Bluetooth: hci_sync: free the advertising instance on the failure and cancel paths

Summary

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: free the advertising instance on the failure and cancel paths adv_timeout_expire() hands a kmalloc()ed instance byte to hci_cmd_sync_queue() with a NULL destroy callback, and only adv_timeout_expire_sync() frees it. That leaks on two paths: • the return value is not checked, and hci_cmd_sync_queue() does not take ownership when it fails (-ENETDOWN, -ENODEV, -ENOMEM); • a cancelled entry is not released, as _hci_cmd_sync_cancel_entry() does not free entry->data when there is no destroy callback. hci_cmd_sync_clear() cancels every pending entry when the controller is unregistered. Free the buffer from a destroy callback, and in the caller when the entry could not be queued at all.

Timeline

1. Sep 17, 2026, 4:07 PM UTCCVE published
2. Oct 19, 2026, 9:00 AM UTCRecord last updated

Affected versions

• Linux Linux

  From c249ea9b4309cf3250c5bbb42a05d38d0ed9071c · fixed in c2019224a766245b7db39d87fdfe84c3fdc879d9; From c249ea9b4309cf3250c5bbb42a05d38d0ed9071c · fixed in 193182c6467f508a8a61d5db506d796ffed6eee6; From c249ea9b4309cf3250c5bbb42a05d38d0ed9071c · fixed in 2e3d827cd56865c14f6ca118bbccd7801091fb21; From c249ea9b4309cf3250c5bbb42a05d38d0ed9071c · fixed in 9c3b6c1413bd0b4993642d987616331f84d9b7f5; From c249ea9b4309cf3250c5bbb42a05d38d0ed9071c · fixed in bb5ca1cc7744c41c59002bd6523714a685ae6595; From c249ea9b4309cf3250c5bbb42a05d38d0ed9071c · fixed in 120d8dc042e3d45073bb6e50ee7b058a0b182627

• Linux Linux

  6.1

• KernelLinux

  From 6.1.0 · fixed in 6.1.188; From 6.2.0 · fixed in 6.6.157; From 6.7.0 · fixed in 6.12.110; From 6.13.0 · fixed in 6.18.52; From 6.19.0 · fixed in 7.2.6

References 6