1151310 - snmptrap can't create (or write to) /var/lib/net-snmp/snmpapp.conf if isn't run under root
Backported from:

commit 53ee5f1d240ac90adae935538bdc2ca13a8caa32
Author: Jan Safranek <jsafranek@users.sourceforge.net>
Date:   Wed Feb 18 16:29:16 2015 +0100

    CHANGES: snmplib: Fixed reporting 'error writing to /var/xxx/snmpapp.conf'.
    
    When a client utility, such as snmptrap, tries to write to its persistent
    configuration file (/var/net-snmp/snmpapp.conf in Fedora), do not report
    any error when open() fails. The tool is typically run by non-root, who
    cannot write to /var and the error just confuses users.
    
    And when doing it, make sure that "snmpapp" string is defined only on one
    place, just in case.

diff -up net-snmp-5.7.2/agent/mibgroup/disman/expression/expValueTable.c.test net-snmp-5.7.2/agent/mibgroup/disman/expression/expValueTable.c
--- net-snmp-5.7.2/agent/mibgroup/disman/expression/expValueTable.c.test	2012-10-10 00:28:58.000000000 +0200
+++ net-snmp-5.7.2/agent/mibgroup/disman/expression/expValueTable.c	2015-06-18 14:06:47.871027563 +0200
@@ -127,7 +127,7 @@ init_expValueTable(void)
     REGISTER_MIB("expValueTable",
                  expValueTable_variables, variable2,
                  expValueTable_variables_oid);
-    init_snmp("snmpapp");
+    init_snmp(NETSNMP_APPLICATION_CONFIG_TYPE);
 
     /*
      * Initialize a "session" that defines who we're going to talk to
diff -up net-snmp-5.7.2/apps/snmptranslate.c.test net-snmp-5.7.2/apps/snmptranslate.c
--- net-snmp-5.7.2/apps/snmptranslate.c.test	2012-10-10 00:28:58.000000000 +0200
+++ net-snmp-5.7.2/apps/snmptranslate.c	2015-06-18 14:06:47.872027568 +0200
@@ -236,7 +236,7 @@ main(int argc, char *argv[])
         }
     }
 
-    init_snmp("snmpapp");
+    init_snmp(NETSNMP_APPLICATION_CONFIG_TYPE);
     if (optind < argc)
         current_name = argv[optind];
 
diff -up net-snmp-5.7.2/apps/snmptrap.c.test net-snmp-5.7.2/apps/snmptrap.c
--- net-snmp-5.7.2/apps/snmptrap.c.test	2012-10-10 00:28:58.000000000 +0200
+++ net-snmp-5.7.2/apps/snmptrap.c	2015-06-18 14:06:47.872027568 +0200
@@ -386,7 +386,7 @@ main(int argc, char *argv[])
         snmp_free_pdu(response);
 
     snmp_close(ss);
-    snmp_shutdown("snmpapp");
+    snmp_shutdown(NETSNMP_APPLICATION_CONFIG_TYPE);
     SOCK_CLEANUP;
     return exitval;
 }
diff -up net-snmp-5.7.2/include/net-snmp/library/read_config.h.test net-snmp-5.7.2/include/net-snmp/library/read_config.h
--- net-snmp-5.7.2/include/net-snmp/library/read_config.h.test	2012-10-10 00:28:58.000000000 +0200
+++ net-snmp-5.7.2/include/net-snmp/library/read_config.h	2015-06-18 14:06:47.873027572 +0200
@@ -15,6 +15,12 @@ extern          "C" {
 #define PREMIB_CONFIG 1
 #define EITHER_CONFIG 2
 
+/*
+ * Value of 'type' parameter of various snmp_config calls,
+ * used by Net-SNMP client utilities.
+ */
+#define NETSNMP_APPLICATION_CONFIG_TYPE "snmpapp"
+
 #include <net-snmp/config_api.h>
 
     /*
diff -up net-snmp-5.7.2/snmplib/read_config.c.test net-snmp-5.7.2/snmplib/read_config.c
--- net-snmp-5.7.2/snmplib/read_config.c.test	2012-10-10 00:28:58.000000000 +0200
+++ net-snmp-5.7.2/snmplib/read_config.c	2015-06-18 14:06:47.874027577 +0200
@@ -1540,7 +1540,14 @@ read_config_store(const char *type, cons
         DEBUGMSGTL(("read_config:store", "storing: %s\n", line));
         fclose(fout);
     } else {
-        snmp_log(LOG_ERR, "read_config_store open failure on %s\n", filep);
+        if (strcmp(NETSNMP_APPLICATION_CONFIG_TYPE, type) != 0) {
+            /*
+             * Ignore this error in client utilities, they can run with random
+             * UID/GID and typically cannot write to /var. Error message just
+             * confuses people.
+             */
+            snmp_log(LOG_ERR, "read_config_store open failure on %s");
+        }
     }
 #ifdef NETSNMP_PERSISTENT_MASK
     umask(oldmask);
diff -up net-snmp-5.7.2/snmplib/snmp_parse_args.c.test net-snmp-5.7.2/snmplib/snmp_parse_args.c
--- net-snmp-5.7.2/snmplib/snmp_parse_args.c.test	2012-10-10 00:28:58.000000000 +0200
+++ net-snmp-5.7.2/snmplib/snmp_parse_args.c	2015-06-18 14:06:47.874027577 +0200
@@ -250,7 +250,7 @@ netsnmp_parse_args(int argc,
             break;
 
         case 'H':
-            init_snmp("snmpapp");
+            init_snmp(NETSNMP_APPLICATION_CONFIG_TYPE);
             fprintf(stderr, "Configuration directives understood:\n");
             read_config_print_usage("  ");
             return (NETSNMP_PARSE_ARGS_SUCCESS_EXIT);
@@ -640,7 +640,7 @@ netsnmp_parse_args(int argc,
     /*
      * read in MIB database and initialize the snmp library
      */
-    init_snmp("snmpapp");
+    init_snmp(NETSNMP_APPLICATION_CONFIG_TYPE);
 
     /*
      * session default version 
commit 653da2f955f88d7419363e6d31f2b5f0ffdc4f73
Author: Jan Safranek <jsafranek@users.sourceforge.net>
Date:   Thu Feb 19 13:40:37 2015 +0100

    Fixed missing printf argument from previous commit.

diff --git a/snmplib/read_config.c b/snmplib/read_config.c
index 6157fc6..2972232 100644
--- a/snmplib/read_config.c
+++ b/snmplib/read_config.c
@@ -1317,7 +1317,7 @@ read_config_store(const char *type, const char *line)
              * UID/GID and typically cannot write to /var. Error message just
              * confuses people.
              */
-            snmp_log(LOG_ERR, "read_config_store open failure on %s");
+            snmp_log(LOG_ERR, "read_config_store open failure on %s\n", filep);
         }
     }
 #ifdef NETSNMP_PERSISTENT_MASK