[Xorp-hackers] xorp_fea crashes when interface is removed from OS at in-opportune time.

[Ben Greear]

Ben Greear wrote:
> Seems xorp is very fragile when it comes to adding/deleting
> interfaces.  I think a lot of these errors should just be warnings,
> not asserts.

And another related to the first:

diff -u -r1.15 fibconfig_entry_set_netlink_socket.cc
--- fibconfig_entry_set_netlink_socket.cc       12 Oct 2007 07:53:47 -0000      1.15
+++ fibconfig_entry_set_netlink_socket.cc       20 Oct 2007 03:10:55 -0000
@@ -256,7 +256,11 @@
                 break;
             const IfTree& iftree = fibconfig().iftree();
             const IfTreeInterface* ifp = iftree.find_interface(fte.ifname());
-           XLOG_ASSERT(ifp != NULL);
+           if (!ifp) {
+               XLOG_ERROR("Could not find interface: %s, maybe it was just deleted?\n",
+                          fte.ifname().c_str());
+               return XORP_ERROR;
+           }

             if (ifp->discard()) {
                 rtmsg->rtm_type = RTN_BLACKHOLE;


(gdb) bt
#0  0xffffe410 in __kernel_vsyscall ()
#1  0x49d42ee9 in raise () from /lib/libc.so.6
#2  0x49d444f1 in abort () from /lib/libc.so.6
#3  0x08287669 in xlog_fatal (module_name=Could not find the frame base for "xlog_fatal".
) at xlog.c:435
#4  0x081069a8 in FibConfigEntrySetNetlinkSocket::add_entry (this=0x842ee50, fte=@0x77d9d2d4)
     at fibconfig_entry_set_netlink_socket.cc:259
#5  0x0810707d in FibConfigEntrySetNetlinkSocket::add_entry4 (this=0x842ee50, fte=@0x8473ee0)
     at fibconfig_entry_set_netlink_socket.cc:100
#6  0x0807eee4 in FibConfig::add_entry4 (this=0x77da993c, fte=@0x8473ee0) at fibconfig.cc:1077
#7  0x0805e025 in FibAddEntry4::dispatch (this=0x8473ed8) at fibconfig_transaction.hh:112
#8  0x082b2387 in TransactionManager::Transaction::commit (this=0x8442eec) at transaction.cc:59
#9  0x082b0e76 in TransactionManager::commit (this=0x837e910, tid=24373279) at transaction.cc:201
#10 0x08080684 in FibConfig::commit_transaction (this=0x77da993c, tid=24373279, error_msg=@0x77d9d480)
     at fibconfig.cc:135
#11 0x080553ad in XrlFeaTarget::redist_transaction4_0_1_commit_transaction (this=0x77daa470, tid=@0x84701bc)
     at xrl_fea_target.cc:2351
#12 0x0817db00 in XrlFeaTargetBase::handle_redist_transaction4_0_1_commit_transaction (this=0x77daa470,
     xa_inputs=@0x77da14fc) at fea_base.cc:3230
#13 0x081a894f in XorpMemberCallback2B0<XrlCmdError const, XrlFeaTargetBase, XrlArgs const&, XrlArgs*>::dispatch (
     this=0x8418148, a1=@0x77da14fc, a2=0x77da14e0) at ../../libxorp/callback_nodebug.hh:4615
#14 0x08256f25 in XrlCmdEntry::dispatch (this=0x84181b4, inputs=@0x77da14fc, outputs=0x77da14e0) at xrl_cmd_map.hh:37
#15 0x0825da1a in XrlDispatcher::dispatch_xrl (this=0x77da9648, method_name=@0x77da1470, inputs=@0x77da14fc,
     outputs=@0x77da14e0) at xrl_dispatcher.cc:60
#16 0x08240d19 in XrlRouter::dispatch_xrl (this=0x77da9648, method_name=@0x77da14f8, inputs=@0x77da14fc,
     outputs=@0x77da14e0) at xrl_router.cc:587
#17 0x08265efd in STCPRequestHandler::dispatch_request (this=0x847dc20, seqno=1249, packed_xrl=0x6fd0987c "?",
     packed_xrl_bytes=101) at xrl_pf_stcp.cc:235
#18 0x082665d3 in STCPRequestHandler::read_event (this=0x847dc20, ev=BufferedAsyncReader::DATA,
     buffer=0x6fd09864 "STCP\001\001", buffer_bytes=125) at xrl_pf_stcp.cc:199
#19 0x08267bcc in XorpMemberCallback4B0<void, STCPRequestHandler, BufferedAsyncReader*, BufferedAsyncReader::Event, unsigned char*, unsigned int>::dispatch (this=0x8446dc0, a1=0x847dc28, a2=BufferedAsyncReader::DATA,
     a3=0x6fd09864 "STCP\001\001", a4=125) at ../libxorp/callback_nodebug.hh:8965
#20 0x0828c0b3 in BufferedAsyncReader::announce_event (this=0x847dc28, ev=BufferedAsyncReader::DATA)
     at buffered_asyncio.cc:248
#21 0x0828c3f2 in BufferedAsyncReader::io_event (this=0x847dc28, fd={_filedesc = 51}, type=IOT_READ)
     at buffered_asyncio.cc:201
#22 0x0828cc34 in XorpMemberCallback2B0<void, BufferedAsyncReader, XorpFd, IoEventType>::dispatch (this=0x847ab18, a1=
       {_filedesc = 51}, a2=IOT_READ) at ../libxorp/callback_nodebug.hh:4635
#23 0x082a8766 in SelectorList::Node::run_hooks (this=0x84750dc, m=SEL_RD, fd={_filedesc = 51}) at selector.cc:149
#24 0x082a73d1 in SelectorList::wait_and_dispatch (this=0x77daa4e4, timeout=@0x77da95d0) at selector.cc:435
---Type <return> to continue, or q <return> to quit---
#25 0x0828e5a0 in EventLoop::run (this=0x77daa4a8) at eventloop.cc:137
#26 0x0804d192 in fea_main (finder_hostname=@0x77daa6c0, finder_port=19999) at xorp_fea.cc:101
#27 0x0804d478 in main (argc=0, argv=0x77daa788) at xorp_fea.cc:175
(gdb) frame 4
#4  0x081069a8 in FibConfigEntrySetNetlinkSocket::add_entry (this=0x842ee50, fte=@0x77d9d2d4)
     at fibconfig_entry_set_netlink_socket.cc:259
259     fibconfig_entry_set_netlink_socket.cc: No such file or directory.
         in fibconfig_entry_set_netlink_socket.cc
(gdb) print fte
$1 = (const FteX &) @0x77d9d2d4: {<Fte<IPvX,IPvXNet>> = {_net = {<IPNet<IPvX>> = {_masked_addr = {_addr = {196874, 0,
             0, 0}, _af = 2}, _prefix_len = 24}, <No data fields>}, _nexthop = {_addr = {67503114, 0, 0, 0}, _af = 2},
     _ifname = {static npos = 4294967295,
       _M_dataplus = {<std::allocator<char>> = {<__gnu_cxx::new_allocator<char>> = {<No data fields>}, <No data fields>}, _M_p = 0x847c4fc "4.6.6"}}, _vifname = {static npos = 4294967295,
       _M_dataplus = {<std::allocator<char>> = {<__gnu_cxx::new_allocator<char>> = {<No data fields>}, <No data fields>}, _M_p = 0x8444bf4 "4.6.6"}}, _metric = 3, _admin_distance = 110, _xorp_route = true, _is_deleted = false,
     _is_unresolved = false, _is_connected_route = false}, <No data fields>}
(gdb)





-- 
Ben Greear <greearb at candelatech.com>
Candela Technologies Inc  http://www.candelatech.com