From patchwork Wed Jun 7 18:53:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rishabh Bhatnagar X-Patchwork-Id: 13271149 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 17997C7EE43 for ; Wed, 7 Jun 2023 18:54:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232650AbjFGSyE (ORCPT ); Wed, 7 Jun 2023 14:54:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60504 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233041AbjFGSyB (ORCPT ); Wed, 7 Jun 2023 14:54:01 -0400 Received: from smtp-fw-9103.amazon.com (smtp-fw-9103.amazon.com [207.171.188.200]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D04F31BD6; Wed, 7 Jun 2023 11:54:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1686164040; x=1717700040; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=QQccf1KeyTZf6ZPMjV/HwnVR62uBW11Zlzl2mRiQIRQ=; b=jpy35Re/yLIbl7HDAU7wscKlGkE1bdjlUv8Y3WpC8q0RI5mBI+wXcKtb 3dbDLBuSCWNu4r7uAsxdP7ygCZOu4BfL3LNyq5N6koDpiiF4W1kJk5qxc M7wTJnQgazMmIlIMkJTB/pgR6AWTsAJOmE37Ou3jJf9hbZKcbKaDUxrwA Y=; X-IronPort-AV: E=Sophos;i="6.00,224,1681171200"; d="scan'208";a="1136280854" Received: from pdx4-co-svc-p1-lb2-vlan3.amazon.com (HELO email-inbound-relay-pdx-2c-m6i4x-e7094f15.us-west-2.amazon.com) ([10.25.36.214]) by smtp-border-fw-9103.sea19.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Jun 2023 18:54:00 +0000 Received: from EX19MTAUWC002.ant.amazon.com (pdx1-ws-svc-p6-lb9-vlan2.pdx.amazon.com [10.236.137.194]) by email-inbound-relay-pdx-2c-m6i4x-e7094f15.us-west-2.amazon.com (Postfix) with ESMTPS id 31AA0413FA; Wed, 7 Jun 2023 18:54:00 +0000 (UTC) Received: from EX19D002UWC001.ant.amazon.com (10.13.138.148) by EX19MTAUWC002.ant.amazon.com (10.250.64.143) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.26; Wed, 7 Jun 2023 18:53:50 +0000 Received: from EX19MTAUEB001.ant.amazon.com (10.252.135.35) by EX19D002UWC001.ant.amazon.com (10.13.138.148) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.26; Wed, 7 Jun 2023 18:53:50 +0000 Received: from dev-dsk-risbhat-2b-8bdc64cd.us-west-2.amazon.com (10.189.73.169) by mail-relay.amazon.com (10.252.135.35) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Wed, 7 Jun 2023 18:53:50 +0000 Received: by dev-dsk-risbhat-2b-8bdc64cd.us-west-2.amazon.com (Postfix, from userid 22673075) id BF818222F; Wed, 7 Jun 2023 18:53:49 +0000 (UTC) From: Rishabh Bhatnagar To: CC: , , , , "Rishabh Bhatnagar" Subject: [PATCH 5.4 0/2] Backport few dfs related fixes to cifs Date: Wed, 7 Jun 2023 18:53:11 +0000 Message-ID: <20230607185313.11363-1-risbhat@amazon.com> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Recently we have been seeing kernel panic in cifs_reconnect function while accessing tgt_list. Looks like tgt_list is not initialized correctly. There are fixes already present in 5.10 and later trees. Backporting them to 5.4 CIFS VFS: \\172.30.1.14 cifs_reconnect: no target servers for DFS failover BUG: unable to handle page fault for address: fffffffffffffff8 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 260e067 P4D 260e067 PUD 2610067 PMD 0 Oops: 0000 [#1] SMP PTI RIP: 0010:cifs_reconnect+0x51d/0xef0 [cifs] RSP: 0018:ffffc90000693da0 EFLAGS: 00010282 RAX: fffffffffffffff8 RBX: ffff8887fa63b800 RCX: fffffffffffffff8 Call Trace: cifs_handle_standard+0x18d/0x1b0 [cifs] cifs_demultiplex_thread+0xa5c/0xc90 [cifs] kthread+0x113/0x130 *** BLURB HERE *** Paulo Alcantara (2): cifs: get rid of unused parameter in reconn_setup_dfs_targets() cifs: handle empty list of targets in cifs_reconnect() fs/cifs/connect.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-)