smb3: add credits we receive from oplock/break PDUs

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>

diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 6a9c47541c53d0983a068703106ddacdbc834e04..7b8b58fb4d3fbdcf898d306a585c7332cd2c0ef5 100644 (file)
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -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)