If my laptop or other computer is tied to a wired network, and it automatically joins a wifi router attached to that same network, can the two connections to the network cause a loop that starts a broadcast storm?
Assume STP is off... of course.
Probably not as each interface will have it's own MAC address (as well as it's own IP address).
Name resolution may be a problem, but that's all I would expect to see in such a scenario.
No, because your computer is probably not forwarding arbitrary packets it receives.
I used to run this way in the office. My computer has wireless enabled all the time, and when it is docked, it has a physical link to the same network.
(Now I have unplugged the wire so that when I undock, my laptop doesn't suddenly lose the IP address it was using to talk on the network.)
By "same network" you likely mean "same broadcast domain."
On a workstation with a wired interface (10/100/1000Base-T Ethernet NIC) and wireless interface (802.11a/b/g/n NIC) connected to the same broadcast domain -- the default paradigm for all mainstream operating systems that I know of will not create a broadcast storm.
These interfaces are considered layer 3, IP interfaces. Layer 3 interfaces in general segment broadcast domains. It is of special note that you can enable IP forwarding in your operating system with
Quick and dirty Linux:
REG_DWORD set to 1.
However, enabling IP fowarding will still not create broadcast storms in your example.
To do that you would have to "bridge" the two interfaces at layer 2 -- essentially turning your workstation into a two port bridge/switch. With your workstation/2 port switch "connected" upstream to the same broadcast domain on both workstation ports (the wired and wireless interfaces) you have created a layer 2 loop -- and a broadcast storm can result.
I say can because if your upstream switch is running spanning tree -- it is likely that one of the interfaces on the upstream switch with be placed in a blocking state as the workstation's "two port bridge/switch" software capability is oftentimes not STP aware and will forward on BPDU's.