Problem with OpenSSH 2.3.0p1 and Linux kernel 2.4.1pre8 (Disconnecting: fork failed: Resource temporarily unavailable)

[Damien Miller]

On Mon, 29 Jan 2001, Jayme Frye wrote:

> I'm having a problem with OpenSSH 2.3.0p1 and Linux kernel 2.4.1pre8. 
> After a client connects and is authenticated ssh fails to fork, 
> disconnects and dies. Normally I run sshd out of inetd with the -i flag. 
> thinking this might be the problem I ran it in daemon mode from the 
> command line. The results were the same. Running with maximum debugging 
> on I captured the following:
> <snip>
> debug1: Local version string SSH-1.99-OpenSSH_2.3.0p1
> debug1: Sent 1152 bit public key and 1024 bit host key.
> debug1: Encryption type: 3des
> debug1: Received session key; encryption turned on.
> debug1: Installing crc compensation attack detector.
> debug1: Starting up PAM with username "adminjf"
> debug1: Attempting authentication for adminjf.
> debug1: PAM Password authentication accepted for user "adminjf"
> Accepted password for adminjf from 209.155.224.94 port 868
> debug1: PAM setting rhost to "orion.inventivecomm.com"
> debug1: session_new: init
> debug1: session_new: session 0
> debug1: Allocating pty.
> debug1: PAM setting tty to "/dev/pts/0"
> debug1: PAM establishing creds
> Disconnecting: fork failed: Resource temporarily unavailable
> debug1: Calling cleanup 0x8057aa0(0x80e47a0)
> debug1: pty_cleanup_proc: /dev/pts/0
> debug1: Calling cleanup 0x8050498(0x0)
> debug1: Calling cleanup 0x80653c8(0x0)
> 
> Under 2.2.19pre7 everything works fine. Has anyone run across 2.4 kernel 
> problems with OpenSSH?

Looks like a kernel problem to me - if fork is failing, then lots of
other things may break. 

You do have an appropriate libc for your kernel?

-d

-- 
| ``We've all heard that a million monkeys banging on | Damien Miller -
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