In the Linux kernel, the following vulnerability has been resolved:
Revert "xsk: Support redirect to any socket bound to the same umem"
This reverts commit 2863d665ea41282379f108e4da6c8a2366ba66db.
This patch introduced a potential kernel crash when multiple napi instances redirect to the same AFXDP socket. By removing the queueindex check, it is possible for multiple napi instances to access the Rx ring at the same time, which will result in a corrupted ring state which can lead to a crash when flushing the rings in _xskflush(). This can happen when the linked list of sockets to flush gets corrupted by concurrent accesses. A quick and small fix is not possible, so let us revert this for now.