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Topic: sshd (or dropbear) segmentation fault

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Dear all,

I have a strange problem with sshd or dropbear. After launching the daemon I can establish only a connection, after there the daemon dead (with a segmentation fault...).

Seems that the daemon is not able to fork...

Any idea?

I'm working to use openwrt Kamikaze-7.07 on a mips demoboard with a mips32 4kc, 32M Ram and 16M Flash).

additional information:
uClibc 0.9.28.2 (built-in kamikaze)
gcc suite 4.1.2 (built-in kamikaze)
linux kernel 2.6.15 patched to support (I don't have the patches).

mount (I use a ro nfs root fs, but I have same problems with squashfs on flash)

/dev/root on / type nfs (ro,v2,rsize=4096,wsize=4096,hard,nolock,proto=udp,addr=10.3.3.53)
none on /proc type proc (rw,nodiratime)
none on /sys type sysfs (rw)
none on /tmp type tmpfs (rw,nosuid,nodev)
tmpfs on /dev type tmpfs (rw)
none on /dev/pts type devpts (rw)
/var/etc_ram on /etc type bind (bind)
none on /dev/shm type tmpfs (rw,noexec,nosuid,nodev)

Thanks a lot.

luigi

I add some useful information:

System features:

MIP32 4kec system 32M Ram, 16M Flash (custom board)
gcc 4.2 (I tried 4.1.2 also)
uclibc 0.9.28.2
Kamikaze 7.07 (from svn)

mount:
rootfs on / type rootfs (rw)
/dev/root on / type nfs (rw,v2,rsize=4096,wsize=4096,hard,nolock,proto=udp,addr=10.3.3.52)
none on /proc type proc (rw,nodiratime)
none on /sys type sysfs (rw)
none on /tmp type tmpfs (rw,nosuid,nodev)
tmpfs on /dev type tmpfs (rw)
none on /dev/pts type devpts (rw)

memory:
Mem: 6600K used, 20228K free, 0K shrd, 0K buff, 3812K cached
Load average: 0.00 0.00 0.00

strace sshd invocation (stderr)

root@OpenWrt:/# strace -ff -F -o sshlog3 /usr/sbin/sshd -D
_dl_get_ready_to_run:197: Cool, ldso survived making function calls
_dl_malloc:899: mmapping more memory
_dl_get_ready_to_run:352: Lib Loader: (0x2aaa8000) /lib/ld-uClibc.so.0
_dl_get_ready_to_run:621: Loading: (0x2aaee000) /lib/libgcc_s.so.1
_dl_get_ready_to_run:621: Loading: (0x2ab3e000) /lib/libc.so.0
_dl_get_ready_to_run:621: Loading: (0x2ab3e000) /lib/libc.so.0
_dl_get_ready_to_run:744: Beginning relocation fixups
_dl_get_ready_to_run:197: Cool, ldso survived making function calls
_dl_malloc:899: mmapping more memory
_dl_get_ready_to_run:352: Lib Loader: (0x2aaa8000) /lib/ld-uClibc.so.0
_dl_get_ready_to_run:621: Loading: (0x2aaee000) /usr/lib/libcrypto.so.0.9.8
_dl_get_ready_to_run:621: Loading: (0x2ac30000) /lib/libutil.so.0
_dl_get_ready_to_run:621: Loading: (0x2ac72000) /usr/lib/libz.so.1
_dl_get_ready_to_run:621: Loading: (0x2acc3000) /lib/libcrypt.so.0
_dl_get_ready_to_run:621: Loading: (0x2ad19000) /lib/libresolv.so.0
_dl_get_ready_to_run:621: Loading: (0x2ad5a000) /lib/libgcc_s.so.1
_dl_get_ready_to_run:621: Loading: (0x2adaa000) /lib/libc.so.0
_dl_get_ready_to_run:621: Loading: (0x2ae8e000) /lib/libdl.so.0
_dl_get_ready_to_run:621: Loading: (0x2ad5a000) /lib/libgcc_s.so.1
_dl_get_ready_to_run:621: Loading: (0x2adaa000) /lib/libc.so.0
_dl_get_ready_to_run:621: Loading: (0x2adaa000) /lib/libc.so.0
_dl_get_ready_to_run:621: Loading: (0x2adaa000) /lib/libc.so.0
_dl_get_ready_to_run:621: Loading: (0x2ad5a000) /lib/libgcc_s.so.1
_dl_get_ready_to_run:621: Loading: (0x2adaa000) /lib/libc.so.0
_dl_get_ready_to_run:621: Loading: (0x2adaa000) /lib/libc.so.0
_dl_get_ready_to_run:621: Loading: (0x2adaa000) /lib/libc.so.0
_dl_get_ready_to_run:621: Loading: (0x2adaa000) /lib/libc.so.0
_dl_get_ready_to_run:744: Beginning relocation fixups
out of memory <----------- Strange! shown only with strace... 
Could not load host key: /etc/ssh/ssh_host_key
Disabling protocol version 1. Could not load host key

strace sshd log (sshlog3): strace -ff -F -o sshlog3 /usr/sbin/sshd -D

(I tried to connect from an external machine).

The sysctl -a output: sysctl -a

Please give me some idea to investigate.

Thanks.


luigi

(Last edited by comio on 20 Sep 2007, 09:29)

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