repeated crashes of hobbitd_client

[Kevin Palmer]

after a recent restart of a stable hobbit server (v4.2.0) instance (>  
1 year without issues), hobbitd_client is now repeatedly crashing.  a  
sanitized version of what gdb reports follows:

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This GDB was configured as "i386-redhat-linux-gnu"...Using host  
libthread_db library "/lib/tls/libthread_db.so.1".

Core was generated by `hobbitd_client'.
Program terminated with signal 6, Aborted.
Reading symbols from /lib/libpcre.so.0...done.
Loaded symbols for /lib/libpcre.so.0
Reading symbols from /lib/tls/libc.so.6...done.
Loaded symbols for /lib/tls/libc.so.6
Reading symbols from /lib/ld-linux.so.2...done.
Loaded symbols for /lib/ld-linux.so.2
#0  0x003d17a2 in _dl_sysinfo_int80 () from /lib/ld-linux.so.2
(gdb) bt
#0  0x003d17a2 in _dl_sysinfo_int80 () from /lib/ld-linux.so.2
#1  0x004127a5 in raise () from /lib/tls/libc.so.6
#2  0x00414209 in abort () from /lib/tls/libc.so.6
#3  0x0805d4e6 in sigsegv_handler (signum=11) at sig.c:57
#4  <signal handler called>
#5  rbtFind (h=0x0, key=0x8f25178) at rbtr.c:379
#6  0x08054cb8 in getrule (hostname=0x8f25178 "hostname.foo.com",
     pagename=0x8f246e0 "oldprod", classname=0xb7e7b04f "linux",
     ruletype=C_LOAD) at client_config.c:237
#7  0x08054f32 in get_cpu_thresholds (hinfo=0x8f246e0,
     classname=0xb7e7b04f "linux", loadyellow=0xbfee0654,  
loadred=0xbfee0658,
     recentlimit=0xbfee065c, ancientlimit=0xbfee0660,  
maxclockdiff=0xbfee0664)
     at client_config.c:1209
#8  0x08049fde in unix_cpu_report (
     hostname=0xb7e7b033 "hostname.foo.com",
     clientclass=0xb7e7b04f "linux", os=OS_LINUX, hinfo=0x8f25110,
     fromline=0xbfee1810 "\nStatus message received from  
xxx.xxx.xxx.xxx\n",
     timestr=0xb7e7b085 "Tue Oct 30 23:19:57 PDT 2007",
     uptimestr=0xb7e7b128 " 23:19:57  up 71 days,  1:14,  0 users,   
load average: 0.29, 0.23, 0.19",
     clockstr=0xb7e94e94 "epoch: 1193811603.588122\nlocal: 2007-10-30  
23:20:03 PDT\nUTC: 2007-10-31 06:20:03 GMT\n", msgcachestr=0x0,  
whostr=0xb7e7b175 "",
     psstr=0xb7e7eca3 "  PID  PPID USER      STARTED S PRI %CPU      
TIME %MEM  RSZ   VSZ CMD\n    1     0 root       Aug 20 S  24  0.0  
00:00:49  0.0  504  1540 init\n    2     0 root       Aug 20 S 139   
0.0 00:00:00  0.0    0"...,
     topstr=0xb7e8afca "\n\n 23:19:58  up 71 days,  1:14,  0 users,   
load average: 0.29, 0.23, 0.19\n526 processes: 525 sleeping, 1  
running, 0 zombie, 0 stopped\nCPU states:  cpu    user    nice   
system    irq  softirq  iowait  "...)
     at hobbitd_client.c:263
#9  0x0804d035 in handle_linux_client (
     hostname=0xb7e7b033 "hostname.foo.com",
     clienttype=0xb7e7b04f "linux", os=OS_LINUX, hinfo=0x8f25110,
     sender=0xb7e7b025 "xxx.xxx.xxx.xxx", timestamp=1193811604,
     clientdata=0xb7e7b055 "client hostname,foo,com.linux linux\n[date")
     at client/linux.c:55
#10 0x080514ed in main (argc=1, argv=0xbfee1e24) at hobbitd_client.c: 
1788