[snmp/agent] Simultaneous snmpa:backup/1,2 calls interfere

Simultaneous snmpa#backup">snmpa:backup/1,2 calls interfere.
The master agent did not check if a backup was already in
progress when a backup request was accepted

OTP-9884

2 files changed, 73 insertions, 9 deletions

diff --git a/lib/snmp/doc/src/notes.xml b/lib/snmp/doc/src/notes.xml
index 9082868e39..2b0feb6682 100644
--- a/lib/snmp/doc/src/notes.xml
+++ b/lib/snmp/doc/src/notes.xml
@@ -33,6 +33,64 @@
   </header>
 
   <section>
+    <title>SNMP Development Toolkit 4.17.4</title>
+
+    <p>Version 4.17.4 supports code replacement in runtime from/to
+      version 4.17.3, 4.17.2, 4.17.1, 4.17, 4.16.2, 4.16.1 and 4.16.</p>
+
+    <section>
+      <title>Improvements and new features</title>
+      <p>-</p>
+
+      <!--
+      <list type="bulleted">
+        <item>
+          <p>[agent] DoS attack using GET-BULK with large value of 
+	  MaxRepetitions.
+	  A preventive method has been implementing by simply 
+	  limit the number of varbinds that can be included in 
+	  a Get-BULK response message. This is specified by the 
+	  new config option, 
+	  <seealso marker="snmp_app#agent_gb_max_vbs">gb_max_vbs</seealso>. 
+	  </p>
+	  <p>Own Id: OTP-9700</p>
+        </item>
+
+      </list>
+      -->
+
+    </section>
+
+    <section>
+      <title>Reported Fixed Bugs and Malfunctions</title>
+      <!--
+      <p>-</p>
+      -->
+
+      <list type="bulleted">
+        <item>
+          <p>[agent] Simultaneous 
+	  <seealso marker="snmpa#backup">snmpa:backup/1,2</seealso> 
+	  calls can interfere.
+	  The master agent did not check if a backup was already in 
+	  progress when a backup request was accepted. </p>
+          <p>Own Id: OTP-9884</p>
+          <p>Aux Id: Seq 11995</p>
+        </item>
+
+      </list>
+
+    </section>
+
+    <section>
+      <title>Incompatibilities</title>
+      <p>-</p>
+    </section>
+
+  </section> <!-- 4.17.4 -->
+
+
+  <section>
     <title>SNMP Development Toolkit 4.17.3</title>
 
     <p>Version 4.17.3 supports code replacement in runtime from/to
diff --git a/lib/snmp/doc/src/snmpa.xml b/lib/snmp/doc/src/snmpa.xml
index 1be6abe6dd..3bc2063f4e 100644
--- a/lib/snmp/doc/src/snmpa.xml
+++ b/lib/snmp/doc/src/snmpa.xml
@@ -1,10 +1,10 @@
-<?xml version="1.0" encoding="latin1" ?>
+<?xml version="1.0" encoding="iso-8859-1" ?>
 <!DOCTYPE erlref SYSTEM "erlref.dtd">
 
 <erlref>
   <header>
     <copyright>
-      <year>2004</year><year>2010</year>
+      <year>2004</year><year>2012</year>
       <holder>Ericsson AB. All Rights Reserved.</holder>
     </copyright>
     <legalnotice>
@@ -198,12 +198,18 @@ notification_delivery_info() = #snmpa_notification_delivery_info{}
       <type>
         <v>BackupDir = string()</v>
         <v>Agent = pid() | atom()</v>
+        <v>Reason = backup_in_progress | term()</v>
       </type>
       <desc>
         <p>Backup persistent/permanent data handled by the agent
           (such as local-db, mib-data and vacm). </p>
         <p>Data stored by mnesia is not handled. </p>
         <p>BackupDir cannot be identical to DbDir. </p>
+        <p>Simultaneous backup calls are <em>not</em> allowed. 
+	That is, two different processes cannot simultaneously 
+	successfully call this function. One of them will be first, 
+	and succeed. The second will fail with the error reason
+	<c>backup_in_progress</c>. </p>
 
         <marker id="info"></marker>
       </desc>
@@ -217,13 +223,13 @@ notification_delivery_info() = #snmpa_notification_delivery_info{}
       </type>
       <desc>
         <p>Returns a list (a dictionary) containing information about
-          the agent. Information includes loaded MIBs, registered
-          sub-agents, some information about the memory allocation. </p>
-        <p>As of version 4.4 the format of the info has been changed. 
-          To convert the info to the old format, call the 
-          <seealso marker="#old_info_format">old_info_format</seealso> 
-          function. </p>
-
+	the agent. Information includes loaded MIBs, registered
+	sub-agents, some information about the memory allocation. </p>
+	<p>As of version 4.4 the format of the info has been changed. 
+	To convert the info to the old format, call the 
+	<seealso marker="#old_info_format">old_info_format</seealso> 
+	function. </p>
+	
         <marker id="old_info_format"></marker>
       </desc>
     </func>