dhcpcd-discuss

Hi

On 04/06/2018 22:05, LE GARREC Vincent wrote:
> I found in my dump folder a dump of dhcpcd (7.0.4). I have no idea why 
> or what action made dhcpcd crash.
>
> I'm using Internet from USB shared by my Android phone.
>
> The backtrace is:
>
> #0  0x0000555ca80563ce in if_address (cmd=21 '\025', 
> addr=0x555ca82cef80) at if-linux.c:1459

This is nlm.ifa.ifa_index = addr->iface->index ... which means that the 
address lost or has an invalid interface pointer.

> #1  0x0000555ca8062905 in ipv4_deladdr (addr=0x555ca82cef80, keeparp=1) 
> at ipv4.c:472
> #2  0x0000555ca8066175 in ipv4ll_freedrop (ifp=0x555ca82b5160, drop=1) 
> at ipv4ll.c:448
> #3  0x0000555ca803abec in dhcpcd_drop (ifp=0x555ca82b5160, stop=0) at 
> dhcpcd.c:369
> #4  0x0000555ca803b9db in dhcpcd_handlecarrier (ctx=0x7ffc1ffba240, 
> carrier=-1, flags=4098, ifname=0x7ffc1ffb9fe0 "enp0s26u1u2") at dhcpcd.c:728
> #5  0x0000555ca8054b36 in link_netlink (ctx=0x7ffc1ffba240, 
> ifp=0x555ca82b5160, nlm=0x555ca82b1740) at if-linux.c:798
> #6  0x0000555ca8053d3c in get_netlink (ctx=0x7ffc1ffba240, 
> iov=0x7ffc1ffba338, ifp=0x0, fd=7, flags=64, callback=0x555ca805478f 
> <link_netlink>)
>      at if-linux.c:402
> #7  0x0000555ca8054b92 in if_handlelink (ctx=0x7ffc1ffba240) at 
> if-linux.c:808
> #8  0x0000555ca803c7b7 in dhcpcd_handlelink (arg=0x7ffc1ffba240) at 
> dhcpcd.c:1039
> #9  0x0000555ca8040eea in eloop_start (eloop=0x555ca82a4dc0, 
> signals=0x7ffc1ffba348) at eloop.c:978
> #10 0x0000555ca803f20e in main (argc=2, argv=0x7ffc1ffba708) at 
> dhcpcd.c:1998
>
> What I found is :
>    - in frame 0, "addr->iface" is a "random" number : 0x735f7265676e6966.
>    - in frame 4, "addr->iface" is "((struct ipv4ll_state 
> *)(ifp)->if_data[2])->addr->iface"
>    - "ifname" is "enp0s26u1u2" and "ifp->options->options" =
> 0x44F8029841C5C09

addr->iface in frame 0 should match ifp in frame 2.

> dhcpcd --version
> dhcpcd 7.0.4
> Copyright (c) 2006-2018 Roy Marples
> Compiled in features: INET ARP ARPing IPv4LL INET6 DHCPv6 AUTH
>
> cat /etc/dhcpcd.conf
> hostname
> duid
> persistent
> option rapid_commit
> option domain_name_servers, domain_name, domain_search, host_name
> option classless_static_routes
> option interface_mtu
> require dhcp_server_identifier
> slaac private
>
> I can say that my connection with the device is not stable because of 
> networkmanager. For further information, see: https://bugs.gentoo.org/622082
>
> If you need for information, I still have the dump.

The dump AND the dhcpcd binary would be nice to have please.

Roy