[libvirt] [PATCHv2] Ignore bridge template names with multiple printf conversions

[Eric Blake]

On 05/05/2015 10:05 AM, Ján Tomko wrote:
> For some reason, we allow a bridge name with %d in it, which we replace
> with an unsigned integer to form a bridge name that does not yet exist
> on the host.
> 
> Do not blindly pass it to virAsprintf if it's not the only conversion,
> to prevent crashing on input like:
> 
> <network>
>   <name>test</name>
>   <forward mode='none'/>
>   <bridge name='virbr%d%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s'/>
> </network>
> 
> Ignore any template strings that do not have exactly one %d conversion,
> like we do in various drivers before calling virNetDevTapCreateInBridgePort.
> ---
> v2: drop the unnecessary changes in networkBridgeNameValidate
> 
>  src/network/bridge_driver.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
> index 3b879cd..fe2448d 100644
> --- a/src/network/bridge_driver.c
> +++ b/src/network/bridge_driver.c
> @@ -2775,7 +2775,13 @@ networkFindUnusedBridgeName(virNetworkObjListPtr nets,
>  
>      int ret = -1, id = 0;
>      char *newname = NULL;
> -    const char *templ = def->bridge ? def->bridge : "virbr%d";
> +    const char *templ = "virbr%d";
> +    const char *p;

Unused variable.

> +
> +    if (def->bridge &&
> +        (p = strchr(def->bridge, '%')) == strrchr(def->bridge, '%') &&
> +        strstr(def->bridge, "%d"))

Simpler as:

if (def->bridge &&
    strstr(def->bridge, "%d") == strrchr(def->bridge, '%'))

ACK with that simplification.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 604 bytes
Desc: OpenPGP digital signature
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20150505/4c83c087/attachment-0001.sig>