From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-99.freemail.mail.aliyun.com (out30-99.freemail.mail.aliyun.com [115.124.30.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1F5CA33FE; Wed, 14 Aug 2024 02:25:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.99 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723602340; cv=none; b=XO9T5ZbZYw2pH42SzbYcBEOhw7bJpEvyWnNxmJhb68UOJYB6C2qQNxbaK6cIX2zAEuiqOMRlLoYgxcLa/25HXQMnZ/Q9X2Cty7DomL1X7BQWeZGLj9JdMkSls9wwek4anqwMc2H1vVDvY2kgtffSo7Sb+n5rFaossovWr5o+toM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723602340; c=relaxed/simple; bh=sx4e2OSQ4+9w9uZQjuGm9Fj5GtIQiC0v8fBDiSanHbg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=i7qQHkjVMq6sEEsgglRE2jLIh1fCBVJQT6QZQ/uiSJf/i8/n6qv2SJ+OUFdQ9qXiW8JS5wiKJ7F5rqGGL1QsQxqema814VK+Qupg54HRse6z5pWQpoJlPXPyaG3oUyjy7yOGuGfin6Spkung66XqBgaIKv7Ao+8xf7lcUM78D3A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=W3YuOef+; arc=none smtp.client-ip=115.124.30.99 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="W3YuOef+" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1723602329; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=y07qmhnvEaJYsXCANnWzIUV9fhwW9kyK+2s4Kwdt/8o=; b=W3YuOef+Xu7n45seE03t6wSlmMVGjWwr49XUMjnHqBBv91FSSwEdYdrBRXbnasbUWoFGbIyTQkq2DqJm8NJDp7GAH9cO1nbECsNgojLg/KMTkdGqfXt6/LJUVpmSE+EHZdmkzDLCvUCvSBIAndE//xa+GCtX5QzunxDg/DXb4G0= Received: from 30.221.148.210(mailfrom:alibuda@linux.alibaba.com fp:SMTPD_---0WCqbUxf_1723602327) by smtp.aliyun-inc.com; Wed, 14 Aug 2024 10:25:28 +0800 Message-ID: <97b85c74-55e9-4607-8f30-3a938638a309@linux.alibaba.com> Date: Wed, 14 Aug 2024 10:25:27 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net,v3] net/smc: prevent NULL pointer dereference in txopt_get To: Jeongjun Park Cc: wenjia@linux.ibm.com, jaka@linux.ibm.com, gbayer@linux.ibm.com, tonylu@linux.alibaba.com, guwen@linux.alibaba.com, davem@davemloft.net, dust.li@linux.alibaba.com, edumazet@google.com, pabeni@redhat.com, kuba@kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, netdev@vger.kernel.org, syzbot+f69bfae0a4eb29976e44@syzkaller.appspotmail.com References: <20240813100722.181250-1-aha310510@gmail.com> Content-Language: en-US From: "D. Wythe" In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 8/13/24 7:48 PM, Jeongjun Park wrote: > D. Wythe wrote: >> >> >> On 8/13/24 6:07 PM, Jeongjun Park wrote: >>> Since smc_inet6_prot does not initialize ipv6_pinfo_offset, inet6_create() >>> copies an incorrect address value, sk + 0 (offset), to inet_sk(sk)->pinet6. >>> >>> In addition, since inet_sk(sk)->pinet6 and smc_sk(sk)->clcsock practically >>> point to the same address, when smc_create_clcsk() stores the newly >>> created clcsock in smc_sk(sk)->clcsock, inet_sk(sk)->pinet6 is corrupted >>> into clcsock. This causes NULL pointer dereference and various other >>> memory corruptions. >>> >>> To solve this, we need to add a smc6_sock structure for ipv6_pinfo_offset >>> initialization and modify the smc_sock structure. >>> >>> Reported-by: syzbot+f69bfae0a4eb29976e44@syzkaller.appspotmail.com >>> Tested-by: syzbot+f69bfae0a4eb29976e44@syzkaller.appspotmail.com >>> Fixes: d25a92ccae6b ("net/smc: Introduce IPPROTO_SMC") >>> Signed-off-by: Jeongjun Park >>> --- >>> net/smc/smc.h | 19 ++++++++++--------- >>> net/smc/smc_inet.c | 24 +++++++++++++++--------- >>> 2 files changed, 25 insertions(+), 18 deletions(-) >>> >>> diff --git a/net/smc/smc.h b/net/smc/smc.h >>> index 34b781e463c4..f4d9338b5ed5 100644 >>> --- a/net/smc/smc.h >>> +++ b/net/smc/smc.h >>> @@ -284,15 +284,6 @@ struct smc_connection { >>> >>> struct smc_sock { /* smc sock container */ >>> struct sock sk; >>> - struct socket *clcsock; /* internal tcp socket */ >>> - void (*clcsk_state_change)(struct sock *sk); >>> - /* original stat_change fct. */ >>> - void (*clcsk_data_ready)(struct sock *sk); >>> - /* original data_ready fct. */ >>> - void (*clcsk_write_space)(struct sock *sk); >>> - /* original write_space fct. */ >>> - void (*clcsk_error_report)(struct sock *sk); >>> - /* original error_report fct. */ >>> struct smc_connection conn; /* smc connection */ >>> struct smc_sock *listen_smc; /* listen parent */ >>> struct work_struct connect_work; /* handle non-blocking connect*/ >>> @@ -325,6 +316,16 @@ struct smc_sock { /* smc sock container */ >>> /* protects clcsock of a listen >>> * socket >>> * */ >>> + struct socket *clcsock; /* internal tcp socket */ >>> + void (*clcsk_state_change)(struct sock *sk); >>> + /* original stat_change fct. */ >>> + void (*clcsk_data_ready)(struct sock *sk); >>> + /* original data_ready fct. */ >>> + void (*clcsk_write_space)(struct sock *sk); >>> + /* original write_space fct. */ >>> + void (*clcsk_error_report)(struct sock *sk); >>> + /* original error_report fct. */ >>> + >>> }; >>> >>> #define smc_sk(ptr) container_of_const(ptr, struct smc_sock, sk) >>> diff --git a/net/smc/smc_inet.c b/net/smc/smc_inet.c >>> index bece346dd8e9..25f34fd65e8d 100644 >>> --- a/net/smc/smc_inet.c >>> +++ b/net/smc/smc_inet.c >>> @@ -60,16 +60,22 @@ static struct inet_protosw smc_inet_protosw = { >>> }; >>> >>> #if IS_ENABLED(CONFIG_IPV6) >>> +struct smc6_sock { >>> + struct smc_sock smc; >>> + struct ipv6_pinfo np; >>> +}; >> I prefer to: >> >> struct ipv6_pinfo inet6; > Okay, I'll write a v4 patch and send it to you tomorrow. > > Regards, > Jeongjun Park Before you issue the v4, I still don't know why you move clcsk_xxx from smc_connection to smc_sock, can you explain it ? Also, regarding alignment, it's okay for me whether it's aligned or not，But I checked the styles of other types of structures and did not strictly require alignment, so I now feel that there is no need to modify so much to do alignment. D. Wythe > >>> + >>> static struct proto smc_inet6_prot = { >>> - .name = "INET6_SMC", >>> - .owner = THIS_MODULE, >>> - .init = smc_inet_init_sock, >>> - .hash = smc_hash_sk, >>> - .unhash = smc_unhash_sk, >>> - .release_cb = smc_release_cb, >>> - .obj_size = sizeof(struct smc_sock), >>> - .h.smc_hash = &smc_v6_hashinfo, >>> - .slab_flags = SLAB_TYPESAFE_BY_RCU, >>> + .name = "INET6_SMC", >>> + .owner = THIS_MODULE, >>> + .init = smc_inet_init_sock, >>> + .hash = smc_hash_sk, >>> + .unhash = smc_unhash_sk, >>> + .release_cb = smc_release_cb, >>> + .obj_size = sizeof(struct smc6_sock), >>> + .h.smc_hash = &smc_v6_hashinfo, >>> + .slab_flags = SLAB_TYPESAFE_BY_RCU, >>> + .ipv6_pinfo_offset = offsetof(struct smc6_sock, np), >>> }; >>> >>> static const struct proto_ops smc_inet6_stream_ops = { >>> --