TomatoUSB

Hi all.
I'm using Tomato firmware Version 1.28 by shibby (v105.1) and trying to configure automatic start ssh tunnel with script_init.sh.
But any attempt
autossh -y -i $somekey -R 2222:127.0.0.1:22 $somename@$somehost or just ssh -y -i $somekey -R 2222:127.0.0.1:22 $somename@$somehost
through web interface (Tools-> System) or script_init.sh fails:
ssh: Warning: failed creating //.ssh: Read-only file system
Host '$somehost' is not in the trusted hosts file.
(fingerprint md5 $somehash)
ssh: Connection to $somename@$somehost exited: Didn't validate host key

Ok, this is because the directory /www mounted read-only.
mount -o remount, rw
had no effect, then I tried to copy all files from /www whith saving all permission to /jffs
cp -rp /www /jffs/www
and mount it with startup script in the original /www
mount -o noatime /jiffs/www /www
but it only broke the web interface with errors "503 read access error"
Does anyone have experience ssh connection without file known_hosts, or adding it to nvram router?
Thanks for reading and sorry for my terrible english.