CVE-2026-23367

In the Linux kernel, the following vulnerability has been resolved:

wifi: radiotap: reject radiotap with unknown bits

The radiotap parser is currently only used with the radiotap

namespace (not with vendor namespaces), but if the undefined

field 18 is used, the alignment/size is unknown as well. In

this case, iterator->_next_ns_data isn't initialized (it's

only set for skipping vendor namespaces), and syzbot points

out that we later compare against this uninitialized value.

Fix this by moving the rejection of unknown radiotap fields

down to after the in-namespace lookup, so it will really use

iterator->_next_ns_data only for vendor namespaces, even in

case undefined fields are present.