Thanks for the detailed analysis.
diff below should fix it.
martijn@
On Sun, 2021-10-24 at 22:44 +0100, Stuart Henderson wrote:
> ooops, sorry not trondd, it was jhuldtgren who spotted it!
>
> On 2021/10/24 22:26, Stuart Henderson wrote:
> > trondd noticed a startup problem with snmpd on mips64 but didn't see
> > them on amd64 and wondered if it was arch-specific, I had a go at
> > reproducing and see it very often on aarch64 and also sometimes on
> > amd64.
> >
> > Any setting of "trap receiver $ip snmpv2c community $community"
> > triggers the problem:
> >
> > # for i in `jot 20`; do snmpd -nvf /etc/snmpd.conf; done
> > trap receiver: missing community
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > trap receiver: missing community
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > configuration ok
> > trap receiver: missing community
> >
> > Additionally even when configuration is accepted, the community is set
> > to junk
> >
> > 822 tr->ta_oid = $2;
> > 823 tr->ta_version = $3.type;
> >
> > with snmpv2c ta_version is set to 1
> >
> > 824 if ($3.type == ADDRESS_FLAG_SNMPV2) {
> >
> > so this branch isn't taken
> >
> > 825 (void)strlcpy(tr->ta_community,
> > $3.data,
> > 826 sizeof(tr->ta_community));
> > 827 free($3.data);
> > 828 } else {
> > 829 tr->ta_usmusername = $3.data;
> > 830 tr->ta_seclevel = $3.value;
> > 831 }
> >
> > at this point ta_usmusername is set to the community and ta_community
> > is junk.
> >
> > 810 if ($4 != NULL) {
> > (gdb)
> > 823 tr->ta_version = $3.type;
> > (gdb)
> > 824 if ($3.type == ADDRESS_FLAG_SNMPV2) {
> > (gdb) p *tr
> > $3 = {ta_ss = {ss_len = 16 '\020', ss_family = 2 '\002', __ss_pad1 =
> > "\000\242\303_\273T", __ss_pad2 = 0,
> > __ss_pad3 = "\002\000\000\000\001\000\000\000\001\000\000\000\a",
> > '\000' <repeats 226 times>}, ta_sslocal = {
> > ss_len = 0 '\000', ss_family = 0 '\000', __ss_pad1 =
> > "\000\000\000\000\000", __ss_pad2 = 0,
> > __ss_pad3 = '\000' <repeats 239 times>}, ta_version = 1, {ta_community
> > = '\000' <repeats 483 times>, {
> > ta_usmusername = 0x0, ta_usmuser = 0x0, ta_seclevel = 0}}, ta_oid =
> > 0x0, entry = {tqe_next = 0x0,
> > tqe_prev = 0x0}}
> > (gdb) n
> > 829 tr->ta_usmusername = $3.data;
> > (gdb)
> > 830 tr->ta_seclevel = $3.value;
> > (gdb)
> > 832 TAILQ_INSERT_TAIL(&(conf->sc_trapreceivers),
> > tr, entry);
> > (gdb) p *tr
> > $4 = {ta_ss = {ss_len = 16 '\020', ss_family = 2 '\002', __ss_pad1 =
> > "\000\242\303_\273T", __ss_pad2 = 0,
> > __ss_pad3 = "\002\000\000\000\001\000\000\000\001\000\000\000\a",
> > '\000' <repeats 226 times>}, ta_sslocal = {
> > ss_len = 0 '\000', ss_family = 0 '\000', __ss_pad1 =
> > "\000\000\000\000\000", __ss_pad2 = 0,
> > __ss_pad3 = '\000' <repeats 239 times>}, ta_version = 1, {
> > ta_community = "\340\035a\250O\005", '\000' <repeats 477 times>, {
> > ta_usmusername = 0x54fa8611de0 "zzzzzzzzzzzzzzzzzz", ta_usmuser =
> > 0x0, ta_seclevel = 0}}, ta_oid = 0x0,
> > entry = {tqe_next = 0x0, tqe_prev = 0x0}}
> >
> >
> >
Index: parse.y
===================================================================
RCS file: /cvs/src/usr.sbin/snmpd/parse.y,v
retrieving revision 1.71
diff -u -p -r1.71 parse.y
--- parse.y 20 Oct 2021 16:00:47 -0000 1.71
+++ parse.y 25 Oct 2021 09:09:14 -0000
@@ -821,7 +821,7 @@ hostdef : STRING hostoid hostauth srcad
}
tr->ta_oid = $2;
tr->ta_version = $3.type;
- if ($3.type == ADDRESS_FLAG_SNMPV2) {
+ if ($3.type == SNMP_V2) {
(void)strlcpy(tr->ta_community, $3.data,
sizeof(tr->ta_community));
free($3.data);
