Bluetooth: ISO: fix refcounting of iso_conn
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.8epss 0.4%
exploitation probability
0.4%top 71% of all CVEs
observed exploitation
nono source reports it
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: fix refcounting of iso_conn
iso_conn_del() and iso_chan_del() have a race that results to double-put
of iso_conn:
[Task hdev->workqueue] [Task 2]
iso_conn_del iso_chan_del
iso_conn_hold_unless_zero iso_conn_lock
iso_conn_lock conn->sk = NULL
iso_conn_unlock
sk = iso_sock_hold(conn) <---------´
if (!sk) iso_conn_put iso_conn_put
iso_conn_put /* UAF */
The extra put for !sk in iso_conn_del() is currently required since
failing iso_chan_add() may leave iso_conn not associated with any sk.
Fix by having iso_pi(sk)->conn own refcount when non-NULL, so
iso_conn_del does not need to put it. Adjust the iso_conn_add()
refcounting so that conn is put if it does not get associated with an
sk.
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Linux · Linux