Bug 178704

+++ This bug was initially created as a clone of Bug #168167 +++

Description of problem:
scp currently implements local-to-local copy by constructing a command line
using 'cp' in a string and then using system().  Beside the fact the using
system() is really always wrong (only lazy people use it) which has the added
problem that the file name is exposed twice to shell expansion.  The file name
could contain characters which need quoting, like $ or spaces.  This second
expansion must be avoided.

Version-Release number of selected component (if applicable):
openssh-clients-4.2p1-1.x86_64

How reproducible:
always

Steps to Reproduce:
1.touch foo\ bar
2.mkdir somedir
3.scp foo\ bar somedir
  
Actual results:
cp: cannot stat `foo': No such file or directory
cp: cannot stat `bar': No such file or directory


Expected results:
no message, file copied

Additional info:
I'll attach a patch.  Upstream would probably not like it but it glibc is
advanced enough to provide the necessary functions.

There are also a few more places where I've seen TEMP_FAILURE_RETRY or
equivalent code missing.
-- Additional comment from drepper on 2005-09-13 00:46 EST --
Things are even bleaker than this, so I mention this separately and private.

If some manages to trick somebody to use scp like

  scp '$(touch yyy)' somedir

which should be harmless, one sees that the subexpression is executed because of
the double shell expansion.

-- Additional comment from bressers on 2005-09-19 15:53 EST --
Yes, this is a security issue.  I spent some time looking at this today, and
this distrubs me:

bress@link:/tmp/josh% ls -l
total 4
drwxrwxr-x  2 bress bress 4096 Sep 19 14:51 a
-rw-rw-r--  1 bress bress    0 Sep 19 14:51 `touch feh`
bress@link:/tmp/josh% scp * a
cp: omitting directory `a'
cp: missing destination file
Try `cp --help' for more information.
zsh: exit 1     scp * a
bress@link:/tmp/josh% ls -l
total 4
drwxrwxr-x  2 bress bress 4096 Sep 19 14:51 a
-rw-rw-r--  1 bress bress    0 Sep 19 14:52 feh
-rw-rw-r--  1 bress bress    0 Sep 19 14:51 `touch feh`


While I know most people don't use scp to move files around their local system,
I do leave off the trailing : quite often.

-- Additional comment from tmraz on 2005-09-28 16:51 EST --
Created an attachment (id=119390)
This patch uses fork + exec instead of posix_spawnp

This patch uses fork + exec instead of posix_spawnp and also fixes the remote
to remote copy.