[Libguestfs] hivex patch to solve device or resource busy error when access Windows directory while open system hive

[Richard W.M. Jones]

On Thu, Jul 07, 2011 at 06:18:46PM +0000, Michael Huang wrote:
> I have found a strange issue related to hivex/ntfs-3g. After opening a system hive on a volume mounted by ntfs-3g, any access to the Windows directory results device or resource busy error. The patch below fix it by closing the hive file handle in hivex_open() call in the writable path because the handle never been used after its content been read into memory.
> 
> --- hivex-1.2.5.orig/lib/hivex.c    2011-04-13 06:04:49.000000000 -0700
> +++ hivex-1.2.5/lib/hivex.c   2011-07-07 09:10:06.927429068 -0700
> @@ -321,6 +321,8 @@
>      if (full_read (h->fd, h->addr, h->size) < h->size)
>        goto error;
> +    close(h->fd);
> +    h->fd = -1;
>    }
>    /* Check header. */
> @@ -541,7 +543,10 @@
>      munmap (h->addr, h->size);
>    else
>      free (h->addr);
> -  r = close (h->fd);
> +  if (h->fd >= 0)
> +       r = close (h->fd);
> +  else
> +       r = 0;
>    free (h->filename);
>    free (h);
> 


I've pushed this, slightly modified.

Thanks for your contribution!

Rich.

-- 
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