Re: Bug in scp v3.0.1

From: Matt Forrest (mforrestat_private)
Date: Wed Oct 31 2001 - 12:53:47 PST

  • Next message: Brad Arlt: "Re: Bug in scp v3.0.1"

    Try using the sftp client.  All you have to do is to connect to the
    machine and sshd2 want to eat all available CPU cycles. 
    
    I haven't looked at the source yet, but after attaching to a process, it
    looks like the daemon is sitting in a tight loop calling poll().  I'd
    think that a well placed select() call might solve the problem.
    
    On Wed, 31 Oct 2001, Jonathan A. Zdziarski wrote:
    
    > Date: Wed, 31 Oct 2001 00:18:47 -0500
    > From: Jonathan A. Zdziarski <jonathanat_private>
    > To: bugtraqat_private
    > Subject: Bug in scp v3.0.1
    > 
    > I was scp'ing a 2MB file to my home computer over a DSL line and just
    > happened to run top at the same time.  I immediately noticed this line:
    > 
    > 13864 root       1  30    0 2884K 1744K run     0:38 42.00% sshd2
    > 
    > It appears that scp'ing a file over a slow connection causes the process to
    > suck up a huge number of resources.  There's most likely no usleep()
    > somewhere it's needed.  A couple scp's over slow connections could severely
    > degrade the boxes performance.
    > 
    > This test was performed on a Solaris 8_x86 machine.
    > 
    > 
    > 
    
    
    mATT
    
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