Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_core: lookup hci_conn on RX path on protocol side The hdev lock/lookup/unlock/use pattern in the packet RX path doesn't ensure hci_conn* is not concurrently modified/deleted. This locking appears to be leftover from before conn_hash started using RCU commit bf4c63252490b ("Bluetooth: convert conn hash to RCU") and not clear if it had purpose since then. Currently, there are code paths that delete hci_conn* from elsewhere than the ordered hdev->workqueue where the RX work runs in. E.g. commit 5af1f84ed13a ("Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync") introduced some of these, and there probably were a few others before it. It's better to do the locking so that even if these run concurrently no UAF is possible. Move the lookup of hci_conn and associated socket-specific conn to protocol recv handlers, and do them within a single critical section to cover hci_conn* usage and lookup. syzkaller has reported a crash that appears to be this issue: [Task hdev->workqueue] [Task 2] hci_disconnect_all_sync l2cap_recv_acldata(hcon) hci_conn_get(hcon) hci_abort_conn_sync(hcon) hci_dev_lock hci_dev_lock hci_conn_del(hcon) v-------------------------------- hci_dev_unlock hci_conn_put(hcon) conn = hcon->l2cap_data (UAF)
Product status
5af1f84ed13a416297ab9ced7537f4d5ae7f329a (git) before ec74cdf77310c43b01b83ee898a9bd4b4b0b8e93
5af1f84ed13a416297ab9ced7537f4d5ae7f329a (git) before 79a2d4678ba90bdba577dc3af88cc900d6dcd5ee
cd55c13bbb3d093ae601aa97e588ed4c1390ebb1 (git)
4d3ca4a9aaf0aa798a6be372dc0fc3a29e37dd57 (git)
80265dd1d944c3f33e52375b5dbe654980bd2688 (git)
6.6
Any version before 6.6
6.17.11 (semver)
6.18 (original_commit_for_fix)
References
git.kernel.org/...c/ec74cdf77310c43b01b83ee898a9bd4b4b0b8e93
git.kernel.org/...c/79a2d4678ba90bdba577dc3af88cc900d6dcd5ee
Data based on CVE®. Copyright © 1999-2025, The MITRE Corporation. All rights reserved.
