CIFS: Fix credit calculations in compound mid callback
authorPavel Shilovsky <pshilov@microsoft.com>
Wed, 23 Jan 2019 00:50:21 +0000 (16:50 -0800)
committerSteve French <stfrench@microsoft.com>
Thu, 24 Jan 2019 20:52:06 +0000 (14:52 -0600)
The current code doesn't do proper accounting for credits
in SMB1 case: it adds one credit per response only if we get
a complete response while it needs to return it unconditionally.
Fix this and also include malformed responses for SMB2+ into
accounting for credits because such responses have Credit
Granted field, thus nothing prevents to get a proper credit
value from them.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
fs/cifs/smb2ops.c
fs/cifs/transport.c

index 73f9c6af406531ace78533e878a2159beb3852a2..153238fc4fa986ba542778a95d313493d717a1c0 100644 (file)
@@ -154,7 +154,11 @@ smb2_get_credits(struct mid_q_entry *mid)
 {
        struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)mid->resp_buf;
 
-       return le16_to_cpu(shdr->CreditRequest);
+       if (mid->mid_state == MID_RESPONSE_RECEIVED
+           || mid->mid_state == MID_RESPONSE_MALFORMED)
+               return le16_to_cpu(shdr->CreditRequest);
+
+       return 0;
 }
 
 static int
index 202e0e84efdd7dfa7dff0501c1e9d3861f986afd..53532bd3f50d3d66886cd2465f6cbb0fed498e06 100644 (file)
@@ -786,17 +786,8 @@ static void
 cifs_compound_callback(struct mid_q_entry *mid)
 {
        struct TCP_Server_Info *server = mid->server;
-       unsigned int optype = mid->optype;
-       unsigned int credits_received = 0;
 
-       if (mid->mid_state == MID_RESPONSE_RECEIVED) {
-               if (mid->resp_buf)
-                       credits_received = server->ops->get_credits(mid);
-               else
-                       cifs_dbg(FYI, "Bad state for cancelled MID\n");
-       }
-
-       add_credits(server, credits_received, optype);
+       add_credits(server, server->ops->get_credits(mid), mid->optype);
 }
 
 static void