Merge branch 'bugfix/http_client_redirection' into 'master'

Fix url redirection issue

See merge request idf/esp-idf!4623

components/esp_http_client/esp_http_client.c

@@ -661,7 +661,9 @@ esp_err_t esp_http_client_set_url(esp_http_client_handle_t client, const char *u
         ESP_LOGE(TAG, "Error parse url %s", url);
         return ESP_ERR_INVALID_ARG;
     }
-    old_host = client->connection_info.host;
+    if (client->connection_info.host) {
+        old_host = strdup(client->connection_info.host);
+    }
     old_port = client->connection_info.port;
 
     if (purl.field_data[UF_HOST].len) {
@@ -673,11 +675,17 @@ esp_err_t esp_http_client_set_url(esp_http_client_handle_t client, const char *u
             && strcasecmp(old_host, (const void *)client->connection_info.host) != 0) {
         ESP_LOGD(TAG, "New host assign = %s", client->connection_info.host);
         if (esp_http_client_set_header(client, "Host", client->connection_info.host) != ESP_OK) {
+            free(old_host);
             return ESP_ERR_NO_MEM;
         }
         esp_http_client_close(client);
     }
 
+    if (old_host) {
+        free(old_host);
+        old_host = NULL;
+    }
+
     if (purl.field_data[UF_SCHEMA].len) {
         http_utils_assign_string(&client->connection_info.scheme, url + purl.field_data[UF_SCHEMA].off, purl.field_data[UF_SCHEMA].len);
         HTTP_MEM_CHECK(TAG, client->connection_info.scheme, return ESP_ERR_NO_MEM);