Ok, I did some debugging and this looks really weird. First, trying to run NetworkManager --debug manually:
<info> [1538138381.5570] audit: op="connection-activate" uuid="1a43441b-6b26-4e0c-8343-976afcf790fd" name="DataStax" pid=3717 uid=1001 result="success" <info> [1538138381.5755] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",0]: Started the VPN service, PID 8148 <info> [1538138381.5973] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",0]: Saw the service appear; activating connection <info> [1538138381.6059] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",0]: VPN plugin: state changed: starting (3) <info> [1538138381.6060] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",0]: VPN connection: (ConnectInteractive) reply received <info> [1538138381.6485] manager: (tun0): new Tun device (/org/freedesktop/NetworkManager/Devices/6) <info> [1538138381.6586] devices added (path: /sys/devices/virtual/net/tun0, iface: tun0) <info> [1538138381.6586] device added (path: /sys/devices/virtual/net/tun0, iface: tun0): no ifupdown configuration found. <info> [1538138382.5173] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",0]: VPN connection: (IP4 Config Get) reply received from old-style plugin <info> [1538138382.5177] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: VPN Gateway: 12.111.84.106 <info> [1538138382.5178] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: Tunnel Device: "tun0" <info> [1538138382.5178] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: IPv4 configuration: <info> [1538138382.5178] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: Internal Address: 10.150.1.247 <info> [1538138382.5178] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: Internal Prefix: 32 <info> [1538138382.5178] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: Internal Point-to-Point Address: 10.150.1.247 <info> [1538138382.5178] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: Static Route: 0.0.0.0/0 Next Hop: 0.0.0.0 <info> [1538138382.5178] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: Static Route: 10.150.1.247/32 Next Hop: 0.0.0.0 <info> [1538138382.5179] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: Internal DNS: 10.200.1.10 <info> [1538138382.5179] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: Internal DNS: 10.200.1.11 <info> [1538138382.5179] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: DNS Domain: 'datastax.lan' <info> [1538138382.5179] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: Data: No IPv6 configuration <info> [1538138382.5179] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: VPN plugin: state changed: started (4) <info> [1538138382.5447] vpn-connection[0x55c2f915e0b0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",7:(tun0)]: VPN connection: (IP Config Get) complete <info> [1538138382.5451] device (tun0): state change: unmanaged -> unavailable (reason 'connection-assumed', sys-iface-state: 'external') <info> [1538138382.5796] keyfile: add connection in-memory (b59f240b-d74e-4c9f-a5c7-219cdff8374d,"tun0") <info> [1538138382.5809] device (tun0): state change: unavailable -> disconnected (reason 'connection-assumed', sys-iface-state: 'external') <info> [1538138382.5819] device (tun0): Activation: starting connection 'tun0' (b59f240b-d74e-4c9f-a5c7-219cdff8374d) <info> [1538138382.5824] device (tun0): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'external') <info> [1538138382.5829] device (tun0): state change: prepare -> config (reason 'none', sys-iface-state: 'external') <info> [1538138382.5833] device (tun0): state change: config -> ip-config (reason 'none', sys-iface-state: 'external') <info> [1538138382.5840] device (tun0): state change: ip-config -> ip-check (reason 'none', sys-iface-state: 'external') <info> [1538138382.5852] device (tun0): state change: ip-check -> secondaries (reason 'none', sys-iface-state: 'external') <info> [1538138382.5854] device (tun0): state change: secondaries -> activated (reason 'none', sys-iface-state: 'external') <info> [1538138382.5913] device (tun0): Activation: successful, device activated. Naruszenie ochrony pamięci /// <<<< SIGSEGV (crash) Then trying to do the same under valgrind: <info> [1538138423.6684] audit: op="connection-activate" uuid="1a43441b-6b26-4e0c-8343-976afcf790fd" name="DataStax" pid=3717 uid=1001 result="success" ==9083== ==9083== HEAP SUMMARY: ==9083== in use at exit: 1,070,170 bytes in 14,200 blocks ==9083== total heap usage: 357,423 allocs, 343,223 frees, 22,893,758 bytes allocated ==9083== ==9083== LEAK SUMMARY: ==9083== definitely lost: 5,168 bytes in 34 blocks ==9083== indirectly lost: 3,595 bytes in 41 blocks ==9083== possibly lost: 2,466 bytes in 30 blocks ==9083== still reachable: 918,773 bytes in 13,004 blocks ==9083== of which reachable via heuristic: ==9083== length64 : 2,192 bytes in 44 blocks ==9083== newarray : 1,856 bytes in 36 blocks ==9083== suppressed: 0 bytes in 0 blocks ==9083== Rerun with --leak-check=full to see details of leaked memory ==9083== ==9083== For counts of detected and suppressed errors, rerun with: -v ==9083== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0) <info> [1538138423.7732] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",0]: Started the VPN service, PID 9084 <info> [1538138423.7754] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",0]: Saw the service appear; activating connection <info> [1538138423.8811] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",0]: VPN plugin: state changed: starting (3) <info> [1538138423.8852] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",0]: VPN connection: (ConnectInteractive) reply received <info> [1538138423.9018] manager: (tun0): new Tun device (/org/freedesktop/NetworkManager/Devices/6) <info> [1538138423.9322] devices added (path: /sys/devices/virtual/net/tun0, iface: tun0) <info> [1538138423.9328] device added (path: /sys/devices/virtual/net/tun0, iface: tun0): no ifupdown configuration found. <info> [1538138425.5369] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",0]: VPN connection: (IP4 Config Get) reply received from old-style plugin <info> [1538138425.5557] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: VPN Gateway: 12.111.84.106 <info> [1538138425.5568] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: Tunnel Device: "tun0" <info> [1538138425.5584] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: IPv4 configuration: <info> [1538138425.5594] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: Internal Address: 10.150.1.248 <info> [1538138425.5601] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: Internal Prefix: 32 <info> [1538138425.5609] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: Internal Point-to-Point Address: 10.150.1.248 <info> [1538138425.5620] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: Static Route: 0.0.0.0/0 Next Hop: 0.0.0.0 <info> [1538138425.5625] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: Static Route: 10.150.1.248/32 Next Hop: 0.0.0.0 <info> [1538138425.5634] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: Internal DNS: 10.200.1.10 <info> [1538138425.5640] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: Internal DNS: 10.200.1.11 <info> [1538138425.5648] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: DNS Domain: 'datastax.lan' <info> [1538138425.5657] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: Data: No IPv6 configuration <info> [1538138425.5678] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: VPN plugin: state changed: started (4) <info> [1538138425.6325] vpn-connection[0xa1b47a0,1a43441b-6b26-4e0c-8343-976afcf790fd,"DataStax",8:(tun0)]: VPN connection: (IP Config Get) complete <info> [1538138425.6388] device (tun0): state change: unmanaged -> unavailable (reason 'connection-assumed', sys-iface-state: 'external') <info> [1538138425.7763] keyfile: add connection in-memory (536feec9-98d9-443b-aebb-084529bef1a6,"tun0") <info> [1538138425.7987] device (tun0): state change: unavailable -> disconnected (reason 'connection-assumed', sys-iface-state: 'external') <info> [1538138425.8178] device (tun0): Activation: starting connection 'tun0' (536feec9-98d9-443b-aebb-084529bef1a6) <info> [1538138425.8198] device (tun0): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'external') <info> [1538138425.8269] device (tun0): state change: prepare -> config (reason 'none', sys-iface-state: 'external') <info> [1538138425.8323] device (tun0): state change: config -> ip-config (reason 'none', sys-iface-state: 'external') <info> [1538138425.8375] device (tun0): state change: ip-config -> ip-check (reason 'none', sys-iface-state: 'external') <info> [1538138425.8518] device (tun0): state change: ip-check -> secondaries (reason 'none', sys-iface-state: 'external') <info> [1538138425.8557] device (tun0): state change: secondaries -> activated (reason 'none', sys-iface-state: 'external') <info> [1538138425.8957] device (tun0): Activation: successful, device activated. // <<--- the last message // ... (wait) // ... (wait) // ... (wait) // ???? no further messages, no crash, it works like a charm -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1794966 Title: Network manager crashes and restarts 2 seconds after establishing a VPN connection To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1794966/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
