Comment 74 for bug 1815101

We are seeing SIGSEGV related to this in Bionic. lp1815101-0006-network-make-KeepConfiguration-static-drop-DHCP-addr.patch is missing network checks in link_drop_foreign_config

Would it be possible to incorporate this patch from upstream to prevent this? https://github.com/systemd/systemd/commit/b1b0b42e48303134731e017a108c6c334ef5f4c8

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Core was generated by `/lib/systemd/systemd-networkd'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x0000555962aa1c34 in link_drop_foreign_config (link=link@entry=0x555963583f30) at ../src/network/networkd-link.c:2741
2741 ../src/network/networkd-link.c: No such file or directory.
(gdb) bt
#0 0x0000555962aa1c34 in link_drop_foreign_config (link=link@entry=0x555963583f30) at ../src/network/networkd-link.c:2741
#1 0x0000555962aa233d in link_carrier_lost.lto_priv.328 (link=<optimized out>, link=<optimized out>) at ../src/network/networkd-link.c:3462
#2 0x0000555962a8e9b2 in link_update (m=0x5559635702c0, link=<optimized out>) at ../src/network/networkd-link.c:3698
#3 manager_rtnl_process_link (rtnl=<optimized out>, message=0x5559635702c0, userdata=<optimized out>) at ../src/network/networkd-manager.c:713
#4 0x0000555962a48a16 in process_match (m=0x5559635702c0, rtnl=0x55596355d990) at ../src/libsystemd/sd-netlink/sd-netlink.c:388
#5 process_running (ret=0x0, rtnl=0x55596355d990) at ../src/libsystemd/sd-netlink/sd-netlink.c:418
#6 sd_netlink_process (rtnl=0x55596355d990, ret=ret@entry=0x0) at ../src/libsystemd/sd-netlink/sd-netlink.c:452
#7 0x0000555962a48cb3 in time_callback (s=<optimized out>, usec=<optimized out>, userdata=<optimized out>) at ../src/libsystemd/sd-netlink/sd-netlink.c:759
#8 0x0000555962a4dbae in source_dispatch (s=s@entry=0x55596355dce0) at ../src/libsystemd/sd-event/sd-event.c:2311
#9 0x0000555962a4de2a in sd_event_dispatch (e=<optimized out>, e@entry=0x55596355bf70) at ../src/libsystemd/sd-event/sd-event.c:2663
#10 0x0000555962a4dfb9 in sd_event_run (e=<optimized out>, e@entry=0x55596355bf70, timeout=timeout@entry=18446744073709551615) at ../src/libsystemd/sd-event/sd-event.c:2723
#11 0x0000555962a4e1fb in sd_event_loop (e=<optimized out>) at ../src/libsystemd/sd-event/sd-event.c:2744
#12 0x0000555962a223d6 in main (argc=<optimized out>, argv=<optimized out>) at ../src/network/networkd.c:158

(gdb) p link->network
$2 = (struct Network *) 0x0