Description · from the CVE record
In the Linux kernel, the following vulnerability has been resolved:
net: bridge: stop fast-leave after deleting a port group
br_multicast_leave_group() iterates mp->ports with pp = &p->next in
its fast-leave path. After br_multicast_del_pg() removes p,
continuing the loop advances pp through the deleted entry.
If multicast-to-unicast was enabled, the bridge can hold multiple port
groups for the same port and group with different source MAC
addresses. Once multicast-to-unicast is disabled,
br_port_group_equal() matches those entries by port only. A fast leave
can then delete one entry and continue from its stale next pointer,
leaving mp->ports pointing at a deleted port group.
Fast leave only needs to remove one matching port group. Break after
br_multicast_del_pg() so the loop stops before dereferencing the
removed entry.
Affected
ProductAffectedFixed inSource
Linux6db6f0eae6052b70885562e1733896647ec1d807 – < d6c32e2e25a9a06ba021030e26b6d602a277eb72d6c32e2e25a9a06ba021030e26b6d602a277eb72CNA
Linux6db6f0eae6052b70885562e1733896647ec1d807 – < 482bcb85139addb4e8ac8ed10baeda3e0aad4031482bcb85139addb4e8ac8ed10baeda3e0aad4031CNA
Linux6db6f0eae6052b70885562e1733896647ec1d807 – < 1a109cc9890d017c41d77e6c82da739579c49f0b1a109cc9890d017c41d77e6c82da739579c49f0bCNA
Linux6db6f0eae6052b70885562e1733896647ec1d807 – < 159ad90cb929c033308bb39a2c5f8fbf393b77aa159ad90cb929c033308bb39a2c5f8fbf393b77aaCNA
Linux6db6f0eae6052b70885562e1733896647ec1d807 – < 4695430e8132420bf8de94da3eb36a6cf35fde6b4695430e8132420bf8de94da3eb36a6cf35fde6bCNA
Linux6db6f0eae6052b70885562e1733896647ec1d807 – < 0309ebbc570000ea0df11c06b69798e5860c5f6f0309ebbc570000ea0df11c06b69798e5860c5f6fCNA
Linux6db6f0eae6052b70885562e1733896647ec1d807 – < 4c57056ca6aace2e9f94ae9298bf49ef6b0c95e44c57056ca6aace2e9f94ae9298bf49ef6b0c95e4CNA
Linux6db6f0eae6052b70885562e1733896647ec1d807 – < a39789f211b8a4125f0c70e05b30cf715f4f187da39789f211b8a4125f0c70e05b30cf715f4f187dCNA
Linux4.11–CNA
by Kastro