X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=src%2Fsnmp_agent.c;h=bb4a7e4271ed459aa31ced5a4b6ba4378a119a02;hb=39049b56158161b4f9eeacdad8918bcf0f1f7e90;hp=2054819dbf88099deba7b770f89d6820a2bbd83c;hpb=d19e80ca9777c9689d90c5faa6249fbfb8d55408;p=collectd.git

diff --git a/src/snmp_agent.c b/src/snmp_agent.c
index 2054819d..bb4a7e42 100644
--- a/src/snmp_agent.c
+++ b/src/snmp_agent.c
@@ -1,7 +1,7 @@
 /**
  * collectd - src/snmp_agent.c
  *
- * Copyright(c) 2017 Intel Corporation. All rights reserved.
+ * Copyright(c) 2017-2018 Intel Corporation. All rights reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -29,8 +29,8 @@
 
 #include "collectd.h"
 
-#include "common.h"
-#include "utils_avltree.h"
+#include "utils/avltree/avltree.h"
+#include "utils/common/common.h"
 #include "utils_cache.h"
 #include "utils_llist.h"
 #include <regex.h>
@@ -101,7 +101,7 @@ struct table_definition_s {
                                              will be split into sepearate
                                              tokens */
 
-  _Bool tokens_done; /* Set to 1 when all tokens are generated */
+  bool tokens_done; /* Set to true when all tokens are generated */
 };
 typedef struct table_definition_s table_definition_t;
 
@@ -134,7 +134,7 @@ struct snmp_agent_ctx_s {
 typedef struct snmp_agent_ctx_s snmp_agent_ctx_t;
 
 static snmp_agent_ctx_t *g_agent;
-const char *const index_opts[MAX_KEY_SOURCES] = {
+static const char *index_opts[MAX_KEY_SOURCES] = {
     "Hostname", "Plugin", "PluginInstance", "Type", "TypeInstance"};
 
 #define CHECK_DD_TYPE(_dd, _p, _pi, _t, _ti)                                   \
@@ -172,7 +172,7 @@ static int snmp_agent_oid_to_string(char *buf, size_t buf_size,
   char *oid_str_ptr[MAX_OID_LEN];
 
   for (size_t i = 0; i < o->oid_len; i++) {
-    snprintf(oid_str[i], sizeof(oid_str[i]), "%lu", (unsigned long)o->oid[i]);
+    ssnprintf(oid_str[i], sizeof(oid_str[i]), "%lu", (unsigned long)o->oid[i]);
     oid_str_ptr[i] = oid_str[i];
   }
 
@@ -340,9 +340,8 @@ static int snmp_agent_validate_config(void) {
   return 0;
 }
 
-static int snmp_agent_parse_index_key(const char *input, char *regex,
-                                      regex_t *regex_info, int gi,
-                                      regmatch_t *m) {
+static int snmp_agent_parse_index_key(const char *input, regex_t *regex_info,
+                                      int gi, regmatch_t *m) {
   regmatch_t matches[MAX_MATCHES];
 
   int ret = regexec(regex_info, input, MAX_MATCHES, matches, 0);
@@ -369,35 +368,51 @@ static int snmp_agent_parse_index_key(const char *input, char *regex,
 static int snmp_agent_create_token(char const *input, int t_off, int n,
                                    c_avl_tree_t *tree,
                                    netsnmp_variable_list *index_key) {
+  assert(tree != NULL);
+
   token_t *token = malloc(sizeof(*token));
+
+  if (token == NULL)
+    goto error;
+
   int *offset = malloc(sizeof(*offset));
-  int ret = 0;
 
-  assert(tree != NULL);
+  if (offset == NULL)
+    goto free_token_error;
 
-  if (token == NULL || offset == NULL)
-    goto error;
+  int ret = 0;
 
   token->key = index_key;
-  token->str = strndup(input + t_off, n);
+  input += t_off;
+  size_t len = strlen(input);
+
+  if (n < len)
+    len = n;
+
+  token->str = malloc(len + 1);
 
   if (token->str == NULL)
-    goto error;
+    goto free_offset_error;
 
+  /* copy at most n bytes from input with offset t_off into token->str */
+  sstrncpy(token->str, input, len + 1);
   *offset = t_off;
   ret = c_avl_insert(tree, (void *)offset, (void *)token);
 
-  if (ret != 0)
-    goto error;
+  if (ret == 0)
+    return 0;
 
-  return 0;
+  sfree(token->str);
 
-error:
+free_offset_error:
+  sfree(offset);
 
-  ERROR(PLUGIN_NAME ": Could not allocate memory to create token");
-  sfree(token->str);
+free_token_error:
   sfree(token);
-  sfree(offset);
+
+error:
+  ERROR(PLUGIN_NAME ": Could not allocate memory to create token");
+
   return -1;
 }
 
@@ -486,7 +501,6 @@ static int snmp_agent_fill_index_list(table_definition_t *td,
     /* var should never be NULL */
     assert(key != NULL);
     ptr = NULL;
-    ret = 0;
     const index_key_src_t source = td->index_keys[i].source;
     c_avl_tree_t *const tokens = td->tokens[source];
     /* Generating list filled with all data necessary to generate an OID */
@@ -510,16 +524,13 @@ static int snmp_agent_fill_index_list(table_definition_t *td,
       ERROR(PLUGIN_NAME ": Unknown index key source provided");
       return -EINVAL;
     }
-    if (ret != 0)
-      return -EINVAL;
 
     /* Parsing input string if necessary */
     if (td->index_keys[i].regex) {
-      regmatch_t m = {-1, -1};
+      regmatch_t m;
 
       /* Parsing input string */
-      ret = snmp_agent_parse_index_key(ptr, td->index_keys[i].regex,
-                                       &td->index_keys[i].regex_info,
+      ret = snmp_agent_parse_index_key(ptr, &td->index_keys[i].regex_info,
                                        td->index_keys[i].group, &m);
       if (ret != 0) {
         ERROR(PLUGIN_NAME ": Error executing regex");
@@ -527,7 +538,7 @@ static int snmp_agent_fill_index_list(table_definition_t *td,
       }
 
       /* Tokenizing input string if not done yet */
-      if (td->tokens_done == 0)
+      if (td->tokens_done == false)
         ret = snmp_agent_tokenize(ptr, tokens, &m, key);
 
       if (ret != 0)
@@ -535,17 +546,35 @@ static int snmp_agent_fill_index_list(table_definition_t *td,
 
       if (td->index_keys[i].type == ASN_INTEGER) {
         int val = strtol(ptr + m.rm_so, NULL, 0);
+
+#ifdef HAVE_NETSNMP_OLD_API
+        ret = snmp_set_var_value(key, (const u_char *)&val, sizeof(val));
+#else
         ret = snmp_set_var_value(key, &val, sizeof(val));
+#endif
       } else
+#ifdef HAVE_NETSNMP_OLD_API
+        ret = snmp_set_var_value(key, (const u_char *)(ptr + m.rm_so),
+                                 m.rm_eo - m.rm_so);
+#else
         ret = snmp_set_var_value(key, ptr + m.rm_so, m.rm_eo - m.rm_so);
+#endif
     } else
+#ifdef HAVE_NETSNMP_OLD_API
+      ret = snmp_set_var_value(key, (const u_char *)ptr, strlen(ptr));
+#else
       ret = snmp_set_var_value(key, ptr, strlen(ptr));
+#endif
+
+    if (ret != 0)
+      return -1;
+
     key = key->next_variable;
   }
 
   /* Tokens for all source strings are generated */
   for (i = 0; i < MAX_KEY_SOURCES; i++)
-    td->tokens_done = 1;
+    td->tokens_done = true;
 
   return 0;
 }
@@ -646,34 +675,39 @@ static int snmp_agent_unregister_oid_string(oid_t *oid,
   return snmp_agent_unregister_oid(&new_oid);
 }
 
-static int snmp_agent_table_data_remove(data_definition_t *dd,
-                                        table_definition_t *td,
-                                        oid_t **index_oid) {
+static void snmp_agent_table_data_remove(data_definition_t *dd,
+                                         table_definition_t *td,
+                                         oid_t *index_oid) {
   int *index = NULL;
   oid_t *ind_oid = NULL;
 
   if (td->index_oid.oid_len) {
-    if ((c_avl_get(td->instance_index, *index_oid, (void **)&index) != 0) ||
+    if ((c_avl_get(td->instance_index, index_oid, (void **)&index) != 0) ||
         (c_avl_get(td->index_instance, index, NULL) != 0))
-      return 0;
+      return;
   } else {
-    if (c_avl_get(td->instance_index, *index_oid, NULL) != 0)
-      return 0;
+    if (c_avl_get(td->instance_index, index_oid, NULL) != 0)
+      return;
   }
 
   pthread_mutex_lock(&g_agent->agentx_lock);
 
+  int reg_oids = -1; /* Number of registered oids for given instance */
+
   for (size_t i = 0; i < dd->oids_len; i++) {
     if (td->index_oid.oid_len)
       snmp_agent_unregister_oid_index(&dd->oids[i], *index);
     else
-      snmp_agent_unregister_oid_string(&dd->oids[i], *index_oid);
+      snmp_agent_unregister_oid_string(&dd->oids[i], index_oid);
+
+    reg_oids =
+        snmp_agent_update_instance_oids(td->instance_oids, index_oid, -1);
   }
 
   /* Checking if any metrics are left registered */
-  if (snmp_agent_update_instance_oids(td->instance_oids, *index_oid, -1) > 0) {
+  if (reg_oids != 0) {
     pthread_mutex_unlock(&g_agent->agentx_lock);
-    return 0;
+    return;
   }
 
   /* All metrics have been unregistered. Unregistering index key OIDs */
@@ -688,7 +722,7 @@ static int snmp_agent_table_data_remove(data_definition_t *dd,
       if (td->index_oid.oid_len)
         snmp_agent_unregister_oid_index(&idd->oids[i], *index);
       else
-        snmp_agent_unregister_oid_string(&idd->oids[i], *index_oid);
+        snmp_agent_unregister_oid_string(&idd->oids[i], index_oid);
 
     if (++keys_processed >= td->index_keys_len)
       break;
@@ -700,38 +734,36 @@ static int snmp_agent_table_data_remove(data_definition_t *dd,
   char index_str[DATA_MAX_NAME_LEN];
 
   if (index == NULL)
-    snmp_agent_oid_to_string(index_str, sizeof(index_str), *index_oid);
+    snmp_agent_oid_to_string(index_str, sizeof(index_str), index_oid);
   else
-    snprintf(index_str, sizeof(index_str), "%d", *index);
+    ssnprintf(index_str, sizeof(index_str), "%d", *index);
 
   notification_t n = {
       .severity = NOTIF_WARNING, .time = cdtime(), .plugin = PLUGIN_NAME};
   sstrncpy(n.host, hostname_g, sizeof(n.host));
-  snprintf(n.message, sizeof(n.message),
-           "Removed data row from table %s with index %s", td->name, index_str);
+  ssnprintf(n.message, sizeof(n.message),
+            "Removed data row from table %s with index %s", td->name,
+            index_str);
   DEBUG(PLUGIN_NAME ": %s", n.message);
   plugin_dispatch_notification(&n);
 
   int *val = NULL;
 
-  c_avl_remove(td->instance_oids, *index_oid, NULL, (void **)&val);
+  c_avl_remove(td->instance_oids, index_oid, NULL, (void **)&val);
   sfree(val);
 
-  if (td->index_oid.oid_len) {
+  if (index != NULL) {
     pthread_mutex_lock(&g_agent->agentx_lock);
     snmp_agent_unregister_oid_index(&td->index_oid, *index);
     pthread_mutex_unlock(&g_agent->agentx_lock);
 
     c_avl_remove(td->index_instance, index, NULL, (void **)&ind_oid);
-    c_avl_remove(td->instance_index, *index_oid, NULL, (void **)&index);
+    c_avl_remove(td->instance_index, index_oid, NULL, (void **)&index);
     sfree(index);
     sfree(ind_oid);
   } else {
-    c_avl_remove(td->instance_index, *index_oid, NULL, NULL);
-    sfree(*index_oid);
+    c_avl_remove(td->instance_index, index_oid, NULL, NULL);
   }
-
-  return 0;
 }
 
 static int snmp_agent_clear_missing(const value_list_t *vl,
@@ -744,15 +776,22 @@ static int snmp_agent_clear_missing(const value_list_t *vl,
 
     for (llentry_t *de = llist_head(td->columns); de != NULL; de = de->next) {
       data_definition_t *dd = de->value;
-      oid_t *index_oid = (oid_t *)calloc(1, sizeof(*index_oid));
-      int ret;
 
       if (!dd->is_index_key) {
         if (CHECK_DD_TYPE(dd, vl->plugin, vl->plugin_instance, vl->type,
                           vl->type_instance)) {
-          ret = snmp_agent_generate_index(td, vl, index_oid);
+          oid_t *index_oid = calloc(1, sizeof(*index_oid));
+
+          if (index_oid == NULL) {
+            ERROR(PLUGIN_NAME ": Could not allocate memory for index_oid");
+            return -ENOMEM;
+          }
+
+          int ret = snmp_agent_generate_index(td, vl, index_oid);
+
           if (ret == 0)
-            ret = snmp_agent_table_data_remove(dd, td, &index_oid);
+            snmp_agent_table_data_remove(dd, td, index_oid);
+          sfree(index_oid);
 
           return ret;
         }
@@ -898,6 +937,7 @@ static void snmp_agent_free_table(table_definition_t **td) {
 
 static int snmp_agent_parse_oid_index_keys(const table_definition_t *td,
                                            oid_t *index_oid) {
+  assert(index_oid != NULL);
   int ret = parse_oid_indexes(index_oid->oid, index_oid->oid_len,
                               td->index_list_cont);
   if (ret != SNMPERR_SUCCESS)
@@ -906,7 +946,6 @@ static int snmp_agent_parse_oid_index_keys(const table_definition_t *td,
 }
 
 static int snmp_agent_build_name(char **name, c_avl_tree_t *tokens) {
-
   int *pos;
   token_t *tok;
   char str[DATA_MAX_NAME_LEN];
@@ -919,19 +958,19 @@ static int snmp_agent_build_name(char **name, c_avl_tree_t *tokens) {
   }
 
   while (c_avl_iterator_next(it, (void **)&pos, (void **)&tok) == 0) {
-    strncat(out, tok->str, strlen(tok->str));
+    strncat(out, tok->str, DATA_MAX_NAME_LEN - strlen(out) - 1);
     if (tok->key != NULL) {
       if (tok->key->type == ASN_INTEGER) {
-        snprintf(str, sizeof(str), "%ld", *tok->key->val.integer);
-        strncat(out, str, strlen(str));
-      } else { /* OCTET_STR */
+        ssnprintf(str, sizeof(str), "%ld", *tok->key->val.integer);
+        strncat(out, str, DATA_MAX_NAME_LEN - strlen(out) - 1);
+      } else /* OCTET_STR */
         strncat(out, (char *)tok->key->val.string,
-                strlen((char *)tok->key->val.string));
-      }
+                DATA_MAX_NAME_LEN - strlen(out) - 1);
     }
   }
-  *name = strdup(out);
+
   c_avl_iterator_destroy(it);
+  *name = strdup(out);
 
   if (*name == NULL) {
     ERROR(PLUGIN_NAME ": Could not allocate memory");
@@ -975,7 +1014,7 @@ static int snmp_agent_format_name(char *name, int name_len,
         }
 
         if (td->index_keys[i].type == ASN_INTEGER) {
-          snprintf(str, sizeof(str), "%ld", *key->val.integer);
+          ssnprintf(str, sizeof(str), "%ld", *key->val.integer);
           fields[source] = str;
         } else /* OCTET_STR */
           fields[source] = (char *)key->val.string;
@@ -1024,12 +1063,24 @@ static int snmp_agent_form_reply(struct netsnmp_request_info_s *requests,
     requests->requestvb->type = td->index_keys[dd->index_key_pos].type;
 
     if (requests->requestvb->type == ASN_INTEGER)
+#ifdef HAVE_NETSNMP_OLD_API
+      snmp_set_var_typed_value(requests->requestvb, requests->requestvb->type,
+                               (const u_char *)key->val.integer,
+                               sizeof(*key->val.integer));
+#else
       snmp_set_var_typed_value(requests->requestvb, requests->requestvb->type,
                                key->val.integer, sizeof(*key->val.integer));
+#endif
     else /* OCTET_STR */
+#ifdef HAVE_NETSNMP_OLD_API
       snmp_set_var_typed_value(requests->requestvb, requests->requestvb->type,
                                (const u_char *)key->val.string,
                                strlen((const char *)key->val.string));
+#else
+      snmp_set_var_typed_value(requests->requestvb, requests->requestvb->type,
+                               key->val.string,
+                               strlen((const char *)key->val.string));
+#endif
 
     pthread_mutex_unlock(&g_agent->lock);
 
@@ -1370,10 +1421,14 @@ static int snmp_agent_config_data_oids(data_definition_t *dd,
       return -EINVAL;
     }
 
-  if (dd->oids != NULL)
-    sfree(dd->oids);
+  if (dd->oids != NULL) {
+    WARNING(PLUGIN_NAME ": OIDs can be configured only once for each data");
+    return -EINVAL;
+  }
+
   dd->oids_len = 0;
   dd->oids = calloc(ci->values_num, sizeof(*dd->oids));
+
   if (dd->oids == NULL)
     return -ENOMEM;
   dd->oids_len = (size_t)ci->values_num;
@@ -1455,7 +1510,7 @@ static int snmp_agent_config_index_key_source(table_definition_t *td,
   if (ret != 0)
     return -1;
 
-  _Bool match = 0;
+  bool match = false;
 
   for (int i = 0; i < MAX_KEY_SOURCES; i++) {
     if (strcasecmp(index_opts[i], (const char *)val) == 0) {
@@ -1475,7 +1530,7 @@ static int snmp_agent_config_index_key_source(table_definition_t *td,
 
   sfree(val);
   dd->index_key_pos = td->index_keys_len++;
-  dd->is_index_key = 1;
+  dd->is_index_key = true;
 
   return 0;
 }
@@ -1497,7 +1552,7 @@ static int snmp_agent_config_index_key_regex(table_definition_t *td,
   }
 
   index_key_src_t source = index_key->source;
-  if (td->tokens[source] == NULL && index_key->regex != NULL) {
+  if (td->tokens[source] == NULL) {
     td->tokens[source] =
         c_avl_create((int (*)(const void *, const void *))num_compare);
     if (td->tokens[source] == NULL) {
@@ -1554,14 +1609,14 @@ static int snmp_agent_config_table_column(table_definition_t *td,
   dd->shift = 0.0;
   /* NULL if it's a scalar */
   dd->table = td;
-  dd->is_index_key = 0;
+  dd->is_index_key = false;
 
   for (int i = 0; i < ci->children_num; i++) {
     oconfig_item_t *option = ci->children + i;
 
     /* First 3 options are reserved for table entry only */
     if (td != NULL && strcasecmp("IndexKey", option->key) == 0) {
-      dd->is_index_key = 1;
+      dd->is_index_key = true;
       option_tmp = option;
     } else if (strcasecmp("Plugin", option->key) == 0)
       ret = cf_util_get_string(option, &dd->plugin);
@@ -1608,6 +1663,8 @@ static int snmp_agent_config_table_column(table_definition_t *td,
   /* Append to column list in parent table */
   if (td != NULL)
     llist_append(td->columns, entry);
+  else
+    llentry_destroy(entry);
 
   return 0;
 }
@@ -1658,7 +1715,7 @@ static int snmp_agent_config_table(oconfig_item_t *ci) {
 
   for (int i = 0; i < MAX_KEY_SOURCES; i++)
     td->tokens[i] = NULL;
-  td->tokens_done = 0;
+  td->tokens_done = false;
 
   for (int i = 0; i < ci->children_num; i++) {
     oconfig_item_t *option = ci->children + i;
@@ -1780,7 +1837,7 @@ static int snmp_agent_set_vardata(void *data, size_t *data_len, u_char asn_type,
   case ASN_OCTET_STR:
     if (type == DS_TYPE_GAUGE) {
       char buf[DATA_MAX_NAME_LEN];
-      snprintf(buf, sizeof(buf), "%.2f", val->gauge);
+      ssnprintf(buf, sizeof(buf), "%.2f", val->gauge);
       if (*data_len < strlen(buf))
         return -EINVAL;
       *data_len = strlen(buf);
@@ -1829,68 +1886,67 @@ static int snmp_agent_update_instance_oids(c_avl_tree_t *tree, oid_t *index_oid,
 }
 
 static int snmp_agent_update_index(data_definition_t *dd,
-                                   table_definition_t *td, oid_t **index_oid) {
+                                   table_definition_t *td, oid_t *index_oid,
+                                   bool *free_index_oid) {
   int ret;
   int *index = NULL;
-  _Bool free_index_oid = 1;
+  int *value = NULL;
 
-  if (c_avl_get(td->instance_index, (void *)*index_oid, (void **)&index) != 0) {
-    free_index_oid = 0;
+  if (c_avl_get(td->instance_index, (void *)index_oid, (void **)&index) != 0) {
+    /* We'll keep index_oid stored in AVL tree */
+    *free_index_oid = false;
 
     /* need to generate index for the table */
     if (td->index_oid.oid_len) {
       index = calloc(1, sizeof(*index));
       if (index == NULL) {
-        sfree(*index_oid);
-        return -ENOMEM;
+        ret = -ENOMEM;
+        goto error;
       }
 
       *index = c_avl_size(td->instance_index) + 1;
 
-      ret = c_avl_insert(td->instance_index, *index_oid, index);
-      if (ret != 0) {
-        sfree(*index_oid);
-        sfree(index);
-        return ret;
-      }
+      ret = c_avl_insert(td->instance_index, index_oid, index);
+      if (ret != 0)
+        goto free_index;
 
-      ret = c_avl_insert(td->index_instance, index, *index_oid);
+      ret = c_avl_insert(td->index_instance, index, index_oid);
       if (ret < 0) {
         DEBUG(PLUGIN_NAME ": Failed to update index_instance for '%s' table",
               td->name);
-        c_avl_remove(td->instance_index, *index_oid, NULL, (void **)&index);
-        sfree(*index_oid);
-        sfree(index);
-        return ret;
+        goto remove_avl_index_oid;
       }
 
       ret = snmp_agent_register_oid_index(&td->index_oid, *index,
                                           snmp_agent_table_index_oid_handler);
       if (ret != 0)
-        return ret;
+        goto remove_avl_index;
     } else {
       /* instance as a key is required for any table */
-      ret = c_avl_insert(td->instance_index, *index_oid, NULL);
-      if (ret != 0) {
-        sfree(*index_oid);
-        return ret;
-      }
+      ret = c_avl_insert(td->instance_index, index_oid, NULL);
+      if (ret != 0)
+        goto error;
+    }
+
+    value = calloc(1, sizeof(*value));
+
+    if (value == NULL) {
+      ERROR(PLUGIN_NAME ": Failed to allocate memory");
+      ret = -ENOMEM;
+      goto unregister_index;
     }
 
-    int *value = calloc(1, sizeof(*value));
+    ret = c_avl_insert(td->instance_oids, index_oid, value);
 
-    ret = c_avl_insert(td->instance_oids, *index_oid, value);
     if (ret < 0) {
-      if (td->index_oid.oid_len) {
-        c_avl_remove(td->index_instance, index, NULL, NULL);
-      }
-      c_avl_remove(td->instance_index, *index_oid, NULL, (void **)&index);
-      sfree(index);
-      sfree(*index_oid);
+      DEBUG(PLUGIN_NAME ": Failed to update instance_oids for '%s' table",
+            td->name);
+      goto free_value;
     }
 
     int keys_processed = 0;
 
+    /* Registering index keys OIDs */
     for (llentry_t *de = llist_head(td->columns); de != NULL; de = de->next) {
       data_definition_t *idd = de->value;
       if (!idd->is_index_key)
@@ -1901,12 +1957,12 @@ static int snmp_agent_update_index(data_definition_t *dd,
           ret = snmp_agent_register_oid_index(&idd->oids[i], *index,
                                               snmp_agent_table_oid_handler);
         else
-          ret = snmp_agent_register_oid_string(&idd->oids[i], *index_oid,
+          ret = snmp_agent_register_oid_string(&idd->oids[i], index_oid,
                                                snmp_agent_table_oid_handler);
 
         if (ret != 0) {
           ERROR(PLUGIN_NAME ": Could not register OID");
-          return ret;
+          goto free_index;
         }
       }
 
@@ -1922,39 +1978,55 @@ static int snmp_agent_update_index(data_definition_t *dd,
       ret = snmp_agent_register_oid_index(&dd->oids[i], *index,
                                           snmp_agent_table_oid_handler);
     else
-      ret = snmp_agent_register_oid_string(&dd->oids[i], *index_oid,
+      ret = snmp_agent_register_oid_string(&dd->oids[i], index_oid,
                                            snmp_agent_table_oid_handler);
 
     if (ret < 0)
-      return ret;
+      goto free_index;
     else if (ret == OID_EXISTS)
       break;
-    else
-      ret = snmp_agent_update_instance_oids(td->instance_oids, *index_oid, 1);
+    else if (snmp_agent_update_instance_oids(td->instance_oids, index_oid, 1) <
+             0)
+      goto free_index;
   }
 
   if (ret != OID_EXISTS) {
     char index_str[DATA_MAX_NAME_LEN];
 
     if (index == NULL)
-      snmp_agent_oid_to_string(index_str, sizeof(index_str), *index_oid);
+      snmp_agent_oid_to_string(index_str, sizeof(index_str), index_oid);
     else
-      snprintf(index_str, sizeof(index_str), "%d", *index);
+      ssnprintf(index_str, sizeof(index_str), "%d", *index);
 
     notification_t n = {
         .severity = NOTIF_OKAY, .time = cdtime(), .plugin = PLUGIN_NAME};
     sstrncpy(n.host, hostname_g, sizeof(n.host));
-    snprintf(n.message, sizeof(n.message),
-             "Data added to table %s with index %s", td->name, index_str);
+    ssnprintf(n.message, sizeof(n.message),
+              "Data added to table %s with index %s", td->name, index_str);
     DEBUG(PLUGIN_NAME ": %s", n.message);
 
     plugin_dispatch_notification(&n);
   }
 
-  if (free_index_oid)
-    sfree(*index_oid);
-
   return 0;
+
+free_value:
+  sfree(value);
+unregister_index:
+  if (td->index_oid.oid_len)
+    snmp_agent_unregister_oid_index(index_oid, *index);
+remove_avl_index:
+  if (td->index_oid.oid_len)
+    c_avl_remove(td->index_instance, index, NULL, NULL);
+remove_avl_index_oid:
+  c_avl_remove(td->instance_index, index_oid, NULL, NULL);
+free_index:
+  if (index != NULL)
+    sfree(index);
+error:
+  *free_index_oid = true;
+
+  return ret;
 }
 
 static int snmp_agent_write(value_list_t const *vl) {
@@ -1966,18 +2038,26 @@ static int snmp_agent_write(value_list_t const *vl) {
 
     for (llentry_t *de = llist_head(td->columns); de != NULL; de = de->next) {
       data_definition_t *dd = de->value;
-      oid_t *index_oid = (oid_t *)calloc(1, sizeof(*index_oid));
-      int ret;
-
-      if (index_oid == NULL)
-        return -ENOMEM;
 
       if (!dd->is_index_key) {
         if (CHECK_DD_TYPE(dd, vl->plugin, vl->plugin_instance, vl->type,
                           vl->type_instance)) {
-          ret = snmp_agent_generate_index(td, vl, index_oid);
+          oid_t *index_oid = calloc(1, sizeof(*index_oid));
+          bool free_index_oid = true;
+
+          if (index_oid == NULL) {
+            ERROR(PLUGIN_NAME ": Could not allocate memory for index_oid");
+            return -ENOMEM;
+          }
+
+          int ret = snmp_agent_generate_index(td, vl, index_oid);
+
           if (ret == 0)
-            ret = snmp_agent_update_index(dd, td, &index_oid);
+            ret = snmp_agent_update_index(dd, td, index_oid, &free_index_oid);
+
+          /* Index exists or update failed */
+          if (free_index_oid)
+            sfree(index_oid);
 
           return ret;
         }
@@ -2123,7 +2203,12 @@ static int snmp_agent_register_oid(oid_t *oid, Netsnmp_Node_Handler *handler) {
   if (c_avl_get(g_agent->registered_oids, (void *)oid, NULL) == 0)
     return OID_EXISTS;
   else {
-    oid_t *new_oid = calloc(1, sizeof(*oid));
+    oid_t *new_oid = calloc(1, sizeof(*new_oid));
+    if (new_oid == NULL) {
+      ERROR(PLUGIN_NAME ": Could not allocate memory to register new OID");
+      return -ENOMEM;
+    }
+
     memcpy(new_oid, oid, sizeof(*oid));
 
     int ret = c_avl_insert(g_agent->registered_oids, (void *)new_oid, NULL);