CVE-2026-52917

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

sctp: diag: reject stale associations in dump_one path

The SCTP exact sockdiag lookup can hold a transport reference, block on locksock(sk), and then resume after sctpassociationfree() has marked the association dead and freed its bind address list.

When that happens, inetassocattrsize() and inetdiagmsgsctpasocfill() can still dereference association state that is no longer valid for reporting. In particular, inetdiagmsgsctpasocfill() may read an empty bind-address list as a real sctpsockaddr_entry and trigger an out-of-bounds read from unrelated association memory.

Reject the association after taking the socket lock if it has been reaped or detached from the endpoint, and report the lookup as stale. This keeps the exact dump-one path from formatting torn association state.