From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A598C4361B for ; Wed, 12 May 2021 20:13:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 55E7A61408 for ; Wed, 12 May 2021 20:13:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1385059AbhELUGW (ORCPT ); Wed, 12 May 2021 16:06:22 -0400 Received: from so254-9.mailgun.net ([198.61.254.9]:42004 "EHLO so254-9.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244479AbhELSWz (ORCPT ); Wed, 12 May 2021 14:22:55 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1620843707; h=Message-ID: Subject: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=TQGGOgj3JUABFf8IznwP+ZQFY3QR/fd0Xw3f1wk9rtI=; b=V7CSIQnB6g7RhZ81iqfwdKbKToPvgx+3O+cNrMBVQlGpG6aCe6I5t8LKGz/uWZxqXhOURYxj Fi/ooKREJ0gdTJRdvsfUopx55Fk7IJn4t+eKwFK2aSxAQc97TXTXry6j8nIiCcE3Nuh/Qkz9 GZCTS1Twr9oUXcO5CyZS7+w27ik= X-Mailgun-Sending-Ip: 198.61.254.9 X-Mailgun-Sid: WyJiZjI2MiIsICJuZXRkZXZAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n02.prod.us-east-1.postgun.com with SMTP id 609c1cac5702f8d96992d7ed (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 12 May 2021 18:21:32 GMT Sender: kapandey=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 17258C43145; Wed, 12 May 2021 18:21:31 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: kapandey) by smtp.codeaurora.org (Postfix) with ESMTPSA id AA245C4338A; Wed, 12 May 2021 18:21:30 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 12 May 2021 23:51:30 +0530 From: kapandey@codeaurora.org To: willemb@google.com, pabeni@redhat.com, netdev@vger.kernel.org, eric.dumazet@gmail.com, sharathv@codeaurora.org, subashab@codeaurora.org Subject: Panic in udp4_lib_lookup2 Message-ID: X-Sender: kapandey@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi All, We observed panic in udp_lib_lookup with below call trace: [136523.743271] (7) Call trace: [136523.743275] (7) udp4_lib_lookup2+0x88/0x1d8 [136523.743277] (7) __udp4_lib_lookup+0x168/0x194 [136523.743280] (7) udp4_lib_lookup+0x28/0x54 [136523.743285] (7) nf_sk_lookup_slow_v4+0x2b4/0x384 [136523.743289] (7) owner_mt+0xb8/0x248 [136523.743292] (7) ipt_do_table+0x28c/0x6a8 [136523.743295] (7) iptable_filter_hook+0x24/0x30 [136523.743299] (7) nf_hook_slow+0xa8/0x148 [136523.743303] (7) ip_local_deliver+0xa8/0x14c [136523.743305] (7) ip_rcv+0xe0/0x134 We suspect this might happen due to below sequence: Time CPU X CPU Y t0 inet_release -> udp_lib_close -> sk_common_release -> udp_lib_unhash inet_diag_handler_cmd -> udp_diag_destroy -> __udp_diag_destroy -> udp_lib_rehash t1 if(sk hashed) if(sk hashed) sk_del_node_init_rcu hlist_del_init_rcu(udp_portaddr_node) t2 if(hslot2 != nhslot2) hlist_del_init_rcu(udp_portaddr_node) hlist_add_head_rcu(udp_portaddr_node) t3 sk is freed here After t3 any use of that added udp_portaddr_node will cause panic. Same happens in udp4_lib_lookup2/udp6_lib_lookup2. We dont have any reproducer for this, getting hit during random testing. Pls let us know how this be resolved. Thanks, KP