Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753893AbdGYTxf (ORCPT ); Tue, 25 Jul 2017 15:53:35 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36132 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753776AbdGYTYc (ORCPT ); Tue, 25 Jul 2017 15:24:32 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pavel Shilovsky , Steve French Subject: [PATCH 4.12 101/196] CIFS: Reconnect expired SMB sessions Date: Tue, 25 Jul 2017 12:21:40 -0700 Message-Id: <20170725192051.415915523@linuxfoundation.org> X-Mailer: git-send-email 2.13.3 In-Reply-To: <20170725192046.422343510@linuxfoundation.org> References: <20170725192046.422343510@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4546 Lines: 137 4.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pavel Shilovsky commit 511c54a2f69195b28afb9dd119f03787b1625bb4 upstream. According to the MS-SMB2 spec (3.2.5.1.6) once the client receives STATUS_NETWORK_SESSION_EXPIRED error code from a server it should reconnect the current SMB session. Currently the client doesn't do that. This can result in subsequent client requests failing by the server. The patch adds an additional logic to the demultiplex thread to identify expired sessions and reconnect them. Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/cifs/cifsglob.h | 2 ++ fs/cifs/cifssmb.c | 7 +++++++ fs/cifs/connect.c | 7 +++++++ fs/cifs/smb2ops.c | 23 +++++++++++++++++++++++ 4 files changed, 39 insertions(+) --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -367,6 +367,8 @@ struct smb_version_operations { unsigned int (*calc_smb_size)(void *); /* check for STATUS_PENDING and process it in a positive case */ bool (*is_status_pending)(char *, struct TCP_Server_Info *, int); + /* check for STATUS_NETWORK_SESSION_EXPIRED */ + bool (*is_session_expired)(char *); /* send oplock break response */ int (*oplock_response)(struct cifs_tcon *, struct cifs_fid *, struct cifsInodeInfo *); --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -1460,6 +1460,13 @@ cifs_readv_receive(struct TCP_Server_Inf return length; server->total_read += length; + if (server->ops->is_session_expired && + server->ops->is_session_expired(buf)) { + cifs_reconnect(server); + wake_up(&server->response_q); + return -1; + } + if (server->ops->is_status_pending && server->ops->is_status_pending(buf, server, 0)) { cifs_discard_remaining_data(server); --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -812,6 +812,13 @@ cifs_handle_standard(struct TCP_Server_I cifs_dump_mem("Bad SMB: ", buf, min_t(unsigned int, server->total_read, 48)); + if (server->ops->is_session_expired && + server->ops->is_session_expired(buf)) { + cifs_reconnect(server); + wake_up(&server->response_q); + return -1; + } + if (server->ops->is_status_pending && server->ops->is_status_pending(buf, server, length)) return -1; --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -1036,6 +1036,18 @@ smb2_is_status_pending(char *buf, struct return true; } +static bool +smb2_is_session_expired(char *buf) +{ + struct smb2_sync_hdr *shdr = get_sync_hdr(buf); + + if (shdr->Status != STATUS_NETWORK_SESSION_EXPIRED) + return false; + + cifs_dbg(FYI, "Session expired\n"); + return true; +} + static int smb2_oplock_response(struct cifs_tcon *tcon, struct cifs_fid *fid, struct cifsInodeInfo *cinode) @@ -2058,6 +2070,13 @@ handle_read_data(struct TCP_Server_Info return -ENOTSUPP; } + if (server->ops->is_session_expired && + server->ops->is_session_expired(buf)) { + cifs_reconnect(server); + wake_up(&server->response_q); + return -1; + } + if (server->ops->is_status_pending && server->ops->is_status_pending(buf, server, 0)) return -1; @@ -2375,6 +2394,7 @@ struct smb_version_operations smb20_oper .close_dir = smb2_close_dir, .calc_smb_size = smb2_calc_size, .is_status_pending = smb2_is_status_pending, + .is_session_expired = smb2_is_session_expired, .oplock_response = smb2_oplock_response, .queryfs = smb2_queryfs, .mand_lock = smb2_mand_lock, @@ -2458,6 +2478,7 @@ struct smb_version_operations smb21_oper .close_dir = smb2_close_dir, .calc_smb_size = smb2_calc_size, .is_status_pending = smb2_is_status_pending, + .is_session_expired = smb2_is_session_expired, .oplock_response = smb2_oplock_response, .queryfs = smb2_queryfs, .mand_lock = smb2_mand_lock, @@ -2543,6 +2564,7 @@ struct smb_version_operations smb30_oper .close_dir = smb2_close_dir, .calc_smb_size = smb2_calc_size, .is_status_pending = smb2_is_status_pending, + .is_session_expired = smb2_is_session_expired, .oplock_response = smb2_oplock_response, .queryfs = smb2_queryfs, .mand_lock = smb2_mand_lock, @@ -2638,6 +2660,7 @@ struct smb_version_operations smb311_ope .close_dir = smb2_close_dir, .calc_smb_size = smb2_calc_size, .is_status_pending = smb2_is_status_pending, + .is_session_expired = smb2_is_session_expired, .oplock_response = smb2_oplock_response, .queryfs = smb2_queryfs, .mand_lock = smb2_mand_lock,