Bug#230281: libc6: Various programs segfault in __ns_samename in libresolv.so.2
Package: libc6
Version: 2.3.2.ds1-10
Severity: normal
Various programs die with a segmentation fault in __ns_samename when
given a nonexistent network address. For example, "ping qwerty", "finger
@qwerty", and "wget http://qwerty/"; do this (when no host "qwerty"
exists). They do manage to print out an error message from the failed
query, and the segfault happens when they try to exit.
Here's a small program that segfaults:
------------------------------
#include <netdb.h>
#include <stdlib.h>
int main()
{
gethostbyname("qwerty");
exit(1);
}
------------------------------
vaino:/tmp> gdb ./foo
GNU gdb 5.3-debian
Copyright 2002 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty" for details.
This GDB was configured as "i386-linux"...
(gdb) run
Starting program: /tmp/foo
Program received signal SIGSEGV, Segmentation fault.
0x4c457f00 in ?? ()
(gdb) bt
#0 0x4c457f00 in ?? ()
#1 0x40174e66 in __ns_samename () from /lib/libresolv.so.2
#2 0x4000c4e6 in _dl_init () from /lib/ld-linux.so.2
#3 0x400548f2 in exit () from /lib/libc.so.6
#4 0x080483bc in main () at foo.c:7
#5 0x4003eda6 in __libc_start_main () from /lib/libc.so.6
(gdb) info shared
>From To Syms Read Shared Object Library
0x4003ebc0 0x40134278 Yes /lib/libc.so.6
0x40000be0 0x40011d5f Yes /lib/ld-linux.so.2
0x4015cd70 0x40162e10 Yes /lib/libnss_files.so.2
0x40164e90 0x40166e20 Yes /lib/libnss_dns.so.2
0x4016a980 0x40174e50 Yes /lib/libresolv.so.2
(gdb) info registers
eax 0x40168003 1075216387
ecx 0x40152148 1075126600
edx 0x4c457f00 1279622912
ebx 0x401776d0 1075279568
esp 0xbffff96c 0xbffff96c
ebp 0xbffff978 0xbffff978
esi 0x804a460 134521952
edi 0x401775fc 1075279356
eip 0x4c457f00 0x4c457f00
eflags 0x10216 66070
cs 0x23 35
ss 0x2b 43
ds 0x2b 43
es 0x2b 43
fs 0x0 0
gs 0x0 0
fctrl 0x37f 895
fstat 0x0 0
ftag 0xffff 65535
fiseg 0x0 0
fioff 0x0 0
foseg 0x0 0
fooff 0x0 0
fop 0x0 0
mxcsr 0x1f80 8064
orig_eax 0xffffffff -1
(gdb) x/16i $pc
0x4c457f00: add %al,(%eax)
0x4c457f02: add %al,(%eax)
0x4c457f04: add %al,(%eax)
0x4c457f06: add %al,(%eax)
0x4c457f08: add %al,(%eax)
0x4c457f0a: add %al,(%eax)
0x4c457f0c: add %al,(%eax)
0x4c457f0e: add %al,(%eax)
0x4c457f10: add %al,(%eax)
0x4c457f12: add %al,(%eax)
0x4c457f14: add %al,(%eax)
0x4c457f16: add %al,(%eax)
0x4c457f18: add %al,(%eax)
0x4c457f1a: add %al,(%eax)
0x4c457f1c: add %al,(%eax)
0x4c457f1e: add %al,(%eax)
-- System Information:
Debian Release: testing/unstable
Architecture: i386
Kernel: Linux vaino 2.4.23 #1 Thu Dec 4 20:46:59 EET 2003 i686
Locale: LANG=en_IE@euro, LC_CTYPE=en_IE@euro
Versions of packages libc6 depends on:
hi libdb1-compat 2.1.3-7 The Berkeley database routines [gl
-- no debconf information
Reply to: