linux-kernel - [PATCH 3.12 13/58] CIFS: Fix SMB2+ interim response processing for read requests

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 16 Mar 2016 11:58:58 +0100
From:	Jiri Slaby <jslaby@...e.cz>
To:	stable@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org,
	Pavel Shilovsky <pshilovsky@...ba.org>,
	Steve French <smfrench@...il.com>, Jiri Slaby <jslaby@...e.cz>
Subject: [PATCH 3.12 13/58] CIFS: Fix SMB2+ interim response processing for read requests

From: Pavel Shilovsky <pshilovsky@...ba.org>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

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@...ba.org>
Tested-by: Shirish Pargaonkar <shirishpargaonkar@...il.com>
Signed-off-by: Steve French <smfrench@...il.com>
Signed-off-by: Jiri Slaby <jslaby@...e.cz>
---
 fs/cifs/cifssmb.c | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index ea938a8bf240..f53a6e8204d8 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1378,11 +1378,10 @@ 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;
@@ -1396,10 +1395,20 @@ cifs_readv_discard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 		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)
 {
@@ -1428,6 +1437,12 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 		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) {
-- 
2.7.3