CVSS7.8
Severityhigh
Weakness—
ExploitedNot in CISA KEV
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Description
In the Linux kernel, the following vulnerability has been resolved: dibs: fix use-after-free of dmb_node in loopback attach/detach/unregister dibs_lo_attach_dmb(), dibs_lo_detach_dmb() and dibs_lo_unregister_dmb() look up the dmb_node under dmb_ht_lock, drop the lock and only then operate on the node's refcount. Nothing keeps the node alive across that window: __dibs_lo_unregister_dmb() removes the node from the hash table under the write lock and immediately frees it. A concurrent final put can therefore free the node between the lookup and the refcount operation: CPU0 (attach) CPU1 (owner unregisters) read_lock_bh(&dmb_ht_lock) find dmb_node (refcnt == 1) read_unlo