Hello everybody,

Yesterday I have got a problem what till now I cound not solve. I used google, I have read a lot of forum but I could not find the answer.
If I would like to add a new user with useradd (on Debian 4.0), I get the message Segmentation fault. I made a strace, that says:
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
I have read maybe the libc6 is missing or damaged, so I installed it again (apt-get install libc6, install was successfull), but the problem is still there. I touched it (touch /etc/ld.so.nohwcap), doesn't help.
Could somebody tell me something what can be the problem?

Drop caches and try again,
If that fixes it, a cosmic ray flipped a bit in your RAM.

Else try reinstalling the 'passwd' package.

Hello,

thanks for the fast reply and for your help. The echo 3 > /proc/sys/vm/drop_caches did nothing, but the passwd reinstall solved the problem. Thanks a lot!
How could it happen? Nobody disturbed the server and from one day to the other...?

The straces /etc/ld.so.nohwcap ENOENT does or should not relate to your problem (man ld.so). It's best to attach a complete strace instead of picking out arbitrary lines. The segmentation fault error message means the application tried to access or change part of memory it did not have rights to. (If the previous version of useradd left a core file you could have then run 'gdb useradd core', then type "bt" for the stack trace.) So in the absence of information any questions about segfaulting can only lead to speculation...

Possibly bit corruption. It happens, though it's rare on a hard drive.

Like I said already: speculation ;-p

Here's the original (full) output:

execve("/usr/sbin/useradd", ["useradd", "evilparameters"], [/* 16 vars */]) = 0
uname({sys="Linux", node="Mailserv", ...}) = 0
brk(0) = 0x805f000
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
mmap2(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7f88000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat64(3, {st_mode=S_IFREG|0644, st_size=19972, ...}) = 0
mmap2(NULL, 19972, PROT_READ, MAP_PRIVATE, 3, 0) = 0xb7f83000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/tls/i686/cmov/libcrypt.so.1", O_RDONLY) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0@\10\0\000"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0644, st_size=21868, ...}) = 0
mmap2(NULL, 184636, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7f55000
mmap2(0xb7f5a000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x4) = 0xb7f5a000
mmap2(0xb7f5c000, 155964, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xb7f5c000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/libselinux.so.1", O_RDONLY) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0P8\0\000"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0644, st_size=79368, ...}) = 0
mmap2(NULL, 84884, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7f40000
mmap2(0xb7f53000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x12) = 0xb7f53000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/tls/i686/cmov/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\240O\1"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0644, st_size=1241392, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7f3f000
mmap2(NULL, 1247388, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7e0e000
mmap2(0xb7f35000, 28672, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x127) = 0xb7f35000
mmap2(0xb7f3c000, 10396, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xb7f3c000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/tls/i686/cmov/libdl.so.2", O_RDONLY) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\20\f\0"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0644, st_size=9592, ...}) = 0
mmap2(NULL, 12404, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7e0a000
mmap2(0xb7e0c000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1) = 0xb7e0c000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/libsepol.so.1", O_RDONLY) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\0200\0"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0644, st_size=219824, ...}) = 0

The /etc/ld.so.preload-problem was fixed by libc6 reinstall.

Thanks but I don't see it segfaulting anywhere.


Don't say it's a "/etc/ld.so.preload problem" because it isn't. Again some files not existing is no reason for it to segfault and /etc/ld.so.preload is one of them ('man ld.so again').