Description
In the Linux kernel, the following vulnerability has been resolved: net: bridge: mdb: restart port group walk after deletion br_mdb_flush_pgs() keeps a pointer-to-pointer cursor while walking mp->ports. br_multicast_del_pg() can re-enter the same MDB entry through br_multicast_sg_del_exclude_ports() and unlink other port groups. If the cursor points into one of those groups, the next iteration dereferences a stale cursor and can leave mp->ports pointing at freed memory. A following RTM_GETMDB exposes the dangling pointer: BUG: KASAN: slab-use-after-free in br_mdb_dump Read of size 8 br_mdb_dump rtnl_mdb_dump rtnl_dumpit netlink_dump Reset the cursor to mp->ports after every deletion. The deletion removes at least the selected group, so the restarted walk always makes progress.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
a6acb535afb2a3b688a7858f05b61f0433e480d5 to < 46ec55855c972504258c371677ac039ba20e5d12affecteda6acb535afb2a3b688a7858f05b61f0433e480d5 to < ab3c4a4c85f2e1e8d04b5c1770dea8412d21c7feaffecteda6acb535afb2a3b688a7858f05b61f0433e480d5 to < fe2a42789c12eb7c5d3a42191e2cc735a6c35eadaffecteda6acb535afb2a3b688a7858f05b61f0433e480d5 to < ab1404ac81154a89fb61ac50ae9a04cd8d4834dcaffected
Linux Linux
Default version status: affected
6.8affected0 to < 6.8unaffected6.12.112 to ≤ 6.12.*unaffected6.18.55 to ≤ 6.18.*unaffected7.2.9 to ≤ 7.2.*unaffected7.3 to ≤ *unaffected