Patch "CIFS: Fix SMB2+ interim response processing for read requests" has been added to the 4.4-stable tree

Patch "CIFS: Fix SMB2+ interim response processing for read requests" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    CIFS: Fix SMB2+ interim response processing for read requests

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     cifs-fix-smb2-interim-response-processing-for-read-requests.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 6cc3b24235929b54acd5ecc987ef11a425bd209e Mon Sep 17 00:00:00 2001
From: Pavel Shilovsky <pshilovsky@samba.org>
Date: Sat, 27 Feb 2016 11:58:18 +0300
Subject: CIFS: Fix SMB2+ interim response processing for read requests

From: Pavel Shilovsky <pshilovsky@samba.org>

commit 6cc3b24235929b54acd5ecc987ef11a425bd209e upstream.

For interim responses we only need to parse a header and update
a number credits. Now it is done for all SMB2+ command except
SMB2_READ which is wrong. Fix this by adding such processing.

Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Tested-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/cifs/cifssmb.c |   21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1396,11 +1396,10 @@ openRetry:
  * current bigbuf.
  */
 static int
-cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
+discard_remaining_data(struct TCP_Server_Info *server)
 {
 	unsigned int rfclen = get_rfc1002_length(server->smallbuf);
 	int remaining = rfclen + 4 - server->total_read;
-	struct cifs_readdata *rdata = mid->callback_data;
 
 	while (remaining > 0) {
 		int length;
@@ -1414,10 +1413,20 @@ cifs_readv_discard(struct TCP_Server_Inf
 		remaining -= length;
 	}
 
-	dequeue_mid(mid, rdata->result);
 	return 0;
 }
 
+static int
+cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
+{
+	int length;
+	struct cifs_readdata *rdata = mid->callback_data;
+
+	length = discard_remaining_data(server);
+	dequeue_mid(mid, rdata->result);
+	return length;
+}
+
 int
 cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 {
@@ -1446,6 +1455,12 @@ cifs_readv_receive(struct TCP_Server_Inf
 		return length;
 	server->total_read += length;
 
+	if (server->ops->is_status_pending &&
+	    server->ops->is_status_pending(buf, server, 0)) {
+		discard_remaining_data(server);
+		return -1;
+	}
+
 	/* Was the SMB read successful? */
 	rdata->result = server->ops->map_error(buf, false);
 	if (rdata->result != 0) {


Patches currently in stable-queue which might be from pshilovsky@samba.org are

queue-4.4/cifs-fix-smb2-interim-response-processing-for-read-requests.patch