Activity log
- Created & dismissed (max. allowed matches exceeded) suggestion
netfilter: revalidate bridge ports
In the Linux kernel, the following vulnerability has been resolved: netfilter: revalidate bridge ports ebt_redirect_tg() dereferences br_port_get_rcu() return without a NULL check, causing a kernel panic when the bridge port has been removed between the original hook invocation and an NFQUEUE reinject. A mere NULL check isn't sufficient, however. As sashiko review points out userspace can not only remove the port from the bridge, it could also place the device in a different virtual device, e.g. macvlan. If this happens, we must drop the packet, there is no way for us to reinject it into the bridge path. Switch to _upper API, we don't need the bridge port structure. Also, this fix keeps another bug intact: Both nfnetlink_log and nfnetlink_queue use CONFIG_BRIDGE_NETFILTER too aggressive, which prevents certain logging features when queueing in bridge family: NETFILTER_FAMILY_BRIDGE can be enabled while the old CONFIG_BRIDGE_NETFILTER cruft is off. Fixes tag is a common ancestor, this was always broken.
References
Affected products
- <ccb9fd4b87538ccf19ccff78ee26700526d94867
- =<6.18.*
- ==2.6.36
- =<7.0.*
- <4beffcd726e2a731cea4dc18e1fbc55c8d76f1a0
- =<6.12.*
- <d4b1301fd3c9e5e105fd3767c68bc4ba558bb228
- <43330a1e8aace6b5a8de9aba127e9e394ab49b0f
- <2.6.36
- =<*