smb3: add credits we receive from oplock/break PDUs
authorRonnie Sahlberg <lsahlber@redhat.com>
Wed, 23 Jan 2019 06:20:38 +0000 (16:20 +1000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 31 Jan 2019 07:14:37 +0000 (08:14 +0100)
commit 2e5700bdde438ed708b36d8acd0398dc73cbf759 upstream.

Otherwise we gradually leak credits leading to potential
hung session.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/cifs/smb2misc.c

index 6a9c475..7b8b58f 100644 (file)
@@ -648,6 +648,13 @@ smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
        if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
                return false;
 
+       if (rsp->sync_hdr.CreditRequest) {
+               spin_lock(&server->req_lock);
+               server->credits += le16_to_cpu(rsp->sync_hdr.CreditRequest);
+               spin_unlock(&server->req_lock);
+               wake_up(&server->request_q);
+       }
+
        if (rsp->StructureSize !=
                                smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
                if (le16_to_cpu(rsp->StructureSize) == 44)