In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: access chan->conn safely in get/setsockopt
Since commit b66774b48dd9 ("Bluetooth: L2CAP: Fix UAF in channel timeout by holding conn ref")
l2cap_chan::conn has held reference and remains non-NULL also after the
corresponding hci_conn is deleted. In this state accessing various
fields eg. hci_conn::hdev is invalid, which leads to KASAN crash in
l2cap_sock_setsockopt() access of conn->hcon->hdev.
Check l2cap_chan::conn.hcon corresponds to an alive hci_conn before
trying to use it in l2cap_sock.c. Hold l2cap_chan_lock() in
getsockopt/setsockopt to ensure it stays alive, and to avoid data races
in l2cap_chan fields.
Bluetooth: L2CAP: access chan->conn safely in get/setsockopt
Since commit b66774b48dd9 ("Bluetooth: L2CAP: Fix UAF in channel timeout by holding conn ref")
l2cap_chan::conn has held reference and remains non-NULL also after the
corresponding hci_conn is deleted. In this state accessing various
fields eg. hci_conn::hdev is invalid, which leads to KASAN crash in
l2cap_sock_setsockopt() access of conn->hcon->hdev.
Check l2cap_chan::conn.hcon corresponds to an alive hci_conn before
trying to use it in l2cap_sock.c. Hold l2cap_chan_lock() in
getsockopt/setsockopt to ensure it stays alive, and to avoid data races
in l2cap_chan fields.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Thu, 17 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: access chan->conn safely in get/setsockopt Since commit b66774b48dd9 ("Bluetooth: L2CAP: Fix UAF in channel timeout by holding conn ref") l2cap_chan::conn has held reference and remains non-NULL also after the corresponding hci_conn is deleted. In this state accessing various fields eg. hci_conn::hdev is invalid, which leads to KASAN crash in l2cap_sock_setsockopt() access of conn->hcon->hdev. Check l2cap_chan::conn.hcon corresponds to an alive hci_conn before trying to use it in l2cap_sock.c. Hold l2cap_chan_lock() in getsockopt/setsockopt to ensure it stays alive, and to avoid data races in l2cap_chan fields. | |
| Title | Bluetooth: L2CAP: access chan->conn safely in get/setsockopt | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Projects
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-17T16:06:06.843Z
Reserved: 2026-09-11T19:38:34.786Z
Link: CVE-2026-90093
No data.
Status : Received
Published: 2026-09-17T17:17:00.900
Modified: 2026-09-17T17:17:00.900
Link: CVE-2026-90093
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.