[Valgrind-users] Bad permissions for mapped region & SIGSEGV

[David C. <dc...@gm...>]

Hi,

We're seeing some crash behaviour in system routines such as gethostbyname.

This only manifests itself on our newer machines - our old 32bit machines
do not have this behaviour.

Any idea what can cause it or how to fix it? Not supplying an special
options to memcheck or valgrind.  Tech details below.

Thanks,
David.

valgrind version:
valgrind-3.9.0

uname -a:
Linux hostname 2.6.18-194.3.1.el5 #1 SMP Sun May 2 04:17:42 EDT 2010 x86_64
x86_64 x86_64 GNU/Linux

cat /proc/cpuinfo:
processor : 22
vendor_id : GenuineIntel
cpu family : 6
model : 44
model name : Intel(R) Xeon(R) CPU X5680 @ 3.33GHz
stepping : 2 cpu
MHz : 3333.597
cache size : 12288 KB
physical id : 1
siblings : 12
core id : 9
cpu cores : 6
apicid : 51
fpu : yes
fpu_exception : yes
cpuid level : 11
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat
pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx pdpe1gb rdtscp
lm constant_tsc nonstop_tsc arat pni monitor ds_cpl vmx smx est tm2 ssse3
cx16 xtpr sse4_1 sse4_2 popcnt lahf_lm
bogomips : 6666.80
clflush size : 64
address sizes : 40 bits physical, 48 bits virtual power management: [8]

valgrind log:

starts with...

==29802== Thread 2:
==29802== Invalid read of size 4
==29802== at 0x3860209336: __libc_res_nsend (in /lib64/libresolv-2.5.so)
==29802== by 0x37FFFFFFFF: ???
==29802== by 0x3860207E95: __libc_res_nquerydomain (in /lib64/
libresolv-2.5.so)
==29802== by 0x38602081BF: __libc_res_nsearch (in /lib64/libresolv-2.5.so)
==29802== by 0x3238C96E: _nss_dns_gethostbyname3_r (in /lib64/
libnss_dns-2.5.so)
==29802== by 0x3238CB5D: _nss_dns_gethostbyname_r (in /lib64/
libnss_dns-2.5.so)
==29802== by 0x2B97CA8F: ???
==29802== by 0x26B66D8D: ???
==29802== by 0x2B97CC1F: ???
==29802== by 0x2B97CC37: ???
==29802== by 0x385DE03A87: ??? (in /lib64/libc-2.5.so)
==29802== Address 0x2b97b37c is on thread 2's stack

lots of that repeated, then finally:

==29802== Process terminating with default action of signal 11 (SIGSEGV)
==29802== Bad permissions for mapped region at address 0x3800000000
==29802== at 0x3800000000: ???
==29802== by 0x3860207E95: __libc_res_nquerydomain (in /lib64/
libresolv-2.5.so)
==29802== by 0x38602081BF: __libc_res_nsearch (in /lib64/libresolv-2.5.so)
==29802== by 0x3238C96E: _nss_dns_gethostbyname3_r (in /lib64/
libnss_dns-2.5.so)
==29802== by 0x3238CB5D: _nss_dns_gethostbyname_r (in /lib64/
libnss_dns-2.5.so)
==29802== by 0x2B97CA8F: ???
==29802== by 0x26B66D8D: ???
==29802== by 0x2B97CC1F: ???
==29802== by 0x2B97CC37: ???
==29802== by 0x385DE03A87: ??? (in /lib64/libc-2.5.so)