From 7332f2a6217ee6925f83ef0e725013067ed316ba Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Fri, 3 Sep 2010 12:00:49 -0400 Subject: [PATCH] cifs: eliminate some more premature cifsd exits If the tcpStatus is still CifsNew, the main cifs_demultiplex_loop can break out prematurely in some cases. This is wrong as we will almost always have other structures with pointers to the TCP_Server_Info. If the main loop breaks under any other condition other than tcpStatus == CifsExiting, then it'll face a use-after-free situation. I don't see any reason to treat a CifsNew tcpStatus differently than CifsGood. I believe we'll still want to attempt to reconnect in either case. What should happen in those situations is that the MIDs get marked as MID_RETRY_NEEDED. This will make CIFSSMBNegotiate return -EAGAIN, and then the caller can retry the whole thing on a newly reconnected socket. If that fails again in the same way, the caller of cifs_get_smb_ses should tear down the TCP_Server_Info struct. Signed-off-by: Jeff Layton Signed-off-by: Steve French --- fs/cifs/connect.c | 41 ++++++++++++----------------------------- 1 file changed, 12 insertions(+), 29 deletions(-) diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 5f68b968faa7..5fde83f0c75e 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -416,14 +416,6 @@ incomplete_rcv: } else continue; } else if (length <= 0) { - if (server->tcpStatus == CifsNew) { - cFYI(1, "tcp session abend after SMBnegprot"); - /* some servers kill the TCP session rather than - returning an SMB negprot error, in which - case reconnecting here is not going to help, - and so simply return error to mount */ - break; - } cFYI(1, "Reconnect after unexpected peek error %d", length); cifs_reconnect(server); @@ -464,27 +456,18 @@ incomplete_rcv: an error on SMB negprot response */ cFYI(1, "Negative RFC1002 Session Response Error 0x%x)", pdu_length); - if (server->tcpStatus == CifsNew) { - /* if nack on negprot (rather than - ret of smb negprot error) reconnecting - not going to help, ret error to mount */ - break; - } else { - /* give server a second to - clean up before reconnect attempt */ - msleep(1000); - /* always try 445 first on reconnect - since we get NACK on some if we ever - connected to port 139 (the NACK is - since we do not begin with RFC1001 - session initialize frame) */ - server->addr.sockAddr.sin_port = - htons(CIFS_PORT); - cifs_reconnect(server); - csocket = server->ssocket; - wake_up(&server->response_q); - continue; - } + /* give server a second to clean up */ + msleep(1000); + /* always try 445 first on reconnect since we get NACK + * on some if we ever connected to port 139 (the NACK + * is since we do not begin with RFC1001 session + * initialize frame) + */ + server->addr.sockAddr.sin_port = htons(CIFS_PORT); + cifs_reconnect(server); + csocket = server->ssocket; + wake_up(&server->response_q); + continue; } else if (temp != (char) 0) { cERROR(1, "Unknown RFC 1002 frame"); cifs_dump_mem(" Received Data: ", (char *)smb_buffer, -- 2.20.1