[Bug-cpio] Re: Bug#565474: cpio makes device nodes into hard links when copying out of a cramfs image

[Carl Miller]

On Sat, Jan 16, 2010 at 05:09:45AM +0000, Clint Adams wrote:
> 
> You mean something like this?
> 
> 
> diff --git a/src/copyout.c b/src/copyout.c
> index 98f3895..f0741f7 100644
> --- a/src/copyout.c
> +++ b/src/copyout.c
> @@ -121,7 +121,9 @@ count_defered_links_to_dev_ino (struct cpio_file_stat 
> *file_hdr)
>    for (d = deferouts; d != NULL; d = d->next)
>      {
>        if ( (d->header.c_ino == ino) && (d->header.c_dev_maj == maj)
> -       && (d->header.c_dev_min == min) )
> +       && (d->header.c_dev_min == min)
> +       && ((d->header.c_mode & CP_IFBLK) != CP_IFBLK)
> +       && ((d->header.c_mode & CP_IFCHR) != CP_IFCHR) )
>       ++count;
>      }
>    return count;
> @@ -178,7 +180,9 @@ writeout_other_defers (struct cpio_file_stat *file_hdr, 
> int out_des)
>    while (d != NULL)
>      {
>        if ( (d->header.c_ino == ino) && (d->header.c_dev_maj == maj)
> -       && (d->header.c_dev_min == min) )
> +       && (d->header.c_dev_min == min)
> +       && ((d->header.c_mode & CP_IFBLK) != CP_IFBLK)
> +       && ((d->header.c_mode & CP_IFCHR) != CP_IFCHR) )
>       {
>         struct deferment *d_free;
>         d->header.c_filesize = 0;


Most excellent!  Thank you, Clint!  I'll try it out first thing Monday
morning.  I hadn't had a chance to download and poke through the cpio
source yet, having only pinned down the bug clearly at 7:45 on a Friday
evening of a long, crazy day of work.

I was wondering if there's any likelihood of being tripped up by this
on any other file types (sockets? fifos?).  I spent a few minutes today
poking through the Linux kernel source, but only found where directories
get rejected for hard-linking.


                          -------Carl