openssh 2.2, fbsd 4.2: incoming data hangs sshd on tty

[mouring at etoh.eviladmin.org]

Can you verify this against the latest snapshot at:
http://bass.directhit.com/openssh_snap/  

2.2.0 is very old release.  Since we are on the verge (from the sounds of
it from Markus) of 2.4.0 release.

- Ben

On Mon, 25 Dec 2000 mike at hyperreal.org wrote:

> I wrote:
> > sshd, specifically the forked sshd process that is attached to a terminal
> > when a connection is made, tends to freeze when receiving data over the link.
> > The only way out is to kill -9 this process. It is easily reproducible by
> > pasting text into an editor.
> 
> With the help of someone who advised me to run ktrace on the sshd process
> that freezes, I have narrowed down the circumstances under which the problem
> is reproducible, and I discovered that sshd does receive a little bit more
> data from the paste than I get to see coming back from the editor.
> 
> It seems to have to do with whatever the pico (yes, pico, old habits die
> hard) editor is doing when it is receiving keystrokes and writing out to the
> screen. General screen repaints (ctrl-L) are fine; as are individual
> keystrokes. But pasting into the editor causes the ssh freeze-up. As I
> mentioned, there is no way to get out of it; killing the editor or the shell
> don't work; the processes stick around waiting for sshd to let them go or
> something. I have to kill the sshd process.
> 
> Contrary to earlier test results, I am unable to reproduce the problem
> outside of pico. Pasting the same text into an echo "..." command in the
> shell multiple times yielded no problems.
> 
> Tail end of the kdump follows. Note that it does not RET from the write() at
> the end:
> 
>    407 sshd     CALL  select(0x6,0xbfbff39c,0xbfbff31c,0,0)
>    407 sshd     RET   select 1
>    407 sshd     CALL  read(0x4,0xbfbfb2dc,0x4000)
>    407 sshd     GIO   fd 4 read 156 bytes
>        "\0\0\0>µ\M^XÏ¥AÐ8\M^Wl\M^_<s¢0ä\^BËH\M^A0Ñ\^W"AU\^\\M^]Á\fP-ÁCfc´\240ò\
>         ©\M^Am<\^P\M^YËo¦øoB\M^UÜ\^NþEd\^Wî\^OàF0Øp\0\0\0
>         |ª¿xû\M^]Þß¾ÊE¡Ö<-]\0\0\0>èàȸâ\aM­?ï4Ü1ø>Á\M^M®4\^Cóª\M^@wõ\M^I¼Q\^\ó\
>         Ìo\M^H\M^YYÉAÕ{=l,eèÖÃ\fb{´|\M^F\^T§»°u\M^_\M^SÜÇ?¶V"
>    407 sshd     RET   read 156/0x9c
>    407 sshd     CALL  select(0x6,0xbfbff39c,0xbfbff31c,0,0)
>    407 sshd     RET   select 1
>    407 sshd     CALL  read(0x5,0xbfbfb2dc,0x4000)
>    407 sshd     GIO   fd 5 read 8 bytes
>        "\^[[19;64H"
>    407 sshd     RET   read 8
>    407 sshd     CALL  select(0x6,0xbfbff39c,0xbfbff31c,0,0xbfbff2d4)
>    407 sshd     RET   select 1
>    407 sshd     CALL  write(0x3,0x8082000,0x6ea)
> 
> Don't know if this is helpful or not.
>