[OE-core] [PATCH v2] Fix cp's target path for ext* filesystems

[André Draszik]

On Fri, 2019-02-08 at 00:20 -0800, Leonardo Augusto wrote:
> Python subprocess' shell=True defaults to /bin/sh[1][2], which
> often refers to a POSIX-compliant shell. As the -e flag is
> not defined in the POSIX standard[3], some shells may
> interpret "-e" as the first argument to the echo command,
> causing the rest of the command line to fail.
> 
> In this particular case, "echo -e 'cd {}'" is interpreted
> as "-e cd {}", which causes the first line of the command
> to fail, and causing cp to always place the source file
> in the filesystem's root.
> 
> This issue only affects "wic cp" for ext* filesystems.
> 
> [1] https://docs.python.org/2/library/subprocess.html
> [2] https://docs.python.org/3/library/subprocess.html
> [3] http://pubs.opengroup.org/onlinepubs/9699919799
> 
> Signed-off-by: Leonardo Augusto <leobsd at gmail.com>
> ---
>  scripts/lib/wic/engine.py | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/scripts/lib/wic/engine.py b/scripts/lib/wic/engine.py
> index 4662c665c0..b4be796752 100644
> --- a/scripts/lib/wic/engine.py
> +++ b/scripts/lib/wic/engine.py
> @@ -331,7 +331,7 @@ class Disk:
>      def copy(self, src, pnum, path):
>          """Copy partition image into wic image."""
>          if self.partitions[pnum].fstype.startswith('ext'):
> -            cmd = "echo -e 'cd {}\nwrite {} {}' | {} -w {}".\
> +            cmd = "echo 'cd {}\nwrite {} {}' | {} -w {}".\

This causes some shell's echos to output a literal \n (two characters, '\'
and 'n').

The solution should be to use printf instead of echo...

Cheers,
Andre'

>                        format(path, src, os.path.basename(src),
>                               self.debugfs, self._get_part_image(pnum))
>          else: # fat
> -- 
> 2.17.1
>