiKOVTy (ORCPT ); Tue, 15 Nov 2022 16:19:54 -0500 Received: from mail-wr1-x432.google.com (mail-wr1-x432.google.com [IPv6:2a00:1450:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3166622BE9 for ; Tue, 15 Nov 2022 13:19:46 -0800 (PST) Received: by mail-wr1-x432.google.com with SMTP id y16so26538805wrt.12 for ; Tue, 15 Nov 2022 13:19:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=8ytIn/f+EUf0Gut52ap1rHBQbXWl5H51uEoiN5mmkBA=; b=Hjb3rwnvy5J/tPYCYlfzXFAHL78C/DTsPOojbblL2x0Xffy+7PYL5Rb7blti/r1KrR plYEZCrFvBqOEfp6RMVTiHGA6R/fxD5Yx9Zyld2znG2I9WXnFDcSEupBY34xsc0wpXFa fz2mRLdr5FUSk0PfX+/uS1MazWafd9vv2TuTMHnNAIofjusC2OtImls3v7Q8Ei/Qcpgh BtLnyudfIzkKv0BivTAfoUVHPPyNesVTvawOKVN0m2CgtcoTGghRSHQMzF3m329cS5d2 UaFH7elxAcJ4JaRA6kGhbO+8U0/08DZwNHGOw3TAwiLtJ09VusNCu2hOOUy8bXtZchQH /rZw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=8ytIn/f+EUf0Gut52ap1rHBQbXWl5H51uEoiN5mmkBA=; b=OIhAOaAZuD5Rg5GYf842V7gNBgPsmJAKsfoeYzVJ7hduuMlCDPuZn6cQ+NhNi7ocSY 7VxzMwHhdQI+IXwUYhj3s+aZkPaBIM2eCogYGHJpWbnUdu9MfU8AohzetaXF5k0QSvnL az1XtKCSoHW0yrd9ge+QQtK4Vit1fNIlRyGF/7DSmnD46qR1BYb4lujE9QcWVqQnnkxg 6RXyN3Um1iEGF6NBWefuzWOjlE9M3uA6rErtKvMWf1zdAxEuP3ugNoMsdQI/QYp4aXEl Ui5Z6+i37ekE/xXK0gMFpbYaPSl59fRnBaXwersehnMm8TLLniiRILJbAbzh/4T71GZp 9CUw== X-Gm-Message-State: ANoB5pmuJqvMgu6CO8dDTtdRROwEMc6is7aERn52YBdm98KhuMq3NAip YQlKWVefTXmdnkNVuXaf6ySuQA== X-Google-Smtp-Source: AA0mqf5/1fc/ay9S0qpZ54QCPXaSLIzjDWNemj6uxkgk8CUEeEG5LDZOPSSj+ws62hfg6uC4hghirg== X-Received: by 2002:adf:f34b:0:b0:240:e14:cfa8 with SMTP id e11-20020adff34b000000b002400e14cfa8mr11819668wrp.63.1668547157217; Tue, 15 Nov 2022 13:19:17 -0800 (PST) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id n41-20020a05600c502900b003c65c9a36dfsm17201487wmr.48.2022.11.15.13.19.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Nov 2022 13:19:16 -0800 (PST) From: Dmitry Safonov To: linux-kernel@vger.kernel.org, David Ahern , Eric Dumazet , Peter Zijlstra Cc: Dmitry Safonov , Ard Biesheuvel , Bob Gilligan , "David S. Miller" , Dmitry Safonov <0x7f454c46@gmail.com>, Francesco Ruggeri , Hideaki YOSHIFUJI , Jakub Kicinski , Jason Baron , Josh Poimboeuf , Paolo Abeni , Salam Noureddine , Steven Rostedt , netdev@vger.kernel.org Subject: [PATCH v4 3/5] net/tcp: Disable TCP-MD5 static key on tcp_md5sig_info destruction Date: Tue, 15 Nov 2022 21:19:03 +0000 Message-Id: <20221115211905.1685426-4-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221115211905.1685426-1-dima@arista.com> References: <20221115211905.1685426-1-dima@arista.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org To do that, separate two scenarios: - where it's the first MD5 key on the system, which means that enabling of the static key may need to sleep; - copying of an existing key from a listening socket to the request socket upon receiving a signed TCP segment, where static key was already enabled (when the key was added to the listening socket). Now the life-time of the static branch for TCP-MD5 is until: - last tcp_md5sig_info is destroyed - last socket in time-wait state with MD5 key is closed. Which means that after all sockets with TCP-MD5 keys are gone, the system gets back the performance of disabled md5-key static branch. While at here, provide static_key_fast_inc() helper that does ref counter increment in atomic fashion (without grabbing cpus_read_lock() on CONFIG_JUMP_LABEL=y). This is needed to add a new user for a static_key when the caller controls the lifetime of another user. Signed-off-by: Dmitry Safonov Acked-by: Jakub Kicinski --- include/linux/jump_label.h | 4 ++- include/net/tcp.h | 10 ++++-- kernel/jump_label.c | 3 +- net/ipv4/tcp.c | 5 +-- net/ipv4/tcp_ipv4.c | 69 +++++++++++++++++++++++++++++++------- net/ipv4/tcp_minisocks.c | 16 ++++++--- net/ipv4/tcp_output.c | 4 +-- net/ipv6/tcp_ipv6.c | 10 +++--- 8 files changed, 87 insertions(+), 34 deletions(-) diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index c0a02d4c2ea2..f3fc5081cae6 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -225,6 +225,7 @@ extern bool arch_jump_label_transform_queue(struct jump_entry *entry, extern void arch_jump_label_transform_apply(void); extern int jump_label_text_reserved(void *start, void *end); extern bool static_key_slow_inc(struct static_key *key); +extern bool static_key_fast_inc_not_negative(struct static_key *key); extern void static_key_slow_dec(struct static_key *key); extern bool static_key_slow_inc_cpuslocked(struct static_key *key); extern void static_key_slow_dec_cpuslocked(struct static_key *key); @@ -278,7 +279,7 @@ static __always_inline bool static_key_true(struct static_key *key) return false; } -static inline bool static_key_slow_inc(struct static_key *key) +static inline bool static_key_fast_inc_not_negative(struct static_key *key) { int v; @@ -294,6 +295,7 @@ static inline bool static_key_slow_inc(struct static_key *key) } while (!likely(atomic_try_cmpxchg(&key->enabled, &v, v + 1))); return true; } +#define static_key_slow_inc(key) static_key_fast_inc_not_negative(key) static inline void static_key_slow_dec(struct static_key *key) { diff --git a/include/net/tcp.h b/include/net/tcp.h index 14d45661a84d..a0cdf013782a 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1675,7 +1675,11 @@ int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key, const struct sock *sk, const struct sk_buff *skb); int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags, - const u8 *newkey, u8 newkeylen, gfp_t gfp); + const u8 *newkey, u8 newkeylen); +int tcp_md5_key_copy(struct sock *sk, const union tcp_md5_addr *addr, + int family, u8 prefixlen, int l3index, + struct tcp_md5sig_key *key); + int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags); struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk, @@ -1683,7 +1687,7 @@ struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk, #ifdef CONFIG_TCP_MD5SIG #include -extern struct static_key_false tcp_md5_needed; +extern struct static_key_false_deferred tcp_md5_needed; struct tcp_md5sig_key *__tcp_md5_do_lookup(const struct sock *sk, int l3index, const union tcp_md5_addr *addr, int family); @@ -1691,7 +1695,7 @@ static inline struct tcp_md5sig_key * tcp_md5_do_lookup(const struct sock *sk, int l3index, const union tcp_md5_addr *addr, int family) { - if (!static_branch_unlikely(&tcp_md5_needed)) + if (!static_branch_unlikely(&tcp_md5_needed.key)) return NULL; return __tcp_md5_do_lookup(sk, l3index, addr, family); } diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 677a6674c130..32c785f5d2b1 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -123,7 +123,7 @@ EXPORT_SYMBOL_GPL(static_key_count); * * Returns true if the increment was done. */ -static bool static_key_fast_inc_not_negative(struct static_key *key) +bool static_key_fast_inc_not_negative(struct static_key *key) { int v; @@ -142,6 +142,7 @@ static bool static_key_fast_inc_not_negative(struct static_key *key) return true; } +EXPORT_SYMBOL_GPL(static_key_fast_inc_not_negative); bool static_key_slow_inc_cpuslocked(struct static_key *key) { diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 54836a6b81d6..07a73c9b49da 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4460,11 +4460,8 @@ bool tcp_alloc_md5sig_pool(void) if (unlikely(!READ_ONCE(tcp_md5sig_pool_populated))) { mutex_lock(&tcp_md5sig_mutex); - if (!tcp_md5sig_pool_populated) { + if (!tcp_md5sig_pool_populated) __tcp_alloc_md5sig_pool(); - if (tcp_md5sig_pool_populated) - static_branch_inc(&tcp_md5_needed); - } mutex_unlock(&tcp_md5sig_mutex); } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index fae80b1a1796..4bdb6e1ecaf3 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1064,7 +1064,7 @@ static void tcp_v4_reqsk_destructor(struct request_sock *req) * We need to maintain these in the sk structure. */ -DEFINE_STATIC_KEY_FALSE(tcp_md5_needed); +DEFINE_STATIC_KEY_DEFERRED_FALSE(tcp_md5_needed, HZ); EXPORT_SYMBOL(tcp_md5_needed); static bool better_md5_match(struct tcp_md5sig_key *old, struct tcp_md5sig_key *new) @@ -1177,9 +1177,6 @@ static int tcp_md5sig_info_add(struct sock *sk, gfp_t gfp) struct tcp_sock *tp = tcp_sk(sk); struct tcp_md5sig_info *md5sig; - if (rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk))) - return 0; - md5sig = kmalloc(sizeof(*md5sig), gfp); if (!md5sig) return -ENOMEM; @@ -1191,9 +1188,9 @@ static int tcp_md5sig_info_add(struct sock *sk, gfp_t gfp) } /* This can be called on a newly created socket, from other files */ -int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, - int family, u8 prefixlen, int l3index, u8 flags, - const u8 *newkey, u8 newkeylen, gfp_t gfp) +static int __tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, + int family, u8 prefixlen, int l3index, u8 flags, + const u8 *newkey, u8 newkeylen, gfp_t gfp) { /* Add Key to the list */ struct tcp_md5sig_key *key; @@ -1220,9 +1217,6 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, return 0; } - if (tcp_md5sig_info_add(sk, gfp)) - return -ENOMEM; - md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk)); @@ -1246,8 +1240,57 @@ int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, hlist_add_head_rcu(&key->node, &md5sig->head); return 0; } + +int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, + int family, u8 prefixlen, int l3index, u8 flags, + const u8 *newkey, u8 newkeylen) +{ + struct tcp_sock *tp = tcp_sk(sk); + + if (!rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk))) { + if (tcp_md5sig_info_add(sk, GFP_KERNEL)) + return -ENOMEM; + + if (!static_branch_inc(&tcp_md5_needed.key)) { + struct tcp_md5sig_info *md5sig = tp->md5sig_info; + + rcu_assign_pointer(tp->md5sig_info, NULL); + kfree_rcu(md5sig); + return -EUSERS; + } + } + + return __tcp_md5_do_add(sk, addr, family, prefixlen, l3index, flags, + newkey, newkeylen, GFP_KERNEL); +} EXPORT_SYMBOL(tcp_md5_do_add); +int tcp_md5_key_copy(struct sock *sk, const union tcp_md5_addr *addr, + int family, u8 prefixlen, int l3index, + struct tcp_md5sig_key *key) +{ + struct tcp_sock *tp = tcp_sk(sk); + + if (!rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk))) { + if (tcp_md5sig_info_add(sk, sk_gfp_mask(sk, GFP_ATOMIC))) + return -ENOMEM; + + if (!static_key_fast_inc_not_negative(&tcp_md5_needed.key.key)) { + struct tcp_md5sig_info *md5sig = tp->md5sig_info; + + net_warn_ratelimited("Too many TCP-MD5 keys in the system\n"); + rcu_assign_pointer(tp->md5sig_info, NULL); + kfree_rcu(md5sig); + return -EUSERS; + } + } + + return __tcp_md5_do_add(sk, addr, family, prefixlen, l3index, + key->flags, key->key, key->keylen, + sk_gfp_mask(sk, GFP_ATOMIC)); +} +EXPORT_SYMBOL(tcp_md5_key_copy); + int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family, u8 prefixlen, int l3index, u8 flags) { @@ -1334,7 +1377,7 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, int optname, return -EINVAL; return tcp_md5_do_add(sk, addr, AF_INET, prefixlen, l3index, flags, - cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); + cmd.tcpm_key, cmd.tcpm_keylen); } static int tcp_v4_md5_hash_headers(struct tcp_md5sig_pool *hp, @@ -1591,8 +1634,7 @@ struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, * memory, then we end up not copying the key * across. Shucks. */ - tcp_md5_do_add(newsk, addr, AF_INET, 32, l3index, key->flags, - key->key, key->keylen, GFP_ATOMIC); + tcp_md5_key_copy(newsk, addr, AF_INET, 32, l3index, key); sk_gso_disable(newsk); } #endif @@ -2284,6 +2326,7 @@ void tcp_v4_destroy_sock(struct sock *sk) tcp_clear_md5_list(sk); kfree_rcu(rcu_dereference_protected(tp->md5sig_info, 1), rcu); tp->md5sig_info = NULL; + static_branch_slow_dec_deferred(&tcp_md5_needed); } #endif diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index c375f603a16c..50f91c10eb7b 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -291,13 +291,19 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) */ do { tcptw->tw_md5_key = NULL; - if (static_branch_unlikely(&tcp_md5_needed)) { + if (static_branch_unlikely(&tcp_md5_needed.key)) { struct tcp_md5sig_key *key; key = tp->af_specific->md5_lookup(sk, sk); if (key) { tcptw->tw_md5_key = kmemdup(key, sizeof(*key), GFP_ATOMIC); - BUG_ON(tcptw->tw_md5_key && !tcp_alloc_md5sig_pool()); + if (!tcptw->tw_md5_key) + break; + BUG_ON(!tcp_alloc_md5sig_pool()); + if (!static_key_fast_inc_not_negative(&tcp_md5_needed.key.key)) { + kfree(tcptw->tw_md5_key); + tcptw->tw_md5_key = NULL; + } } } } while (0); @@ -337,11 +343,13 @@ EXPORT_SYMBOL(tcp_time_wait); void tcp_twsk_destructor(struct sock *sk) { #ifdef CONFIG_TCP_MD5SIG - if (static_branch_unlikely(&tcp_md5_needed)) { + if (static_branch_unlikely(&tcp_md5_needed.key)) { struct tcp_timewait_sock *twsk = tcp_twsk(sk); - if (twsk->tw_md5_key) + if (twsk->tw_md5_key) { kfree_rcu(twsk->tw_md5_key, rcu); + static_branch_slow_dec_deferred(&tcp_md5_needed); + } } #endif } diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index c69f4d966024..86e71c8c76bc 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -766,7 +766,7 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb, *md5 = NULL; #ifdef CONFIG_TCP_MD5SIG - if (static_branch_unlikely(&tcp_md5_needed) && + if (static_branch_unlikely(&tcp_md5_needed.key) && rcu_access_pointer(tp->md5sig_info)) { *md5 = tp->af_specific->md5_lookup(sk, sk); if (*md5) { @@ -922,7 +922,7 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb *md5 = NULL; #ifdef CONFIG_TCP_MD5SIG - if (static_branch_unlikely(&tcp_md5_needed) && + if (static_branch_unlikely(&tcp_md5_needed.key) && rcu_access_pointer(tp->md5sig_info)) { *md5 = tp->af_specific->md5_lookup(sk, sk); if (*md5) { diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 2a3f9296df1e..3e3bdc120fc8 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -677,12 +677,11 @@ static int tcp_v6_parse_md5_keys(struct sock *sk, int optname, if (ipv6_addr_v4mapped(&sin6->sin6_addr)) return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], AF_INET, prefixlen, l3index, flags, - cmd.tcpm_key, cmd.tcpm_keylen, - GFP_KERNEL); + cmd.tcpm_key, cmd.tcpm_keylen); return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr, AF_INET6, prefixlen, l3index, flags, - cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); + cmd.tcpm_key, cmd.tcpm_keylen); } static int tcp_v6_md5_hash_headers(struct tcp_md5sig_pool *hp, @@ -1382,9 +1381,8 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff * * memory, then we end up not copying the key * across. Shucks. */ - tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, - AF_INET6, 128, l3index, key->flags, key->key, key->keylen, - sk_gfp_mask(sk, GFP_ATOMIC)); + tcp_md5_key_copy(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, + AF_INET6, 128, l3index, key); } #endif From patchwork Tue Nov 15 21:19:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13044185 X-Patchwork-Delegate: kuba@kernel.org 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 41875C43217 for ; Tue, 15 Nov 2022 21:20:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231815AbiKOVUI (ORCPT ); Tue, 15 Nov 2022 16:20:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45406 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231939AbiKOVTz (ORCPT ); Tue, 15 Nov 2022 16:19:55 -0500 Received: from mail-wm1-x330.google.com (mail-wm1-x330.google.com [IPv6:2a00:1450:4864:20::330]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4AA842315D for ; Tue, 15 Nov 2022 13:19:46 -0800 (PST) Received: by mail-wm1-x330.google.com with SMTP id m7-20020a05600c090700b003cf8a105d9eso49072wmp.5 for ; Tue, 15 Nov 2022 13:19:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=O4voqyqcbC1mGHkdqsComHC8t7xgb7NXhy1RVgGBazg=; b=YwulyWQxFTlK3VttrI24bnCHMwwrAe/1KahE3WGjJJ8WL+Mn6T6KYdNtBFYzBrXVNe oixrbUxkVsQ8hKzZKAfCUR8e2gU1/zZh4Znnn/m6JVn16jMs4aHIKoN5e+ItM+O/QD5q nwnw6L5a838kRS4xWLMxlqGhgJdX+okXu9G8UHEhOiJP+qOfM6byfBjbj5ON47N2Mb9h OAcL8RGAxgWeGT+AJ2stN7SFs2h1oZIDkT2R0PRD11+TMig1X6O7XBR3fBk2Voggbsa+ uS5HQKa+C2PmcW5c7nbn/q/qnwb2RescA5UjxaKRR3PwsrIxhda1rrCRZpUtpX01nn7+ Bb0w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=O4voqyqcbC1mGHkdqsComHC8t7xgb7NXhy1RVgGBazg=; b=jg2D1U1IHuTbH3a30GAShhuZ9CFJ+LeeKKL+MnKGWtEzd+rubpiCC/ZIWg7/udEvr9 pLA3ke4YZTxYe/XTtHIbSNERHkWIyFrZlnjfsBkZk3MglTcCdag+FHgvwa1Gtrx8DXpL F/xSHD/O0T1wCnZj8GniqBBI05UMHHswJrWWkWavmO+NwX+wqJtXOFSE3OgsRSabb5Km gNI4IlBlxSHFTb78Lp3TrrmxCbrqD9522ZJj6yxrQLMqS23UKaCfoVS0aio83snG0OI8 kScher/NFXYfFle+WgVjlgVWpdruom2NcJcA0gTceG6jvqzwfakyn+6aSuDUwOJX9h9S zrGg== X-Gm-Message-State: ANoB5pkqobFwdTiGn450vFJ5GyakOmAq4Z4UJUbQBODAdVnR0srA/SQ9 YtQOb2gOd6hnXmCFGYk4YLKoYQ== X-Google-Smtp-Source: AA0mqf7aA0CcV03VaLTA+Oml/BIjII7CGjdUTmxKQVmCFUrp5XXH63ryVWRQy3gyvMj0WyCKfRYNzQ== X-Received: by 2002:a05:600c:188a:b0:3cf:8e62:f769 with SMTP id x10-20020a05600c188a00b003cf8e62f769mr147561wmp.52.1668547158791; Tue, 15 Nov 2022 13:19:18 -0800 (PST) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id n41-20020a05600c502900b003c65c9a36dfsm17201487wmr.48.2022.11.15.13.19.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Nov 2022 13:19:18 -0800 (PST) From: Dmitry Safonov To: linux-kernel@vger.kernel.org, David Ahern , Eric Dumazet , Peter Zijlstra Cc: Dmitry Safonov , Ard Biesheuvel , Bob Gilligan , "David S. Miller" , Dmitry Safonov <0x7f454c46@gmail.com>, Francesco Ruggeri , Hideaki YOSHIFUJI , Jakub Kicinski , Jason Baron , Josh Poimboeuf , Paolo Abeni , Salam Noureddine , Steven Rostedt , netdev@vger.kernel.org Subject: [PATCH v4 4/5] net/tcp: Do cleanup on tcp_md5_key_copy() failure Date: Tue, 15 Nov 2022 21:19:04 +0000 Message-Id: <20221115211905.1685426-5-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221115211905.1685426-1-dima@arista.com> References: <20221115211905.1685426-1-dima@arista.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org If the kernel was short on (atomic) memory and failed to allocate it - don't proceed to creation of request socket. Otherwise the socket would be unsigned and userspace likely doesn't expect that the TCP is not MD5-signed anymore. Signed-off-by: Dmitry Safonov --- net/ipv4/tcp_ipv4.c | 9 ++------- net/ipv6/tcp_ipv6.c | 15 ++++++++------- 2 files changed, 10 insertions(+), 14 deletions(-) diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 4bdb6e1ecaf3..deabf3309865 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1628,13 +1628,8 @@ struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, addr = (union tcp_md5_addr *)&newinet->inet_daddr; key = tcp_md5_do_lookup(sk, l3index, addr, AF_INET); if (key) { - /* - * We're using one, so create a matching key - * on the newsk structure. If we fail to get - * memory, then we end up not copying the key - * across. Shucks. - */ - tcp_md5_key_copy(newsk, addr, AF_INET, 32, l3index, key); + if (tcp_md5_key_copy(newsk, addr, AF_INET, 32, l3index, key)) + goto put_and_exit; sk_gso_disable(newsk); } #endif diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 3e3bdc120fc8..64788cfbefc7 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1376,13 +1376,14 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff * /* Copy over the MD5 key from the original socket */ key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr, l3index); if (key) { - /* We're using one, so create a matching key - * on the newsk structure. If we fail to get - * memory, then we end up not copying the key - * across. Shucks. - */ - tcp_md5_key_copy(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, - AF_INET6, 128, l3index, key); + const union tcp_md5_addr *addr; + + addr = (union tcp_md5_addr *)&newsk->sk_v6_daddr; + if (tcp_md5_key_copy(newsk, addr, AF_INET6, 128, l3index, key)) { + inet_csk_prepare_forced_close(newsk); + tcp_done(newsk); + goto out; + } } #endif From patchwork Tue Nov 15 21:19:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13044182 X-Patchwork-Delegate: kuba@kernel.org 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 DF381C43217 for ; Tue, 15 Nov 2022 21:20:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232244AbiKOVUA (ORCPT ); Tue, 15 Nov 2022 16:20:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231322AbiKOVTv (ORCPT ); Tue, 15 Nov 2022 16:19:51 -0500 Received: from mail-wr1-x42f.google.com (mail-wr1-x42f.google.com [IPv6:2a00:1450:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FB3B23174 for ; Tue, 15 Nov 2022 13:19:46 -0800 (PST) Received: by mail-wr1-x42f.google.com with SMTP id l14so26551095wrw.2 for ; Tue, 15 Nov 2022 13:19:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=QrKEt8xGpN11qf/n3/wg8niAJAFvn6hZvrWVQxWQt4g=; b=fiVUvzanF1MNolL7T+CltA94XNZSW4VdbdBPdch82XQjipq8aq+Yi7VAnWgnD8s2e+ Lz8sQqgJ3eN+BHq+K8sXMQCxu2Irl6SBI0LizkFlYe0Ft367ENJzWfhc97792IVACQaP AnnteECEFW7PpNpaV/KlsRjvPC0XqXInp/eAjn1lYbyg6ba4N1l5CYutKCfWTpNgj1CM e7xGdPoqvSpco8RP05u/yzoIx/33Htfpa7rs8/ZItQKtNr8zu6GlsuliasvnGGcNdAZa lw7+8IUiTnxVekNcbDELxNh95fQKzP30cc1L3qf2ZEKXs9UZc5mOKirVB560+fXJjF8X pYzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=QrKEt8xGpN11qf/n3/wg8niAJAFvn6hZvrWVQxWQt4g=; b=1HbLu9Ze2ZEkNhvOxx5OSRm86nnijxh8apR5Cy8cyBIR5/ZQ/JM6+lSqb+10MOy0B2 t1ApW1KipEN5sDIYu35lSpIj/FJ5VHQ3rBIfQte76RaWxwZS3tXj5EHU/48x/MBmcojS H5epqHiTkS03wI3RMF8BuzmqHfC6NIxwLml5L396UYCeEGl6q7U398lDI2XAopyvYPsM tlnUihwjlvhCfOPUlPGcO6GKZZJtqVAUEQEVQvrHhNLDsGlHYwwE+QXLc6vKT+qjFr1x Tw9XlOzeH+tQAvU8RjFe9qeBVQoIjARdk1987xp+yetSO3nyW+L91QWlZ24hRzWZJBv4 sMoQ== X-Gm-Message-State: ANoB5pmRQe3JxMDMH/hhdG7OXEfeG5bwpbKAJPOeCgmSsjXAvOqIjA9f VATLzo/1UxuED06g6YyX4vydkQ== X-Google-Smtp-Source: AA0mqf6CV7LJUbYPSpLTBC3OLtXhrCWbq8SAxnpH7zuPrSXasJey8qmnKv7HkVUFLJDAiiJN+Va78w== X-Received: by 2002:adf:f211:0:b0:23a:43b7:cdd5 with SMTP id p17-20020adff211000000b0023a43b7cdd5mr11857847wro.387.1668547160245; Tue, 15 Nov 2022 13:19:20 -0800 (PST) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id n41-20020a05600c502900b003c65c9a36dfsm17201487wmr.48.2022.11.15.13.19.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Nov 2022 13:19:19 -0800 (PST) From: Dmitry Safonov To: linux-kernel@vger.kernel.org, David Ahern , Eric Dumazet , Peter Zijlstra Cc: Dmitry Safonov , Ard Biesheuvel , Bob Gilligan , "David S. Miller" , Dmitry Safonov <0x7f454c46@gmail.com>, Francesco Ruggeri , Hideaki YOSHIFUJI , Jakub Kicinski , Jason Baron , Josh Poimboeuf , Paolo Abeni , Salam Noureddine , Steven Rostedt , netdev@vger.kernel.org Subject: [PATCH v4 5/5] net/tcp: Separate initialization of twsk Date: Tue, 15 Nov 2022 21:19:05 +0000 Message-Id: <20221115211905.1685426-6-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221115211905.1685426-1-dima@arista.com> References: <20221115211905.1685426-1-dima@arista.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Convert BUG_ON() to WARN_ON_ONCE() and warn as well for unlikely static key int overflow error-path. Signed-off-by: Dmitry Safonov --- net/ipv4/tcp_minisocks.c | 61 +++++++++++++++++++++++----------------- 1 file changed, 35 insertions(+), 26 deletions(-) diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 50f91c10eb7b..1cfafad9ba29 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -240,6 +240,40 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb, } EXPORT_SYMBOL(tcp_timewait_state_process); +static void tcp_time_wait_init(struct sock *sk, struct tcp_timewait_sock *tcptw) +{ +#ifdef CONFIG_TCP_MD5SIG + const struct tcp_sock *tp = tcp_sk(sk); + struct tcp_md5sig_key *key; + + /* + * The timewait bucket does not have the key DB from the + * sock structure. We just make a quick copy of the + * md5 key being used (if indeed we are using one) + * so the timewait ack generating code has the key. + */ + tcptw->tw_md5_key = NULL; + if (!static_branch_unlikely(&tcp_md5_needed.key)) + return; + + key = tp->af_specific->md5_lookup(sk, sk); + if (key) { + tcptw->tw_md5_key = kmemdup(key, sizeof(*key), GFP_ATOMIC); + if (!tcptw->tw_md5_key) + return; + if (!tcp_alloc_md5sig_pool()) + goto out_free; + if (!static_key_fast_inc_not_negative(&tcp_md5_needed.key.key)) + goto out_free; + } + return; +out_free: + WARN_ON_ONCE(1); + kfree(tcptw->tw_md5_key); + tcptw->tw_md5_key = NULL; +#endif +} + /* * Move a socket to time-wait or dead fin-wait-2 state. */ @@ -282,32 +316,7 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) } #endif -#ifdef CONFIG_TCP_MD5SIG - /* - * The timewait bucket does not have the key DB from the - * sock structure. We just make a quick copy of the - * md5 key being used (if indeed we are using one) - * so the timewait ack generating code has the key. - */ - do { - tcptw->tw_md5_key = NULL; - if (static_branch_unlikely(&tcp_md5_needed.key)) { - struct tcp_md5sig_key *key; - - key = tp->af_specific->md5_lookup(sk, sk); - if (key) { - tcptw->tw_md5_key = kmemdup(key, sizeof(*key), GFP_ATOMIC); - if (!tcptw->tw_md5_key) - break; - BUG_ON(!tcp_alloc_md5sig_pool()); - if (!static_key_fast_inc_not_negative(&tcp_md5_needed.key.key)) { - kfree(tcptw->tw_md5_key); - tcptw->tw_md5_key = NULL; - } - } - } - } while (0); -#endif + tcp_time_wait_init(sk, tcptw); /* Get the TIME_WAIT timeout firing. */ if (timeo < rto)