Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752124AbdF1W5I (ORCPT ); Wed, 28 Jun 2017 18:57:08 -0400 Received: from a2nlsmtp01-05.prod.iad2.secureserver.net ([198.71.225.49]:59254 "EHLO a2nlsmtp01-05.prod.iad2.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751813AbdF1W5C (ORCPT ); Wed, 28 Jun 2017 18:57:02 -0400 x-originating-ip: 107.180.71.197 From: Long Li To: Steve French , linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org Cc: Long Li Subject: [PATCH v4] cifs: Do not modify mid entry after submitting I/O in cifs_call_async Date: Wed, 28 Jun 2017 15:55:55 -0700 Message-Id: <1498690555-8454-1-git-send-email-longli@exchange.microsoft.com> X-Mailer: git-send-email 1.7.1 X-CMAE-Envelope: MS4wfKlmV0aLPGqXPsylffRpH/DCU2QIn97+nVkolMqsGU2rpn/nhBY9vEbkV6Zf08YRYxkGXS0MYOPDD9r89zU+w5Kbb66aKcfhfiHLlkoVkBYrQZR9JQR+ efnUeJiZ58QxGfMHB8T1vBRuJvkAg6sQ7d0MKoEXmbv1iGJegpaTfsYNorcUkMYymoiENE5vLboLh0kBrQUAupiEMYHBrtRG5sWM8d9sXpNYt314yR1I6qPQ nNeOj0NjkJXHzW2KS6b+QGJG9jRkB0OJCVSW1O+VSc9j3z77mpFLAbbvHcd2T2zq4+vqseK04Mgz5k75WcdRkf8pQ1be+yiSL98rJGtZ60w= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1201 Lines: 38 From: Long Li In cifs_call_async, server may respond as soon as I/O is submitted. Because mid entry is freed on the return path, it should not be modified after I/O is submitted. cifs_save_when_sent modifies the sent timestamp in mid entry, and should not be called after I/O. Call it before I/O. Signed-off-by: Long Li Reviewed-by: Pavel Shilovsky --- fs/cifs/transport.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index 47a125e..7efbab0 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -536,11 +536,14 @@ cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst, list_add_tail(&mid->qhead, &server->pending_mid_q); spin_unlock(&GlobalMid_Lock); - + /* + * Need to store the time in mid before calling I/O. For call_async, + * I/O response may come back and free the mid entry on another thread. + */ + cifs_save_when_sent(mid); cifs_in_send_inc(server); rc = smb_send_rqst(server, rqst, flags); cifs_in_send_dec(server); - cifs_save_when_sent(mid); if (rc < 0) { server->sequence_number -= 2; -- 2.7.4