From: Ralph Boehme <slow@samba.org>
Date: Tue, 7 Mar 2017 14:03:12 +0000 (+0100)
Subject: s3/smbd: add and use retry_open() instead of defer_open() in two places
X-Git-Tag: samba-4.4.11~10
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=621abab71fd9457bc6586b7e7111e465cdbbe369;p=thirdparty%2Fsamba.git

s3/smbd: add and use retry_open() instead of defer_open() in two places

Add a new function that does an immediate open rescheduling.

The first deferred open this commit changes was never scheduled, as the
scheduling relies on a timeout of the watch on the sharemode lock.

This has been broken since the commits in

$ git log --reverse -p -10 8283fd0e0090ed12b0b12d5acb550642d621b026

That patchset added the dbwrap watch record logic to defer_open() and
removed the timers.

I'm doing this mainly to untangle the defer_open() logic which is
complicated by the lck arg.

Bug: https://bugzilla.samba.org/show_bug.cgi?id=7537

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
(cherry picked from commit beaba6222848fb4ff4392b2247c5be1094b1d65b)
---

diff --git a/source3/smbd/open.c b/source3/smbd/open.c
index 070e2286d3e..9ffae48963d 100644
--- a/source3/smbd/open.c
+++ b/source3/smbd/open.c
@@ -2037,6 +2037,40 @@ static void defer_open_done(struct tevent_req *req)
 	TALLOC_FREE(state);
 }
 
+/**
+ * Reschedule an open for immediate execution
+ **/
+static void retry_open(struct timeval request_time,
+		       struct smb_request *req,
+		       struct file_id id)
+{
+	struct deferred_open_record *open_rec = NULL;
+	bool ok;
+
+	DBG_DEBUG("request time [%s] mid [%" PRIu64 "] file_id [%s]\n",
+		  timeval_string(talloc_tos(), &request_time, false),
+		  req->mid,
+		  file_id_string_tos(&id));
+
+	open_rec = deferred_open_record_create(false, false, id);
+	if (open_rec == NULL) {
+		exit_server("talloc failed");
+	}
+
+	ok = push_deferred_open_message_smb(req,
+					    request_time,
+					    timeval_set(0, 0),
+					    id,
+					    open_rec);
+	if (!ok) {
+		exit_server("push_deferred_open_message_smb failed");
+	}
+
+	ok = schedule_deferred_open_message_smb(req->xconn, req->mid);
+	if (!ok) {
+		exit_server("schedule_deferred_open_message_smb failed");
+	}
+}
 
 /****************************************************************************
  On overwrite open ensure that the attributes match.
@@ -2822,8 +2856,7 @@ static NTSTATUS open_file_ntcreate(connection_struct *conn,
 
 		lck = get_existing_share_mode_lock(talloc_tos(), fsp->file_id);
 		if (lck == NULL) {
-			defer_open(NULL, request_time, timeval_set(0, 0),
-				   req, false, false, fsp->file_id);
+			retry_open(request_time, req, fsp->file_id);
 			DEBUG(10, ("No share mode lock found after "
 				   "EWOULDBLOCK, retrying sync\n"));
 			return NT_STATUS_SHARING_VIOLATION;
@@ -2849,8 +2882,7 @@ static NTSTATUS open_file_ntcreate(connection_struct *conn,
 		 * No oplock from Samba around. Immediately retry with
 		 * a blocking open.
 		 */
-		defer_open(lck, request_time, timeval_set(0, 0), req,
-			   false, false, fsp->file_id);
+		retry_open(request_time, req, fsp->file_id);
 
 		TALLOC_FREE(lck);
 		DEBUG(10, ("No Samba oplock around after EWOULDBLOCK. "