smbd: Fix raw.batch.exclusive[59]

The level we have to break to depend on the breakers create_disposition:
If we overwrite, we have to break to none.

This patch overloads the "op_type" field in the break message we send
across to the smbd holding the oplock with the oplock level we want to
break to. Because it depends on the create_disposition in the breaking
open, only the breaker can make that decision. We might want to use
a different mechanism for this in the future, but for now using the
op_type field seems acceptable to me.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>

2 files changed, 29 insertions, 10 deletions

diff --git a/source3/smbd/open.c b/source3/smbd/open.c
index a9147f80b8..494145397d 100644
--- a/source3/smbd/open.c
+++ b/source3/smbd/open.c
@@ -1168,7 +1168,8 @@ static NTSTATUS open_mode_check(connection_struct *conn,
  */
 
 static NTSTATUS send_break_message(struct messaging_context *msg_ctx,
-				   const struct share_mode_entry *exclusive)
+				   const struct share_mode_entry *exclusive,
+				   uint16_t break_to)
 {
 	NTSTATUS status;
 	char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
@@ -1179,6 +1180,9 @@ static NTSTATUS send_break_message(struct messaging_context *msg_ctx,
 	/* Create the message. */
 	share_mode_entry_to_message(msg, exclusive);
 
+	/* Overload entry->op_type */
+	SSVAL(msg,OP_BREAK_MSG_OP_TYPE_OFFSET, break_to);
+
 	status = messaging_send_buf(msg_ctx, exclusive->pid,
 				    MSG_SMB_BREAK_REQUEST,
 				    (uint8 *)msg, sizeof(msg));
@@ -1292,12 +1296,14 @@ static bool validate_oplock_types(struct share_mode_lock *lck)
 static bool delay_for_oplock(files_struct *fsp,
 			     int oplock_request,
 			     struct share_mode_lock *lck,
-			     bool have_sharing_violation)
+			     bool have_sharing_violation,
+			     uint32_t create_disposition)
 {
 	struct share_mode_data *d = lck->data;
 	struct share_mode_entry *entry;
 	uint32_t num_non_stat_opens = 0;
 	uint32_t i;
+	uint16_t break_to;
 
 	if ((oplock_request & INTERNAL_OPEN_ONLY) || is_stat_open(fsp->access_mask)) {
 		return false;
@@ -1342,11 +1348,21 @@ static bool delay_for_oplock(files_struct *fsp,
 		return false;
 	}
 
+	switch (create_disposition) {
+	case FILE_SUPERSEDE:
+	case FILE_OVERWRITE_IF:
+		break_to = NO_OPLOCK;
+		break;
+	default:
+		break_to = LEVEL_II_OPLOCK;
+		break;
+	}
+
 	if (have_sharing_violation && (entry->op_type & BATCH_OPLOCK)) {
 		if (share_mode_stale_pid(d, 0)) {
 			return false;
 		}
-		send_break_message(fsp->conn->sconn->msg_ctx, entry);
+		send_break_message(fsp->conn->sconn->msg_ctx, entry, break_to);
 		return true;
 	}
 	if (have_sharing_violation) {
@@ -1366,7 +1382,7 @@ static bool delay_for_oplock(files_struct *fsp,
 		return false;
 	}
 
-	send_break_message(fsp->conn->sconn->msg_ctx, entry);
+	send_break_message(fsp->conn->sconn->msg_ctx, entry, break_to);
 	return true;
 }
 
@@ -2343,7 +2359,7 @@ static NTSTATUS open_file_ntcreate(connection_struct *conn,
 			smb_panic("validate_oplock_types failed");
 		}
 
-		if (delay_for_oplock(fsp, 0, lck, false)) {
+		if (delay_for_oplock(fsp, 0, lck, false, create_disposition)) {
 			schedule_defer_open(lck, request_time, req);
 			TALLOC_FREE(lck);
 			DEBUG(10, ("Sent oplock break request to kernel "
@@ -2455,7 +2471,8 @@ static NTSTATUS open_file_ntcreate(connection_struct *conn,
 	if ((req != NULL) &&
 	    delay_for_oplock(
 		    fsp, oplock_request, lck,
-		    NT_STATUS_EQUAL(status, NT_STATUS_SHARING_VIOLATION))) {
+		    NT_STATUS_EQUAL(status, NT_STATUS_SHARING_VIOLATION),
+		    create_disposition)) {
 		schedule_defer_open(lck, request_time, req);
 		TALLOC_FREE(lck);
 		fd_close(fsp);
diff --git a/source3/smbd/oplock.c b/source3/smbd/oplock.c
index e2880c5de9..f1b89b4650 100644
--- a/source3/smbd/oplock.c
+++ b/source3/smbd/oplock.c
@@ -510,6 +510,7 @@ static void process_oplock_break_message(struct messaging_context *msg_ctx,
 		struct smbd_server_connection);
 	struct server_id self = messaging_server_id(sconn->msg_ctx);
 	struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
+	uint16_t break_to;
 
 	if (data->data == NULL) {
 		DEBUG(0, ("Got NULL buffer\n"));
@@ -523,9 +524,10 @@ static void process_oplock_break_message(struct messaging_context *msg_ctx,
 
 	/* De-linearize incoming message. */
 	message_to_share_mode_entry(&msg, (char *)data->data);
+	break_to = msg.op_type;
 
-	DEBUG(10, ("Got oplock break message from pid %s: %s/%llu\n",
-		   server_id_str(talloc_tos(), &src),
+	DEBUG(10, ("Got oplock break to %u message from pid %s: %s/%llu\n",
+		   (unsigned)break_to, server_id_str(talloc_tos(), &src),
 		   file_id_string_tos(&msg.id),
 		   (unsigned long long)msg.share_file_id));
 
@@ -545,8 +547,7 @@ static void process_oplock_break_message(struct messaging_context *msg_ctx,
 		return;
 	}
 
-	if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
-	    !EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
+	if (break_to == fsp->oplock_type) {
 		DEBUG(3, ("Already downgraded oplock on %s: %s\n",
 			  file_id_string_tos(&fsp->file_id),
 			  fsp_str_dbg(fsp)));
@@ -556,6 +557,7 @@ static void process_oplock_break_message(struct messaging_context *msg_ctx,
 	use_kernel = lp_kernel_oplocks(SNUM(fsp->conn)) && koplocks;
 
 	if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
+	    (break_to != NO_OPLOCK) &&
 	    !(use_kernel && !(koplocks->flags & KOPLOCKS_LEVEL2_SUPPORTED)) &&
 	    lp_level2_oplocks(SNUM(fsp->conn))) {
 		break_to_level2 = True;