CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's Bluetooth implementation, specifically in the iso_conn_big_sync() function, where a NULL pointer dereference can occur if the connection is torn down while the socket lock is temporarily released. This flaw could lead to system instability or crashes when handling PA-sync broadcast sink sockets. Organizations using Linux systems with Bluetooth capabilities should prioritize addressing this vulnerability to maintain system reliability and security.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync() iso_conn_big_sync() drops the socket lock to call hci_get_route() and then re-acquires it, but dereferences iso_pi(sk)->conn->hcon afterwards without re-checking that conn is still valid. While the lock is dropped, the connection can be torn down under the same socket lock: iso_disconn_cfm() -> iso_conn_del() -> iso_chan_del() sets iso_pi(sk)->conn to NULL (and the broadcast teardown path can also clear conn->hcon on its own). When iso_conn_big_sync() re-acquires the lock and reads conn->hcon, conn may be NULL, causing a NULL pointer dereference (hcon is the first member of struct iso_conn). This path is reached from iso_sock_recvmsg() for a PA-sync broadcast sink socket (BT_SK_DEFER_SETUP | BT_SK_PA_SYNC), so the dropped-lock window can race with connection teardown driven by controller events. Re-validate iso_pi(sk)->conn and its hcon after re-acquiring the socket lock and bail out if the connection went away, as already done in the sibling iso_sock_rebind_bc().