[pihole] [unbound] [DNSMASQ] validation failed: resource limit exeeded

DL6ER · February 18, 2024, 7:21pm

Okay, so the warning is indeed a bug and shouldn't be printed at all. I will contact the dnsmasq maintainer to check what the best solution should look like and keep you updated!

Pi-hole will then likely push out an FTL v5.25.1 soon after. Thank you all for helping characterizing and confirming this bug! At this point I don't need anything more from you.

Summary: you can ignore the warning for now as it printed due to an inaccurate condition.

edit For the curious: this is how the bug is triggered in the code:

github.com/pi-hole/FTL

src/dnsmasq/forward.c

4f92b48ff


      
          /* If all replies to a query are REFUSED, give up. */
          if (RCODE(header) == REFUSED)
            status = STAT_ABANDONED;

github.com/pi-hole/FTL

src/dnsmasq/forward.c

4f92b48ff


      
          if (STAT_ISEQUAL(status, STAT_ABANDONED))
            log_resource = 1;

github.com/pi-hole/FTL

src/dnsmasq/forward.c

4f92b48ff


      
            if (log_resource)
              {
                /* Log the actual validation that made us barf. */
                unsigned char *p = (unsigned char *)(header+1);
                if  (extract_name(header, plen, &p, daemon->namebuff, 0, 4) == 1)
          	my_syslog(LOG_WARNING, _("validation of %s failed: resource limit exceeded."),
          		  daemon->namebuff[0] ? daemon->namebuff : ".");
              }

It is unclear at this point how to fix this best, but we will probably change the second quoted code block to not set log_resource in the REFUSED case.