Hi.
Try to assemble uClibc and bird with debug symbols, and try to analyze
core dump.
Also it'll be good to run bird (better- to use debug version) in
valgrind - it'll show all suspicious cases (like access across array
borders, use of uninitialized variables and so on).
On 24.10.2018 18:05, Alexander Velkov wrote:
Hello bird-team,
I have a bird v1.6.4. configuration that works fine.
A certain set of actions leads to a segfault and a crash of the bird
binary.
I have configured and built bird 1.6.4. with IPv6 support that runs on
a box with a i686 linux with kernel v4.14.75. My bird configuration:
### bird6.conf:
protocol device {
scan time 10;
}
protocol direct C_main {
interface "*";
preference 255;
check link;
}
protocol kernel K_main {
preference 255;
scan time 20;
export all;
learn;
}
include "*.conff";
### ospfv3.conff in the same directory:
debug protocols all;
log syslog { info, remote, warning, error, auth, fatal, bug };
protocol ospf O_main {
preference 145;
instance id 0;
area 172.16.0.0 {
interface "vti0" {
dead 120;
hello 30;
cost 1;
priority 1;
type pointopoint;
neighbors {
fe80::e68:3ff:fe26:5130;
};
};
interface "eth1" {
dead 40;
hello 10;
cost 1;
priority 1;
type broadcast;
stub yes;
};
};
import filter {
accept;
};
export filter {
reject;
};
}
### The following actions lead to a crash of bird6:
EEPD[~]# /sbin/bird6 -P /var/run/bird6.pid -c /var/etc/bird6/bird6.conf
Oct 24 14:23:08 EEPD info bird6 [ 4684]: Started
EEPD[~]# ps | grep bird6
4930 root 1500 S /sbin/bird6 -P /var/run/bird6.pid -c
/var/etc/bird6/bird6.conf
4932 root 1284 S grep bird6
EEPD[~]#
EEPD[~]# ip -6 link add vti0 type vti6 local fd00::38 remote fd00::1b
ikey 2 okey 2;
EEPD[~]# ip -6 link set vti0 up;
EEPD[~]# ifconfig vti0 mtu 1422
Oct 24 14:23:17 EEPD err bird6 [ 4684]: KIF: Received address
message for unknown interface 33
Oct 24 14:23:20 EEPD err bird6 [ 4684]: O_main: Socket error on
vti0: Invalid argument
Oct 24 14:23:20 EEPD info kernel: [ 4684]: segfault at 58e ip
b7eed103 sp bf9acad8 error 4 in libuClibc-1.0.30.so
<http://libuClibc-1.0.30.so>[b7ebd000+72000]
EEPD[~]#
EEPD[~]# ps | grep bird6
4988 root 1284 S grep bird6
EEPD[~]#
### Further testing
- bird does NOT crash if the contents of bird6.conf and ospfv3.conf
are placed in a single file without inclusion.
- bird does NOT crash if the call 'ifconfig vti0 mtu 1422' is executed
before 'ip -6 link set vti0 up'.
Hope this information helps.
Best Regards
Alex
