[Samba] Re: 3.0.25a closing network drive connections?

[Jeremy Allison]

On Tue, Jun 12, 2007 at 02:14:12PM -0400, Josh Kelley wrote:
> On 6/11/07, Gerald (Jerry) Carter <jerry at samba.org> wrote:
> >> [2007/06/08 14:02:21, 10] lib/util_sock.c:read_data(525)
> >>  read_data: read of 4 returned 0. Error = Success
> >> [2007/06/08 14:02:21, 10] lib/util_sock.c:receive_smb_raw(672)
> >>  receive_smb_raw: length < 0!
> >> [2007/06/08 14:02:21, 3] smbd/process.c:timeout_processing(1328)
> >>  timeout_processing: End of file from client (client has disconnected).
> >>
> >> Is anyone else seeing similar problems?  Should I open a Bugzilla or
> >> post the full debug logs here?
> >
> >The client disconnected.  This is not smbd's fault.
> 
> Upon further investigation, I think that smbd may be sending invalid
> NOTIFY responses to the client, causing the client to disconnect.
> 
> I opened a Bugzilla with a level 10 debug log, Wireshark capture, and
> instructions to reproduce, since I thought that would be better than
> posting all of that stuff here:
> https://bugzilla.samba.org/show_bug.cgi?id=4689
> 
> I hope it's okay that I did so.  Thank you for your time.

Here's the patch for this I added for 3.0.25b. On testing
here it seems to do the correct thing with WindowsXP SP2.

Jeremy.
-------------- next part --------------
Index: smbd/nttrans.c
===================================================================
--- smbd/nttrans.c	(revision 23444)
+++ smbd/nttrans.c	(working copy)
@@ -1979,8 +1979,7 @@
 		 * here.
 		 */
 
-		change_notify_reply(inbuf, max_param_count,
-				    fsp->notify);
+		change_notify_reply(inbuf, fsp->notify);
 
 		/*
 		 * change_notify_reply() above has independently sent its
@@ -1993,8 +1992,7 @@
 	 * No changes pending, queue the request
 	 */
 
-	status = change_notify_add_request(inbuf, max_param_count, filter,
-					   recursive, fsp);
+	status = change_notify_add_request(inbuf, filter, recursive, fsp);
 	if (!NT_STATUS_IS_OK(status)) {
 		return ERROR_NT(status);
 	}
Index: smbd/notify.c
===================================================================
--- smbd/notify.c	(revision 23444)
+++ smbd/notify.c	(working copy)
@@ -27,7 +27,6 @@
 	struct files_struct *fsp;	/* backpointer for cancel by mid */
 	char request_buf[smb_size];
 	uint32 filter;
-	uint32 max_param_count;
 	uint32 current_bufsize;
 	struct notify_mid_map *mid_map;
 	void *backend_data;
@@ -126,12 +125,12 @@
 				    "failed.");
 }
 
-void change_notify_reply(const char *request_buf, uint32 max_param_count,
+void change_notify_reply(const char *request_buf,
 			 struct notify_change_buf *notify_buf)
 {
 	char *outbuf = NULL;
 	prs_struct ps;
-	size_t buflen = smb_size+38+max_param_count;
+	size_t buflen;
 
 	if (notify_buf->num_changes == -1) {
 		change_notify_reply_packet(request_buf, NT_STATUS_OK);
@@ -145,14 +144,7 @@
 		goto done;
 	}
 
-	if (prs_offset(&ps) > max_param_count) {
-		/*
-		 * We exceed what the client is willing to accept. Send
-		 * nothing.
-		 */
-		change_notify_reply_packet(request_buf, NT_STATUS_OK);
-		goto done;
-	}
+	buflen = smb_size+38+prs_offset(&ps) + 4 /* padding */;
 
 	if (!(outbuf = SMB_MALLOC_ARRAY(char, buflen))) {
 		change_notify_reply_packet(request_buf, NT_STATUS_NO_MEMORY);
@@ -214,7 +206,7 @@
 	return status;
 }
 
-NTSTATUS change_notify_add_request(const char *inbuf, uint32 max_param_count,
+NTSTATUS change_notify_add_request(const char *inbuf, 
 				   uint32 filter, BOOL recursive,
 				   struct files_struct *fsp)
 {
@@ -231,7 +223,6 @@
 	map->req = request;
 
 	memcpy(request->request_buf, inbuf, sizeof(request->request_buf));
-	request->max_param_count = max_param_count;
 	request->current_bufsize = 0;
 	request->filter = filter;
 	request->fsp = fsp;
@@ -408,7 +399,6 @@
 	 */
 
 	change_notify_reply(fsp->notify->requests->request_buf,
-			    fsp->notify->requests->max_param_count,
 			    fsp->notify);
 
 	change_notify_remove_request(fsp->notify->requests);