Fix watchdog ping probes fail with long hostnames due to small buffer.

per 516.

diff --git a/src/watchdog/wd_ping.c b/src/watchdog/wd_ping.c
index 67e9ecbe44e0ac3d841328dd7687cc1794d751fb..d9dc9810b59c449470ad83b61becf9e9f00bc706 100644 (file)
--- a/src/watchdog/wd_ping.c
+++ b/src/watchdog/wd_ping.c
@@ -6,7 +6,7 @@
  * pgpool: a language independent connection pool server for PostgreSQL
  * written by Tatsuo Ishii
  *
- * Copyright (c) 2003-2016     PgPool Global Development Group
+ * Copyright (c) 2003-2020     PgPool Global Development Group
  *
  * Permission to use, copy, modify, and distribute this software and
  * its documentation for any purpose and without fee is hereby
@@ -174,28 +174,31 @@ wd_get_ping_result(char *hostname, int exit_status, int outfd)
        }
        else
        {
-               char            result[WD_MAX_PING_RESULT];
-               int                     i = 0;
-               int                     r_size = 0;
+               StringInfoData  result;
+               char            buf[WD_MAX_PING_RESULT];
+               int             r_size = 0;
 
                ereport(DEBUG1,
                                (errmsg("watchdog ping process for host \"%s\" exited successfully", hostname)));
 
-               while (((r_size = read(outfd, &result[i], sizeof(result) - i - 1)) > 0) && (errno == EINTR))
+               initStringInfo(&result);
+               while ((r_size = read(outfd, &buf, sizeof(buf) - 1)) > 0)
                {
-                       i += r_size;
+                       buf[r_size] = '\0';
+                       appendStringInfoString(&result, buf);
                }
-               result[sizeof(result) - 1] = '\0';
                /* Check whether average RTT >= 0 */
-               if (get_result(result) >= 0)
+               if (get_result(result.data) >= 0)
                {
                        ereport(DEBUG1,
                                        (errmsg("watchdog succeeded to ping a host \"%s\"", hostname)));
+                       pfree(result.data);
                        return true;
                }
                ereport(WARNING,
                                (errmsg("ping host\"%s\" failed", hostname),
                                 errdetail("average RTT value is not greater than zero")));
+               pfree(result.data);
        }
        return false;
 }