From: Stefan Metzmacher <metze@samba.org>
Date: Wed, 23 Dec 2020 10:59:05 +0000 (+0100)
Subject: share_mode_lock: DEBUG/ASSERT recursion deadlock detection
X-Git-Tag: tevent-0.11.0~2042
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=db743ab005bc7671d4fb0f5bea895c1097b707c5;p=thirdparty%2Fsamba.git

share_mode_lock: DEBUG/ASSERT recursion deadlock detection

This situation should never happen!

The known trigger is fixed with the change to adouble_open_rsrc_fsp()

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
---

diff --git a/source3/locking/share_mode_lock.c b/source3/locking/share_mode_lock.c
index 80c04fdeda0..e8bb3e58e1f 100644
--- a/source3/locking/share_mode_lock.c
+++ b/source3/locking/share_mode_lock.c
@@ -880,8 +880,15 @@ struct share_mode_lock *get_share_mode_lock(
 
 	if (static_share_mode_data != NULL) {
 		if (!file_id_equal(&static_share_mode_data->id, &id)) {
-			DEBUG(1, ("Can not lock two share modes "
-				  "simultaneously\n"));
+			struct file_id_buf existing;
+			struct file_id_buf requested;
+
+			DBG_ERR("Can not lock two share modes "
+				"simultaneously: existing %s requested %s\n",
+				file_id_str_buf(static_share_mode_data->id, &existing),
+				file_id_str_buf(id, &requested));
+
+			smb_panic(__location__);
 			goto fail;
 		}
 		goto done;
@@ -904,6 +911,7 @@ struct share_mode_lock *get_share_mode_lock(
 	cmp = tdb_data_cmp(share_mode_lock_key, key);
 	if (cmp != 0) {
 		DBG_WARNING("Can not lock two share modes simultaneously\n");
+		smb_panic(__location__);
 		goto fail;
 	}
 
@@ -929,6 +937,15 @@ done:
 
 	talloc_set_destructor(lck, share_mode_lock_destructor);
 
+	if (CHECK_DEBUGLVL(DBGLVL_DEBUG)) {
+		struct file_id_buf returned;
+
+		DBG_DEBUG("Returning %s (data_refcount=%zu key_refcount=%zu)\n",
+			  file_id_str_buf(id, &returned),
+			  static_share_mode_data_refcount,
+			  share_mode_lock_key_refcount);
+	}
+
 	return lck;
 fail:
 	TALLOC_FREE(lck);