On Tue, May 05, 2015 at 10:14:18AM -0600, Eric Blake wrote:
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, '%'))
I still don't see it. [A] strchr(def->bridge, '%') [B] strrchr(def->bridge, '%') [C] strstr(def->bridge, "%d")) When def->bridge is '%s%s%s%d', [A] points to the first %s, [B] points to the %d and so does [C] This string would pass the simplified condition (B == C), but not the full one (A != C) Jan
ACK with that simplification.
-- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org