The real question here is what is spawning multiple instances of dnsmasq. That's wrong...
Ok, so dnsmasq forks itself to handle tcp connections...
1 Like
If that's the case, check if it's possible to set a maximum of child processes.
This is defined to be #define MAX_PROCS 20 in dnsmasq's config.h
That's kind of hard to redefine once compiled, I was looking for a conf file or command line parameter.
Yep, agreed - there is no conf file option for this
Definitely no command line parameter. Just looked at the code. dnsmasq would need to be patched to allow for a configurable MAX_PROCS set on the command line.
If you roll your own openwrt or can build dnsmasq from source, here's a patch to dnsmasq that implements a maximum number of child processes. It's on dnsmasq-2.84, so the trunk version of dnsmasq. It's a relatively trivial patch....
With this patch, dnsmasq will accept a new configuration file parameter or command line long-form argument max-procs=<number>. Just put the parameter in /etc/dnsmasq.conf.
The configured maximum number of child processes can not go above the MAX_PROCS value defined to be 20, so this argument really only serves to allow you to reduce the maximum number of processes.
I've tested it as far as making sure that the set value is used correctly. Be interesting to see your mileage and if it actually fixes your problem or not....
If you don't have a full buildroot, you can just use the openwrt SDK to compile a patched version of dnsmasq. Put the file below into package/network/services/dnsmasq/patches/200-max-procs.patch
Do backup the original binary of dnsmasq before you test this one.
Index: dnsmasq-2.84/src/dnsmasq.c
===================================================================
--- dnsmasq-2.84.orig/src/dnsmasq.c
+++ dnsmasq-2.84/src/dnsmasq.c
@@ -1011,7 +1011,7 @@ int main (int argc, char **argv)
pid = getpid();
daemon->pipe_to_parent = -1;
- for (i = 0; i < MAX_PROCS; i++)
+ for (i = 0; i < daemon->max_procs; i++)
daemon->tcp_pipes[i] = -1;
#ifdef HAVE_INOTIFY
@@ -1459,7 +1459,7 @@ static void async_event(int pipe, time_t
break;
}
else
- for (i = 0 ; i < MAX_PROCS; i++)
+ for (i = 0 ; i < daemon->max_procs; i++)
if (daemon->tcp_pids[i] == p)
daemon->tcp_pids[i] = 0;
break;
@@ -1523,7 +1523,7 @@ static void async_event(int pipe, time_t
case EVENT_TERM:
/* Knock all our children on the head. */
- for (i = 0; i < MAX_PROCS; i++)
+ for (i = 0; i < daemon->max_procs; i++)
if (daemon->tcp_pids[i] != 0)
kill(daemon->tcp_pids[i], SIGALRM);
@@ -1702,7 +1702,7 @@ static int set_dns_listeners(time_t now)
/* death of a child goes through the select loop, so
we don't need to explicitly arrange to wake up here */
if (listener->tcpfd != -1)
- for (i = 0; i < MAX_PROCS; i++)
+ for (i = 0; i < daemon->max_procs; i++)
if (daemon->tcp_pids[i] == 0 && daemon->tcp_pipes[i] == -1)
{
poll_listen(listener->tcpfd, POLLIN);
@@ -1718,7 +1718,7 @@ static int set_dns_listeners(time_t now)
}
if (!option_bool(OPT_DEBUG))
- for (i = 0; i < MAX_PROCS; i++)
+ for (i = 0; i < daemon->max_procs; i++)
if (daemon->tcp_pipes[i] != -1)
poll_listen(daemon->tcp_pipes[i], POLLIN);
@@ -1750,7 +1750,7 @@ static void check_dns_listeners(time_t n
to free the process slot. Once the child process has gone, poll()
returns POLLHUP, not POLLIN, so have to check for both here. */
if (!option_bool(OPT_DEBUG))
- for (i = 0; i < MAX_PROCS; i++)
+ for (i = 0; i < daemon->max_procs; i++)
if (daemon->tcp_pipes[i] != -1 &&
poll_check(daemon->tcp_pipes[i], POLLIN | POLLHUP) &&
!cache_recv_insert(now, daemon->tcp_pipes[i]))
@@ -1879,7 +1879,7 @@ static void check_dns_listeners(time_t n
read_write(pipefd[0], &a, 1, 1);
#endif
- for (i = 0; i < MAX_PROCS; i++)
+ for (i = 0; i < daemon->max_procs; i++)
if (daemon->tcp_pids[i] == 0 && daemon->tcp_pipes[i] == -1)
{
daemon->tcp_pids[i] = p;
Index: dnsmasq-2.84/src/option.c
===================================================================
--- dnsmasq-2.84.orig/src/option.c
+++ dnsmasq-2.84/src/option.c
@@ -168,6 +168,7 @@ struct myoption {
#define LOPT_SINGLE_PORT 359
#define LOPT_SCRIPT_TIME 360
#define LOPT_PXE_VENDOR 361
+#define LOPT_MAX_PROCS 362
#ifdef HAVE_GETOPT_LONG
static const struct option opts[] =
@@ -341,6 +342,7 @@ static const struct myoption opts[] =
{ "dumpfile", 1, 0, LOPT_DUMPFILE },
{ "dumpmask", 1, 0, LOPT_DUMPMASK },
{ "dhcp-ignore-clid", 0, 0, LOPT_IGNORE_CLID },
+ { "max-procs", 1, 0, LOPT_MAX_PROCS },
{ NULL, 0, 0, 0 }
};
@@ -521,6 +523,7 @@ static struct {
{ LOPT_DUMPFILE, ARG_ONE, "<path>", gettext_noop("Path to debug packet dump file"), NULL },
{ LOPT_DUMPMASK, ARG_ONE, "<hex>", gettext_noop("Mask which packets to dump"), NULL },
{ LOPT_SCRIPT_TIME, OPT_LEASE_RENEW, NULL, gettext_noop("Call dhcp-script when lease expiry changes."), NULL },
+ { LOPT_MAX_PROCS, ARG_ONE, "<number>", gettext_noop("Specify maximum number of child process to fork."), NULL },
{ 0, 0, NULL, NULL, NULL }
};
@@ -4546,6 +4549,12 @@ err:
}
#endif
+ case LOPT_MAX_PROCS: /* --max-procs */
+ if (!atoi_check16(arg, &daemon->max_procs))
+ ret_err(gen_err);
+ if (daemon->max_procs > MAX_PROCS) daemon->max_procs = MAX_PROCS;
+ break;
+
default:
ret_err(_("unsupported option (check that dnsmasq was compiled with DHCP/TFTP/DNSSEC/DBus support)"));
@@ -5036,6 +5045,7 @@ void read_opts(int argc, char **argv, ch
daemon->soa_expiry = SOA_EXPIRY;
daemon->max_port = MAX_PORT;
daemon->min_port = MIN_PORT;
+ daemon->max_procs = MAX_PROCS;
#ifndef NO_ID
add_txt("version.bind", "dnsmasq-" VERSION, 0 );
Index: dnsmasq-2.84/src/dnsmasq.h
===================================================================
--- dnsmasq-2.84.orig/src/dnsmasq.h
+++ dnsmasq-2.84/src/dnsmasq.h
@@ -1169,6 +1169,9 @@ extern struct daemon {
/* file for packet dumps. */
int dumpfd;
#endif
+
+ /* maximum number of child processes to fork */
+ unsigned int max_procs;
} *daemon;
/* cache.c */
EDIT:
So here's a simple test to show you - use a script to launch 20 netcats to connect to tcp port 53. When running with the command line argument to cap the number of processes, dnsmasq has one process for the main dnsmasq instance and then a maximum additional number of processes equal to the specified value to process incoming tcp connections.
If the argument is not specified, then dnsmasq will spawn up to the maximum of 20 processes
root@openwrt:~# ps ax | grep netcat
26074 pts/0 S 0:00 netcat -t 127.0.0.1 53
26075 pts/0 S 0:00 netcat -t 127.0.0.1 53
26076 pts/0 S 0:00 netcat -t 127.0.0.1 53
26077 pts/0 S 0:00 netcat -t 127.0.0.1 53
26078 pts/0 S 0:00 netcat -t 127.0.0.1 53
26079 pts/0 S 0:00 netcat -t 127.0.0.1 53
26080 pts/0 S 0:00 netcat -t 127.0.0.1 53
26081 pts/0 S 0:00 netcat -t 127.0.0.1 53
26082 pts/0 S 0:00 netcat -t 127.0.0.1 53
26083 pts/0 S 0:00 netcat -t 127.0.0.1 53
26084 pts/0 S 0:00 netcat -t 127.0.0.1 53
26085 pts/0 S 0:00 netcat -t 127.0.0.1 53
26086 pts/0 S 0:00 netcat -t 127.0.0.1 53
26087 pts/0 S 0:00 netcat -t 127.0.0.1 53
26088 pts/0 S 0:00 netcat -t 127.0.0.1 53
26089 pts/0 S 0:00 netcat -t 127.0.0.1 53
26090 pts/0 S 0:00 netcat -t 127.0.0.1 53
26091 pts/0 S 0:00 netcat -t 127.0.0.1 53
26092 pts/0 S 0:00 netcat -t 127.0.0.1 53
26093 pts/0 S 0:00 netcat -t 127.0.0.1 53
26094 pts/0 S 0:00 netcat -t 127.0.0.1 53
26178 pts/0 S+ 0:00 grep netcat
root@openwrt:~# ps ax | grep dnsmasq
26026 pts/2 S+ 0:00 ./dnsmasq -C /var/etc/dnsmasq.conf.cfg01411c -k --max-procs=1
26095 pts/2 S+ 0:00 ./dnsmasq -C /var/etc/dnsmasq.conf.cfg01411c -k --max-procs=1
26212 pts/0 S+ 0:00 grep dnsmasq
root@openwrt:~#
3 Likes
First of all thanks for the netcat hint 
Before patching I was able to Oom dnsmasq just by opening new tcp connections to port 53 by netcat.
After your patch + max-procs=1 in /etc/dnsmasq.conf I was not able to Oom dnsmasq by opening tcp connections to port 53..
root@R7800:~# ps |grep netcat
4203 root 740 T netcat -t 127.0.0.1 53
4219 root 740 T netcat -t 127.0.0.1 53
4228 root 740 T netcat -t 127.0.0.1 53
4238 root 740 T netcat -t 127.0.0.1 53
4260 root 740 T netcat -t 127.0.0.1 53
4280 root 740 T netcat -t 127.0.0.1 53
4283 root 740 T netcat -t 127.0.0.1 53
4350 root 740 T netcat -t 127.0.0.1 53
4358 root 740 T netcat -t 127.0.0.1 53
4370 root 740 T netcat -t 127.0.0.1 53
4371 root 740 T netcat -t 127.0.0.1 53
4372 root 740 T netcat -t 127.0.0.1 53
4373 root 740 T netcat -t 127.0.0.1 53
4402 root 740 T netcat -t 127.0.0.1 53
4403 root 740 T netcat -t 127.0.0.1 53
4404 root 740 T netcat -t 127.0.0.1 53
4405 root 740 T netcat -t 127.0.0.1 53
4406 root 740 T netcat -t 127.0.0.1 53
4407 root 740 T netcat -t 127.0.0.1 53
4408 root 740 T netcat -t 127.0.0.1 53
4423 root 740 T netcat -t 127.0.0.1 53
4601 root 1080 R grep netcat
root@R7800:~# ps |grep dnsmasq
3988 dnsmasq 52448 S /usr/sbin/dnsmasq -C /var/etc/dnsmasq.conf.cfg01411c -k -x /var/run/dnsmasq/dnsmasq.cfg01411c.pid
4568 dnsmasq 52516 S /usr/sbin/dnsmasq -C /var/etc/dnsmasq.conf.cfg01411c -k -x /var/run/dnsmasq/dnsmasq.cfg01411c.pid
4621 root 1080 R grep dnsmasq
Then when using the Taxi App with max-procs=1 I was not able to get dnsmasq to Oom.
Once removed the max-procs=1 conf line and restarted the dnsmasq, I was pretty easily able to reproduce the dnsmasq Oom again.
Seems by default when opening Taxi App it's opening several tcp connections to port 53. It does not Oom every time but the percentage doing so is high.
Toggling max-procs=1 on and off the problem is repeatable.
So yes, at least in my Taxi App case (and when using https-dns-proxy) your patch fixed the dnsmasq Oom issue.
1 Like
Yeah, the default MAX_PROCS of 20 is really not suitable for a resource constrained embedded platform.
This patch should ideally be put into Openwrt, although there's understandable reluctance to patch upstream source unless really necessary.
Each tcp client can have up to 100 tcp requests, so I'm not sure that spawning up to 20 separate processes is really necessary except in the case of a very heavily loaded system
1 Like
Thanks. Will mark your patch as a solution.
Unless patch will be included to Openwrt It may though have a limited runtime as understand it's only relevant for current dnsmasq-2.84.
Well, that's the problem with a patch to upstream source. Every time the version gets bumped, there's a risk the patch won't apply or will need to be redone
Kind of depends on the device.
If we would assume we're going towards devices with more memory, the current max won't be an issue in the long run.
It's still a nice solution/hack you've created, and it should be implemented, here or up stream.
hat off!
At least I know the problem and able to overcome it (changing DoH to DoT and removing TCP:53 firewall forward) once patch does not work anymore.
I sent the patch to the dnsmasq author. Maybe he'll consider adding it...
1 Like
When I think about it, this is actually an exploitable denial of service attack on openwrt with a non-trivial number of platforms, although one with limited risk since it would require an internal user with query access to dnsmasq to exploit.
But, just making sure there are 20 netcats spawned all the time could effectively keep a targeted router out of memory...
Be interesting to know what happens to your router if you do something similar - keep having a netcat connect so that dnsmasq is always oom and whether it causes other things to break or not..
Theoretically, it's also exploitable by a malignant app that the user downloads...
#!/bin/sh
while true; do
instances=$(ps | grep netcat | wc -l)
[ "$instances" -ge 21 ] && continue
netcat -t 127.0.0.1 53 &
done
Thanks. Appreciate your effort trying to get this patch included to Openwrt.
Curious to know a couple of things about this if you could maybe dig in a bit...
- Exactly how many times does dnsmasq have to fork before the router is oom?
- Could you post your
/etc/dnsmasq.conf - With only one dnsmasq process running, can you post a screen shot of your memory usage (used, buffers, cache)
- Then the same thing when dnsmasq cause oom errors...
- What are your exact router specs? Precise make and model...
I just noticed you changed your dnsmasq cache size in /etc/dnsmasq.conf. You should try removing this option cachesize '1000' line (and removing the --max-procs= value) and see if the problem still occurs.
Router is Netgear R7800:
root@R7800:~# ubus call system board
{
"kernel": "5.4.106",
"hostname": "R7800",
"system": "ARMv7 Processor rev 0 (v7l)",
"model": "Netgear Nighthawk X4S R7800",
"board_name": "netgear,r7800",
"release": {
"distribution": "OpenWrt",
"version": "SNAPSHOT",
"revision": "r16345-d71424a085",
"target": "ipq806x/generic",
"description": "OpenWrt SNAPSHOT r16345-d71424a085"
}
}
/etc/dnsmasq.conf (max-procs commented out for below testing)
root@R7800:~# cat /etc/dnsmasq.conf
# Change the following lines if you want dnsmasq to serve SRV
# records.
# You may add multiple srv-host lines.
# The fields are <name>,<target>,<port>,<priority>,<weight>
# A SRV record sending LDAP for the example.com domain to
# ldapserver.example.com port 289
#srv-host=_ldap._tcp.example.com,ldapserver.example.com,389
# Two SRV records for LDAP, each with different priorities
#srv-host=_ldap._tcp.example.com,ldapserver.example.com,389,1
#srv-host=_ldap._tcp.example.com,ldapserver.example.com,389,2
# A SRV record indicating that there is no LDAP server for the domain
# example.com
#srv-host=_ldap._tcp.example.com
# The following line shows how to make dnsmasq serve an arbitrary PTR
# record. This is useful for DNS-SD.
# The fields are <name>,<target>
#ptr-record=_http._tcp.dns-sd-services,"New Employee Page._http._tcp.dns-sd-services"
# Change the following lines to enable dnsmasq to serve TXT records.
# These are used for things like SPF and zeroconf.
# The fields are <name>,<text>,<text>...
#Example SPF.
#txt-record=example.com,"v=spf1 a -all"
#Example zeroconf
#txt-record=_http._tcp.example.com,name=value,paper=A4
# Provide an alias for a "local" DNS name. Note that this _only_ works
# for targets which are names from DHCP or /etc/hosts. Give host
# "bert" another name, bertrand
# The fields are <cname>,<target>
#cname=bertand,bert
#max-procs=1
root@R7800:~#
Below memory usage after commenting out option cachesize '1000' and reboot:
root@R7800:~# free -m
total used free shared buff/cache available
Mem: 444176 133436 257800 12472 52940 253460
Swap: 0 0 0
Notes:
- I use adblock and have +300k blocked domains
Tue Mar 30 20:22:53 2021 user.info adblock-4.1.0[1278]: adblock instance started ::: action: start, priority: 0, pid: 1278
Tue Mar 30 20:24:15 2021 user.info adblock-4.1.0[1278]: blocklist with overall 309334 blocked domains loaded successfully (Netgear Nighthawk X4S R7800, OpenWrt SNAPSHOT r16345-d71424a085)
- Slighly cut the memory to get pstore/ramoops activated
[ 0.000000] Kernel command line: mem=0x1C000000 ramoops.mem_address=0x5F000000 ramoops.mem_size=0x2C000 ramoops.record_size=0x4000
[ 0.018995] ramoops: using module parameters
[ 0.019360] pstore: Registered ramoops as persistent store backend
[ 0.019378] ramoops: using 0x2c000@0x5f000000, ecc: 0
For below testing of dnsmasq oom I used netcat as when using Taxi App oo-reaper clears all the extra dnsmasq processes and memory consumption returns normal.
Mem after 1st netcat -t 127.0.0.1 53 &
root@R7800:~# free -m
total used free shared buff/cache available
Mem: 444176 185020 206048 12472 53108 201792
Swap: 0 0 0
Mem after 2nd netcat -t 127.0.0.1 53 &
root@R7800:~# free -m
total used free shared buff/cache available
Mem: 444176 232116 158928 12472 53132 154684
Swap: 0 0 0
Mem after 3rd netcat -t 127.0.0.1 53 &
root@R7800:~# free -m
total used free shared buff/cache available
Mem: 444176 283340 107692 12472 53144 103456
Swap: 0 0 0
Mem after 4th netcat -t 127.0.0.1 53 &
root@R7800:~# free -m
total used free shared buff/cache available
Mem: 444176 338756 52232 12472 53188 48016
Swap: 0 0 0
Mem after 5th netcat -t 127.0.0.1 53 &
root@R7800:~# free -m
total used free shared buff/cache available
Mem: 444176 386996 26696 12472 30484 11088
Swap: 0 0 0
Mem after 6th netcat -t 127.0.0.1 53 & --> dnsmasq oom
root@R7800:~# free -m
total used free shared buff/cache available
Mem: 444176 389360 29004 12472 25812 11100
Swap: 0 0 0
syslog - dnsmasq oom
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.820556] dnsmasq invoked oom-killer: gfp_mask=0x100cca(GFP_HIGHUSER_MOVABLE), order=0, oom_score_adj=0
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.820590] CPU: 0 PID: 9121 Comm: dnsmasq Not tainted 5.4.106 #0
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.829094] Hardware name: Generic DT based system
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.835182] [<c0311068>] (unwind_backtrace) from [<c030c4e0>] (show_stack+0x14/0x20)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.839867] [<c030c4e0>] (show_stack) from [<c0923098>] (dump_stack+0x94/0xa8)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.847768] [<c0923098>] (dump_stack) from [<c0422338>] (dump_header+0x54/0x1a8)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.854794] [<c0422338>] (dump_header) from [<c0422bb4>] (oom_kill_process+0x190/0x194)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.862347] [<c0422bb4>] (oom_kill_process) from [<c04235c8>] (out_of_memory+0x268/0x324)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.870076] [<c04235c8>] (out_of_memory) from [<c0467dd8>] (__alloc_pages_nodemask+0xb9c/0x1260)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.878410] [<c0467dd8>] (__alloc_pages_nodemask) from [<c044e8f4>] (wp_page_copy+0x64/0x77c)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.887262] [<c044e8f4>] (wp_page_copy) from [<c04513a8>] (do_wp_page+0xb0/0x5b0)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.895678] [<c04513a8>] (do_wp_page) from [<c04529a0>] (handle_mm_fault+0x64c/0xb6c)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.903147] [<c04529a0>] (handle_mm_fault) from [<c0311fd4>] (do_page_fault+0x124/0x2c4)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.910960] [<c0311fd4>] (do_page_fault) from [<c0312328>] (do_DataAbort+0x48/0xd4)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.919117] [<c0312328>] (do_DataAbort) from [<c0301ddc>] (__dabt_usr+0x3c/0x40)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.926492] Exception stack(0xda22dfb0 to 0xda22dff8)
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.934132] dfa0: 00000000 00000000 04145f10 ffffffff
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.939089] dfc0: 00000000 004b2f58 00000026 00000000 004b2f58 004b2fa0 004b2f3c 05425990
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.947245] dfe0: bef34b20 bef34b60 00482f84 0048311c 20000010 ffffffff
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.955529] Mem-Info:
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.961836] active_anon:83316 inactive_anon:770 isolated_anon:0
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.961836] active_file:14 inactive_file:50 isolated_file:1
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.961836] unevictable:0 dirty:1 writeback:3 unstable:0
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.961836] slab_reclaimable:1994 slab_unreclaimable:3315
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.961836] mapped:3 shmem:3118 pagetables:336 bounce:0
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.961836] free:4015 free_pcp:33 free_cma:0
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.974227] Node 0 active_anon:333264kB inactive_anon:3080kB active_file:92kB inactive_file:200kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:12kB dirty:4kB writeback:8kB shmem:12472kB writeback_tmp:0kB unstable:0kB all_unreclaimable? yes
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1760.996533] Normal free:16060kB min:16384kB low:20480kB high:24576kB active_anon:332796kB inactive_anon:3080kB active_file:40kB inactive_file:284kB unevictable:0kB writepending:12kB present:458752kB managed:444176kB mlocked:0kB kernel_stack:856kB pagetables:1344kB bounce:0kB free_pcp:132kB local_pcp:0kB free_cma:0kB
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1761.024640] lowmem_reserve[]: 0 0 0
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1761.046894] Normal: 165*4kB (UE) 119*8kB (UME) 43*16kB (UE) 12*32kB (UE) 17*64kB (UE) 19*128kB (UME) 5*256kB (UE) 1*512kB (M) 0*1024kB 2*2048kB (UE) 1*4096kB (M) = 16188kB
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1761.050128] 3199 total pagecache pages
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1761.065440] 0 pages in swap cache
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1761.069211] Swap cache stats: add 0, delete 0, find 0/0
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1761.072579] Free swap = 0kB
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1761.077674] Total swap = 0kB
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1761.080738] 114688 pages RAM
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1761.083671] 0 pages HighMem/MovableOnly
Tue Mar 30 20:50:39 2021 kern.warn kernel: [ 1761.086466] 3644 pages reserved
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.090041] Tasks state (memory values in pages):
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.093168] [ pid ] uid tgid total_vm rss pgtables_bytes swapents oom_score_adj name
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.098087] [ 190] 81 190 260 23 10240 0 0 ubusd
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.106606] [ 191] 0 191 176 10 6144 0 0 askfirst
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.114853] [ 235] 0 235 204 12 6144 0 0 urngd
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.123283] [ 614] 514 614 267 42 10240 0 0 logd
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.131412] [ 615] 0 615 293 23 8192 0 0 logread
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.139564] [ 667] 0 667 500 64 12288 0 0 rpcd
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.147655] [ 736] 323 736 252 33 8192 0 0 chronyd
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.155996] [ 954] 0 954 215 11 6144 0 0 dropbear
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.164056] [ 1052] 0 1052 1027 68 12288 0 0 hostapd
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.172675] [ 1053] 0 1053 1003 51 12288 0 0 wpa_supplicant
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.180811] [ 1115] 0 1115 393 37 8192 0 0 netifd
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.189829] [ 1311] 0 1311 211 14 6144 0 0 odhcp6c
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.198076] [ 1336] 0 1336 270 10 8192 0 0 udhcpc
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.206324] [ 1462] 0 1462 315 31 6144 0 0 odhcpd
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.214665] [ 1626] 0 1626 271 10 8192 0 0 crond
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.222848] [ 1813] 0 1813 1016 152 12288 0 0 uhttpd
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.231161] [ 2000] 0 2000 1045 160 10240 0 0 collectd
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.239313] [ 2089] 65534 2089 1043 317 12288 0 0 https-dns-proxy
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.247904] [ 2090] 65534 2090 1080 353 14336 0 0 https-dns-proxy
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.256683] [ 4161] 453 4161 13047 12443 61440 0 0 dnsmasq
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.265711] [ 4536] 0 4536 229 22 8192 0 0 dropbear
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.274052] [ 4555] 0 4555 272 13 8192 0 0 ash
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.282659] [ 8868] 0 8868 185 15 8192 0 0 netcat
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.290454] [ 8869] 453 8869 13064 12444 61440 0 0 dnsmasq
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.298764] [ 8883] 0 8883 185 15 8192 0 0 netcat
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.307011] [ 8884] 453 8884 13064 12444 61440 0 0 dnsmasq
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.315352] [ 8890] 0 8890 185 15 8192 0 0 netcat
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.323600] [ 8891] 453 8891 13064 12444 61440 0 0 dnsmasq
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.331878] [ 8900] 0 8900 185 15 8192 0 0 netcat
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.340187] [ 8901] 453 8901 13064 12444 61440 0 0 dnsmasq
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.348528] [ 9046] 0 9046 185 15 10240 0 0 netcat
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.356776] [ 9047] 453 9047 13064 12444 61440 0 0 dnsmasq
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.365087] [ 9120] 0 9120 185 15 10240 0 0 netcat
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.373282] [ 9121] 453 9121 13047 12442 61440 0 0 dnsmasq
Tue Mar 30 20:50:39 2021 kern.info kernel: [ 1761.381671] oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0,global_oom,task_memcg=/,task=dnsmasq,pid=9047,uid=453
Tue Mar 30 20:50:39 2021 kern.err kernel: [ 1761.389935] Out of memory: Killed process 9047 (dnsmasq) total-vm:52256kB, anon-rss:49776kB, file-rss:0kB, shmem-rss:0kB, UID:453 pgtables:60kB oom_score_adj:0