Re: [libvirt-php] libvirt_domain_interface_addresses causing segfault
I think I found the problem and it seems to affect only Windows guests.
I'm not sure about the cause tough.
Possible causes:
1- Network interface names containing white spaces.
2- One of the interfaces not reporting a MAC address.
As an example here is the output of the equivalent virsh command for a
Windows guest:
Name MAC address Protocol Address
-------------------------------------------------------------------------------
Ethernet 2 52:54:00:99:b5:62 ipv6 fe80::71fd:2467:8755:cb0b%13/64
Ethernet 2 52:54:00:99:b5:62 ipv4 192.168.0.77/26
Loopback Pseudo-Interface 1 ipv6 ::1/128
Loopback Pseudo-Interface 1 ipv4 127.0.0.1/8
isatap.{974B556C-9BAF-4A84-A1B1-9D1FDABEC29B} 00:00:00:00:00:00 ipv6
fe80::5efe:192.168.7.21%12/128
Please note the name containing white spaces: "Ethernet 2", "Loopback
Pseudo-Interface 1". And also interface "Loopback Pseudo-Interface 1"
not reporting a MAC address.
Hope this additional information helps.
Thanks.
Fernando
On mié, abr 15, 2020 at 11:41 PM, Fernando Casas Schössow
<casasfernando(a)outlook.com> wrote:
Hi,
While executing libvirt_domain_interface_addresses() with the
qemu-agent running in the guest as the source, the function causes
PHP to segfault. If I change the source to either dhcp or arp, the
function executes correctly.
Example:
$netdetails = libvirt_domain_interface_addresses($vmres, 0); <--
executes correctly (dhcp source)
$netdetails = libvirt_domain_interface_addresses($vmres, 1); <--
segfault (qemu agent source)
$netdetails = libvirt_domain_interface_addresses($vmres, 2); <--
executes correctly (arp source)
I tested the equivalent function using virsh against the same host
and it executes correctly with any source.
I have a php-cgi core file that I can share if that may help on
finding the problem.
gdb output:
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Reading symbols from /usr/bin/php-cgi...
(No debugging symbols found in /usr/bin/php-cgi)
[New LWP 2594]
[Thread debugging using libthread_db enabled]
Using host libthread_db library
"/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `php-cgi index.php'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 __strlen_sse2 () at ../sysdeps/x86_64/multiarch/../strlen.S:85
85 ../sysdeps/x86_64/multiarch/../strlen.S: No such file or directory.
(gdb) bt
#0 __strlen_sse2 () at ../sysdeps/x86_64/multiarch/../strlen.S:85
#1 0x000055c6a4ceacd2 in add_assoc_string_ex ()
#2 0x00007f4d36175253 in ?? () from
/usr/lib/php/20180731/libvirt-php.so
#3 0x000055c6a4d6b477 in execute_ex ()
#4 0x000055c6a4d705c7 in zend_execute ()
#5 0x000055c6a4ce8ed4 in zend_execute_scripts ()
#6 0x000055c6a4c8be38 in php_execute_script ()
#7 0x000055c6a4b53da8 in ?? ()
#8 0x00007f4d39efce0b in __libc_start_main (main=0x55c6a4b51cf0,
argc=2, argv=0x7fff35718588, init=<optimized out>, fini=<optimized
out>,
rtld_fini=<optimized out>, stack_end=0x7fff35718578) at
../csu/libc-start.c:308
#9 0x000055c6a4b544ca in _start ()
System information:
OS: Debian Bullseye
PHP version (fast cgi): 7.3.15
Libvirt PHP version: 0.5.5
Libvirt version: 6.0.0
KVM host libvirt version: 5.9.0
If you need any other information please let me know.
Thanks.
Fernando