From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-118.freemail.mail.aliyun.com (out30-118.freemail.mail.aliyun.com [115.124.30.118]) (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 9CFFD746E; Wed, 14 Aug 2024 06:00:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.118 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723615241; cv=none; b=NCFMgAOZF4TDb49n/f8Sj2mdyLZ1KGgHHpUpkJyc1faHPD6mbDPzno/rxFBnejs/BemsPKBytJMyLo9VkMnP/Ux68rFitdw7LkOCV955aeHYGh1SmIWWkzp7M5xGyyDAesNrdmgrG+xtbGzXcYZR15atBQmT6udndpyEruYuUc0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723615241; c=relaxed/simple; bh=FOPl2havV4Ul4eVn3v9RX0fnwuQx/e7cxI411HDaxDw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=o+vA6NQnox3UwXsAoeQCaxf37IF0k4D9Gca0CjLiQb2GPmf+k/RS0BVCr1LJ38gdit8i7Ib+kf1cljvCOCUmIAR4ZjD8N7fF+pU4n6VyTug5p1NuckAXpGy+6Z/iNvn/mZlXIdnX5NQOio9RBTCIcvb4OViXxl33J4uXijuJeKQ= 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=OfrGxKJ9; arc=none smtp.client-ip=115.124.30.118 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="OfrGxKJ9" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1723615235; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=kuNwCNNAn1z+ogm4NogyBe1/xX19uPpstxB17dEWlzk=; b=OfrGxKJ9bkKD5J4cpTDhO8JiTscAPTFHmxb4906vM4meL1n65q92stvIqrOBXn8HodlFHtYPgtlYvAN7DSk7u5qPA1BMJld+YC7MpcQodeBxCTRlqd2GNSHl/z+7oS+eutIk1yh2K2UtUKfW2bDYvNLi0A+P/s8C/NZr0GLj9Oc= Received: from 30.221.148.210(mailfrom:alibuda@linux.alibaba.com fp:SMTPD_---0WCr9oFT_1723615233) by smtp.aliyun-inc.com; Wed, 14 Aug 2024 14:00:34 +0800 Message-ID: <4eeb32b7-d750-4c39-87df-43fd8365f163@linux.alibaba.com> Date: Wed, 14 Aug 2024 14:00:32 +0800 Precedence: bulk X-Mailing-List: linux-s390@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: davem@davemloft.net, dust.li@linux.alibaba.com, edumazet@google.com, gbayer@linux.ibm.com, guwen@linux.alibaba.com, jaka@linux.ibm.com, kuba@kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, syzbot+f69bfae0a4eb29976e44@syzkaller.appspotmail.com, tonylu@linux.alibaba.com, wenjia@linux.ibm.com References: <56255393-cae8-4cdf-9c91-b8ddf0bd2de2@linux.alibaba.com> <20240814035812.220388-1-aha310510@gmail.com> Content-Language: en-US From: "D. Wythe" In-Reply-To: <20240814035812.220388-1-aha310510@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 8/14/24 11:58 AM, Jeongjun Park wrote: > Because clcsk_*, like clcsock, is initialized during the smc init process, > the code was moved to prevent clcsk_* from having an address like > inet_sk(sk)->pinet6, thereby preventing the previously initialized values > ​​from being tampered with. I don't agree with your approach, but I finally got the problem you described. In fact, the issue here is that smc_sock should also be an inet_sock, whereas currently it's just a sock. Therefore, the best solution would be to embed an inet_sock within smc_sock rather than performing this movement as you suggested. struct smc_sock {               /* smc sock container */     union {         struct sock         sk;         struct inet_sock    inet;     };     ... Thanks. D. Wythe > > Additionally, if you don't need alignment in smc_inet6_prot , I'll modify > the patch to only add the necessary code without alignment. > > Regards, > Jeongjun Park >> >>> 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 = { >>>>>> --