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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 v6 1/5] jump_label: Prevent key->enabled int overflow Date: Wed, 23 Nov 2022 17:38:55 +0000 Message-Id: <20221123173859.473629-2-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123173859.473629-1-dima@arista.com> References: <20221123173859.473629-1-dima@arista.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1750309757095340580?= X-GMAIL-MSGID: =?utf-8?q?1750309757095340580?= 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 Acked-by: Jakub Kicinski Acked-by: Peter Zijlstra (Intel) --- include/linux/jump_label.h | 21 +++++++++++--- kernel/jump_label.c | 56 ++++++++++++++++++++++++++++++-------- 2 files changed, 61 insertions(+), 16 deletions(-) diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index 570831ca9951..4e968ebadce6 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -224,9 +224,10 @@ 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 bool static_key_fast_inc_not_disabled(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); @@ -278,11 +279,23 @@ 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_fast_inc_not_disabled(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; } +#define static_key_slow_inc(key) static_key_fast_inc_not_disabled(key) 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..d9c822bbffb8 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -113,9 +113,40 @@ 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_disabled - 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. Unlike refcount_t the ref counter + * is not saturated, but will fail to increment on overflow. + */ +bool static_key_fast_inc_not_disabled(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; +} +EXPORT_SYMBOL_GPL(static_key_fast_inc_not_disabled); + +bool static_key_slow_inc_cpuslocked(struct static_key *key) +{ lockdep_assert_cpus_held(); /* @@ -124,15 +155,9 @@ 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_disabled(key)) + return true; jump_label_lock(); if (atomic_read(&key->enabled) == 0) { @@ -144,16 +169,23 @@ 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_disabled(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 Wed Nov 23 17:38:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 25095 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:f944:0:0:0:0:0 with SMTP id q4csp2930596wrr; Wed, 23 Nov 2022 09:44:26 -0800 (PST) X-Google-Smtp-Source: AA0mqf4JWgUUOPbX5sI0tAJN7fidZKjsIyjQYjOjX7buuIMCK6OpdwulPqzXpUnJy9PJWCcv6hDH X-Received: by 2002:a17:906:edbd:b0:783:5326:90e5 with SMTP id sa29-20020a170906edbd00b00783532690e5mr4670313ejb.374.1669225466523; Wed, 23 Nov 2022 09:44:26 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1669225466; cv=none; d=google.com; s=arc-20160816; b=z3FpVYiCfF+DrvVSBoQboDcp1XsajT2oqaL43DkRpHsYyURUX9DBffon52XkVPvN5O pzzqPtlqw6EeTMsxsyHpFOgGYnZMHmE/bwXzPdWvTZirJ/v6XsYHdKO5Xx5Ut2CPuzYt fo7cK/UUKTkJrCM5t7z1GoY68RTm4dLSIkar8uZ67jrJv1ezVIctCFBcRJJqgMSZ6rkh kcBudtcykC/tTsFCDNtMILC/UP3pZ4K5u5+xXLcJRwrp454fPbyHv2KVMGkNKAzz5wNe AkiNGOIdOUlaiBng5Nu4HDWCLXjGYuYY6nj2XPO3Sae5tWhiXTmAa4AJhaGJg4mc3sPV fZmg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=olRr0NxHpe7WEA5OvPe/+zbTbmND6iy3IpcPyCocNn4=; b=v8RigzEumGMARNvwzEQNaVUJ0jAScGdYxDhoH4EELlH+GN99L7WNAasRovaNyjOsZv 0yVcJPwhR7sM9xlPneP3MTLseG58SeX0aKrEI0FKNSLQrpVJEwak5othQt3IzvvoYl2k EhM9PsanBzBED3jaj3djdWwLRHZp0Ll9E4RUYVyTn4y2xkI9O2VgF4ktigAuMkkrrRTH 8Jtgmqwzq/nture1wA08vFK+kJn/Ruqbe7QEIrh0/DA708B3jebhgt89sjrYw9nvmv6A mBA19sFXYPIAbeiGVTyWOm4FaTMm3pXrQogjLnnguFu6Nuoj0GPbkuBMbMRfZSzicNFn 38Gw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@arista.com header.s=google header.b=MGZ7Qykb; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=arista.com Received: from out1.vger.email (out1.vger.email. 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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 v6 2/5] net/tcp: Separate tcp_md5sig_info allocation into tcp_md5sig_info_add() Date: Wed, 23 Nov 2022 17:38:56 +0000 Message-Id: <20221123173859.473629-3-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123173859.473629-1-dima@arista.com> References: <20221123173859.473629-1-dima@arista.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1750309763016159698?= X-GMAIL-MSGID: =?utf-8?q?1750309763016159698?= 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 Acked-by: Jakub Kicinski --- 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 f0343538d1f8..2d76d50b8ae8 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 Wed Nov 23 17:38:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 25096 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:f944:0:0:0:0:0 with SMTP id q4csp2930645wrr; Wed, 23 Nov 2022 09:44:34 -0800 (PST) X-Google-Smtp-Source: AA0mqf48UdlEoFlx/khjInRFSGdkLtjHsa+gi76rP0rQYYM0Pxxgz1MIdwNg93UDG7SClRCK9Uvw X-Received: by 2002:a05:6402:4d6:b0:458:789b:c1b0 with SMTP id n22-20020a05640204d600b00458789bc1b0mr15906705edw.89.1669225474561; Wed, 23 Nov 2022 09:44:34 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1669225474; cv=none; d=google.com; s=arc-20160816; b=GNycumZ3NyUvF4hF9e7iHsbiOMxl3Aq+TmsNL0JJKRUWhQmNJdft+Iytcabvujt7Kl MQbGe/VHNARDV1SlY8ZqsuVHb3qRSUaWdPEsDsJUV6S42hdIhKuFjEvjokqxyDyIt8WM sLPvWH5LMvBhBX/ORejtC619njpThnjdjMOptC9xiA7WdB4gBEMR0GZjrK4Hcca/zb/M +GK6G7S7cj6bUDQHRWGvM0mwH8jUERZVJTtPUiDryjRc9cdORTA44KjyyqnMaGs3YB7m TXhKJgLOmo4INX0O+llfsy0oRHa6TIys4zoedSqF+sssJSDXgCIHJ3x6KoLQhxCjFepA tYig== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=QJl43J7LXNMRLHYBO6ueXn5ohHHf1zFt6off0HzUS64=; b=ZNujtq8/LECKhCqFcBeQ+zn+OR/8Lxzi6b8g+8SYkY2+dO0o3ue16olIMl8fiIWity Y651ChakttnkRBuMPeKtpyGn/m2fv+PE2oZDJvBaG2iGycS+NbkGDUSFHKX97BnVYEIy pt/3a+Xtlb2HfKwQX+w2voDSOxbCuP4v8zLFAG33/cl54agJfQiNeT6O5VCciXM6XI1K WlCtjTCGiQHzcM8e1//YOaSWl39FD30sBUYRyhul3Ztenp33hzMJcwmsa1Lds9rjY4Wi 0QdAwg1KwoxLIkW4ob0mGASIxj75lf6YoeRUzCUc9gvs2WYB72gv7bhS6yRbcZrxIwOF uCYw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@arista.com header.s=google header.b=O+P3+NPB; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=arista.com Received: from out1.vger.email (out1.vger.email. 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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 v6 3/5] net/tcp: Disable TCP-MD5 static key on tcp_md5sig_info destruction Date: Wed, 23 Nov 2022 17:38:57 +0000 Message-Id: <20221123173859.473629-4-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123173859.473629-1-dima@arista.com> References: <20221123173859.473629-1-dima@arista.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1750309771191078056?= X-GMAIL-MSGID: =?utf-8?q?1750309771191078056?= 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 Reviewed-by: Eric Dumazet --- include/net/tcp.h | 10 ++++-- net/ipv4/tcp.c | 5 +-- net/ipv4/tcp_ipv4.c | 71 ++++++++++++++++++++++++++++++++-------- net/ipv4/tcp_minisocks.c | 16 ++++++--- net/ipv4/tcp_output.c | 4 +-- net/ipv6/tcp_ipv6.c | 10 +++--- 6 files changed, 84 insertions(+), 32 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 6b814e788f00..f925377066fe 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/net/ipv4/tcp.c b/net/ipv4/tcp.c index 4a69c5fcfedc..267406f199bc 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4465,11 +4465,8 @@ 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 2d76d50b8ae8..2ae6a061f36e 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 +1240,59 @@ 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; + + md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk)); + 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_disabled(&tcp_md5_needed.key.key)) { + struct tcp_md5sig_info *md5sig; + + md5sig = rcu_dereference_protected(tp->md5sig_info, lockdep_sock_is_held(sk)); + 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 +1379,7 @@ 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 +1636,7 @@ 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 +2328,7 @@ 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..6908812d50d3 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_disabled(&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 894410dc9293..71d01cf3c13e 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 f676be14e6b6..83304d6a6bd0 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 Wed Nov 23 17:38:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 25097 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:f944:0:0:0:0:0 with SMTP id q4csp2930789wrr; Wed, 23 Nov 2022 09:44:55 -0800 (PST) X-Google-Smtp-Source: AA0mqf6/AAdjO9QPAAEp6lex5sdPTMOt/trj6aknTVsu93YLS4aJ7ab4o/n6RDGGRd5A0DIn5jSQ X-Received: by 2002:a17:906:f281:b0:7ae:3b9e:1d8a with SMTP id gu1-20020a170906f28100b007ae3b9e1d8amr23452031ejb.581.1669225494730; Wed, 23 Nov 2022 09:44:54 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1669225494; cv=none; d=google.com; s=arc-20160816; b=PXEHduDqCXZM6J5NreLmd28GoDMkdyhLm1BWWiyto+oWCmgSgYCe0rQAnYMqkR09GW 5FDZF+sRSfvSzIjR7UPd8BMg3r+efjKpArhVprFrQpmNDl/GY3tktTZC2p/fDi88Qm+y 3Y85DNP3FXuiBz6iqCHWPhd3wYxX8yzPGf25u+TNL+Uq61TR0uW6tRydOhQqcsfnW063 XjHbXnJthzYqgQKHhW//CKtsKcaVj7ZTjrIo2BbgOk6zQ39E2e48AwEswE3vqvbL0Dg4 xBWZ9TomkoWCVhmHZ8QoGb54NxlmHoiaL8PYLGWCOD1qZxfgsBGxanXHA51mZ9eia4uV /nTw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=SmDkIrBVfUMbGOBltM7PoGg9g03wcI36X1ZwAu/jynQ=; b=pX4wgsDQTbbnJro8GhGiSIWfxwthX62JulP9Zwrq+i6cA9RIZj8GWIPQVCz6cq4Yto 245kiLEGSnFZXRywpdoumd5N6qQcVOOBNYtfVHYvullQTEPwyp0FAgvB1lNSVgvnPE+q H8rIFp83NoDvQBmpNeV9ovK1/v7nVhxaJQ84EtReLx0oCJrnrbcGVrtPzIuqXr2NNel/ XQWV/s0m6Ag3izGufeOjDNiixrDqOTgLALZ8EdVVzT9lHbMAIMSszfnaTlIsdUk+3LRf l7HoufGCsGb0GDFg7qFWCjFIkqR6zSUEuw8aSgpWCdeum93pP1zJRqYNHsHSAA8LJq6W tQtg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@arista.com header.s=google header.b="LD4MRU/D"; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=arista.com Received: from out1.vger.email (out1.vger.email. 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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 v6 4/5] net/tcp: Do cleanup on tcp_md5_key_copy() failure Date: Wed, 23 Nov 2022 17:38:58 +0000 Message-Id: <20221123173859.473629-5-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123173859.473629-1-dima@arista.com> References: <20221123173859.473629-1-dima@arista.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1750309792257454105?= X-GMAIL-MSGID: =?utf-8?q?1750309792257454105?= 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 Acked-by: Jakub Kicinski Reviewed-by: Eric Dumazet --- 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 2ae6a061f36e..e214098087fe 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1630,13 +1630,8 @@ 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 83304d6a6bd0..21486b4a9774 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 Wed Nov 23 17:38:59 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 25098 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:f944:0:0:0:0:0 with SMTP id q4csp2930859wrr; Wed, 23 Nov 2022 09:45:04 -0800 (PST) X-Google-Smtp-Source: AA0mqf5HOP9s9kpizRKOtPqTqXz2A/MNUgve7JQR+nP4wxMTjvaRK8Eaj21kwcpgFzpKdv77qJxs X-Received: by 2002:a17:907:3907:b0:7ae:37a8:9b5c with SMTP id so7-20020a170907390700b007ae37a89b5cmr9328849ejc.241.1669225504071; Wed, 23 Nov 2022 09:45:04 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1669225504; cv=none; d=google.com; s=arc-20160816; b=LwfNiYPKFgQsyKoIDHS62dNCMQvFWBmDeQMP34MhRpB1qBxmvhuf1jrj4SjI2TCRBQ pM4refFm7svIoEamFIEciCUfAg8Cf4uBmJsI0wK+dVilkegB2oRUGYiD1LG6qcD2JwHP c13qOcdFxwIrv2rt5i3YwTw2dzBh0Bzs1dNt4W8N8hEkC3TbJna7T8V2nNPLfsz5AgUQ YNoyz1beCTRcbbZO/VmVnWI7LRfakJN5HjEGGn4nZfYJgRQg1B4bZYaOXdKZ2uIMD+Fl GBuucqgy5bDUGYvE0x+BJdODuY6vViEaJdE24bLOUfparV0sYqn9li0wd3f8wfxpOrHd RKCw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=B6YByZGXcPaxVAwfhLuLTeQPsdnWRNfeeMbhOwZgWvo=; b=tiQc3k7eRD7k6EU7unN+EbNOal7UjvvUd91tFFsf6i569Q+ZYFurIV5FsR1aD+3qS3 9Yet/LVtNxms0NyZStilJdVHAoVk9ZGLZHwiddyKgADQudBjnITMqnnRf/jDjpF67TL1 5sf957RXc1QjZX9ZnHupfndzsW+gwnzBPeT/KXcKgoAL/UVo8SBWu2qNbQHuTj6Svq6g f6qiJbK4xnWSiVEAlZ1ZxWM+jXTkyYEPwtiI1TJuNEIH8T59oDJn5XkjArV4dzzBsfl8 rptye/6+5QWzZTGyFPSDv7J/862lo1K5kXjhV3nXuKY0Om/2ubEVu4UuPr7QFzXmweCp Hbiw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@arista.com header.s=google header.b=JPBm03qP; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=arista.com Received: from out1.vger.email (out1.vger.email. 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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 v6 5/5] net/tcp: Separate initialization of twsk Date: Wed, 23 Nov 2022 17:38:59 +0000 Message-Id: <20221123173859.473629-6-dima@arista.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123173859.473629-1-dima@arista.com> References: <20221123173859.473629-1-dima@arista.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1750309802318050448?= X-GMAIL-MSGID: =?utf-8?q?1750309802318050448?= Convert BUG_ON() to WARN_ON_ONCE() and warn as well for unlikely static key int overflow error-path. Signed-off-by: Dmitry Safonov Acked-by: Jakub Kicinski Reviewed-by: Eric Dumazet --- 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 6908812d50d3..e002f2e1d4f2 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_disabled(&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_disabled(&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)