<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
<p>There were found few known regressions in 2.86 release. Could you
try latest test release of version 2.87, if that crash would still
occur? Multiple of issues were fixed already.<br>
</p>
<div class="moz-cite-prefix">On 5/7/22 13:16, 韩冰 wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CAJGq1st60uYb5QH_aKYEq9GnqtRvkuaR_sz6yDzC+tRhwr_tAA@mail.gmail.com">
<div dir="ltr">
<div dir="ltr" data-smartmail="gmail_signature">
<div dir="ltr">
<div>
<div>Hello everyone,</div>
</div>
<div>I found a core dump issue when I use dnsmasq as a DHCP
server (Version 2.86, running on Linux). My setup
and reproduction step is as follows.</div>
<div>Dnsmasq main config</div>
<blockquote class="gmail_quote"># Common Configure<br>
pid-file=/var/run/dnsmasq.pid<br>
log-facility=/var/log/dnsmasq.log<br>
user=root<br>
group=root<br>
interface=eth0<br>
<br>
# DNS Server Configure<br>
no-hosts<br>
no-resolv<br>
log-queries=extra<br>
port=53<br>
<br>
# DHCP Server Configure<br>
log-dhcp<br>
dhcp-range=172.17.12.128,static,255.255.255.192 # Change
the network address and subnet mask.<br>
dhcp-hostsfile=/etc/dnsmasq/dhcp-hosts<br>
dhcp-optsfile=/etc/dnsmasq/dhcp-options<br>
dhcp-vendorclass=set:pxe-bios-x86,PXEClient:Arch:00000<br>
dhcp-vendorclass=set:pxe-uefi-amd64,PXEClient:Arch:00007<br>
dhcp-vendorclass=set:pxe-uefi-amd64,PXEClient:Arch:00009<br>
dhcp-boot=tag:pxe-bios-x86,pxelinux.0,pxeserver<br>
dhcp-boot=tag:pxe-uefi-amd64,bootnetx64.efi,pxeserver<br>
dhcp-ignore=tag:!known<br>
</blockquote>
<div>External DHCP host file</div>
<blockquote class="gmail_quote">08:c0:eb:cb:MM:NN,id:*,set:mytag,172.17.12.XXX,XXX-01,5m </blockquote>
<div>External DHCP options file</div>
<blockquote class="gmail_quote">tag:mytag,option:netmask,255.255.255.128<br>
tag:mytag,option:router,172.17.12.190<br>
tag:mytag,option:dns-server,172.16.0.XXX<br>
tag:mytag,option:ntp-server,172.16.0.XXX<br>
tag:mytag,option:domain-name,mydomain<br>
</blockquote>
<div>Reproduction step is <br>
</div>
<div>First start dnsmasq with the config shown above, </div>
<div>Then use 08:c0:eb:cb:MM:NN to obtain an IP address from
dnsmasq server.</div>
<div>After we can see lease of 08:c0:eb:cb:MM:NN
in dnsmasq.leases, send signal HUP to dnsmasq,</div>
<div>Now I got dnsmasq core dumped and traceback is
following</div>
<blockquote class="gmail_quote">#0 __GI_raise
(sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50<br>
#1 0x00007f858837f535 in __GI_abort () at abort.c:79<br>
#2 0x00007f85883d6518 in __libc_message
(action=action@entry=do_abort,
fmt=fmt@entry=0x7f85884e028d "%s\n")<br>
at ../sysdeps/posix/libc_fatal.c:181<br>
#3 0x00007f85883dcc3a in malloc_printerr
(str=str@entry=0x7f85884e1fe0 "double free or corruption
(out)") at malloc.c:5359<br>
#4 0x00007f85883de770 in _int_free (av=0x7f8588517c40
<main_arena>, p=0x7ffd7d6e79a0,
have_lock=<optimized out>) at malloc.c:4321<br>
#5 0x0000000000410187 in dhcp_netid_free
(nid=0x7ffd7d6e79b0) at option.c:1019<br>
#6 0x0000000000410258 in dhcp_netid_list_free (netid=0x0)
at option.c:1050<br>
#7 0x00000000004102c9 in dhcp_config_free
(config=0x2273950) at option.c:1068<br>
#8 0x000000000041c313 in clear_dynamic_conf () at
option.c:5186<br>
#9 0x000000000041c3bd in reread_dhcp () at option.c:5219<br>
#10 0x0000000000428a11 in clear_cache_and_reload
(now=1650633404) at dnsmasq.c:1694<br>
#11 0x0000000000428303 in async_event (pipe=10,
now=1650633404) at dnsmasq.c:1450<br>
#12 0x0000000000427cf4 in main (argc=3,
argv=0x7ffd7d6e81a8) at dnsmasq.c:1193<br>
</blockquote>
<div>It looks like there is some memory management issue
about dhcp tag</div>
<div>I found another related fact that if I just start
dnsmasq and reload it, or dnsmasq only receive dhcp packet
from UNKNOWN mac address and reload it, dnsmasq will NOT
core dumped when reloading, so I guess that the issue
maybe related to progress of DHCP packet</div>
<div>That is all about I found about core dumped issue when
reloading, I'm looking forward for someone found similar
problem or have idea about this issue</div>
<div><br>
</div>
<div>Thanks</div>
<div>Han Bing</div>
</div>
</div>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<pre class="moz-quote-pre" wrap="">_______________________________________________
Dnsmasq-discuss mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Dnsmasq-discuss@lists.thekelleys.org.uk">Dnsmasq-discuss@lists.thekelleys.org.uk</a>
<a class="moz-txt-link-freetext" href="https://lists.thekelleys.org.uk/cgi-bin/mailman/listinfo/dnsmasq-discuss">https://lists.thekelleys.org.uk/cgi-bin/mailman/listinfo/dnsmasq-discuss</a>
</pre>
</blockquote>
<pre class="moz-signature" cols="72">--
Petr Menšík
Software Engineer
Red Hat, <a class="moz-txt-link-freetext" href="http://www.redhat.com/">http://www.redhat.com/</a>
email: <a class="moz-txt-link-abbreviated" href="mailto:pemensik@redhat.com">pemensik@redhat.com</a>
PGP: DFCF908DB7C87E8E529925BC4931CA5B6C9FC5CB</pre>
</body>
</html>