[asterisk-commits] tilghman: branch 1.4 r182449 - /branches/1.4/main/db.c

[SVN commits to the Asterisk project]

Author: tilghman
Date: Tue Mar 17 00:50:52 2009
New Revision: 182449

URL: http://svn.digium.com/svn-view/asterisk?view=rev&rev=182449
Log:
Fix race in astdb
The underlying db1 implementation does not fully isolate the pages retrieved
from astdb, so the lock protecting accesses needs to be extended until the
copy from the shared memory structure is done.
(closes issue #14682)
 Reported by: makoto

Modified:
    branches/1.4/main/db.c

Modified: branches/1.4/main/db.c
URL: http://svn.digium.com/svn-view/asterisk/branches/1.4/main/db.c?view=diff&rev=182449&r1=182448&r2=182449
==============================================================================
--- branches/1.4/main/db.c (original)
+++ branches/1.4/main/db.c Tue Mar 17 00:50:52 2009
@@ -187,10 +187,8 @@
 	memset(value, 0, valuelen);
 	key.data = fullkey;
 	key.size = fullkeylen + 1;
-	
+
 	res = astdb->get(astdb, &key, &data, 0);
-	
-	ast_mutex_unlock(&dblock);
 
 	/* Be sure to NULL terminate our data either way */
 	if (res) {
@@ -208,6 +206,11 @@
 			ast_log(LOG_NOTICE, "Strange, empty value for /%s/%s\n", family, keys);
 		}
 	}
+
+	/* Data is not fully isolated for concurrency, so the lock must be extended
+	 * to after the copy to the output buffer. */
+	ast_mutex_unlock(&dblock);
+
 	return res;
 }