In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix race condition between session lookup and expire Thread A + Thread B ksmbd_session_lookup | smb2_sess_setup sess = xa_load | | | xa_erase(&conn->sessions, sess->id); | | ksmbd_session_destroy(sess) --> kfree(sess) | // UAF! | sess->last_active = jiffies | + This patch add rwsem to fix race condition between ksmbd_session_lookup and ksmbd_expire_session.
The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.