[Qemu-devel] Re: [PATCH] pci: fix pcibus_get_dev_path()

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Jan 20, 2011 at 06:31:59PM +0800, TeLeMan wrote:
> The commit 6a7005d14b3c32d4864a718fb1cb19c789f58a5 used snprintf() incorrectly.
> 
> Signed-off-by: TeLeMan <geleman@gmail.com>

This won't work for nested bridges as \n by the first
sprintf overwrites the rest of the string.
I sent a fix titled
[PATCH] pci: fix device paths
look it up.

> ---
>  hw/pci.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/pci.c b/hw/pci.c
> index 8d0e3df..9f8800d 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -2050,14 +2050,14 @@ static char *pcibus_get_dev_path(DeviceState *dev)
>      path[path_len] = '\0';
> 
>      /* First field is the domain. */
> -    snprintf(path, domain_len, "%04x:00", pci_find_domain(d->bus));
> +    snprintf(path, domain_len + 1, "%04x:00", pci_find_domain(d->bus));
> 
>      /* Fill in slot numbers. We walk up from device to root, so need to print
>       * them in the reverse order, last to first. */
>      p = path + path_len;
>      for (t = d; t; t = t->bus->parent_dev) {
>          p -= slot_len;
> -        snprintf(p, slot_len, ":%02x.%x", PCI_SLOT(t->devfn),
> PCI_FUNC(d->devfn));
> +        snprintf(p, slot_len + 1, ":%02x.%x", PCI_SLOT(t->devfn),
> PCI_FUNC(d->devfn));
>      }
> 
>      return path;
> -- 
> 1.7.3.1.msysgit.0