CVE-2026-64433

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> Bluetooth: MGMT: Fix UAF of hci_conn_params in add_device_complete<br /> <br /> add_device_complete() runs from the hci_cmd_sync_work kworker, which<br /> holds only hci_req_sync_lock and *not* hci_dev_lock. It calls<br /> hci_conn_params_lookup() and then dereferences the returned object<br /> (params-&gt;flags) without taking hci_dev_lock:<br /> <br /> params = hci_conn_params_lookup(hdev, &amp;cp-&gt;addr.bdaddr,<br /> le_addr_type(cp-&gt;addr.type));<br /> ...<br /> device_flags_changed(NULL, hdev, &amp;cp-&gt;addr.bdaddr,<br /> cp-&gt;addr.type, hdev-&gt;conn_flags,<br /> params ? params-&gt;flags : 0);<br /> <br /> hci_conn_params_lookup() walks hdev-&gt;le_conn_params and is documented to<br /> require hdev-&gt;lock. A concurrent MGMT_OP_REMOVE_DEVICE<br /> (remove_device()), which does run under hci_dev_lock, can call<br /> hci_conn_params_free() to list_del() and kfree() the very object the<br /> lookup returned, so the subsequent params-&gt;flags read touches freed<br /> memory [0].<br /> <br /> Hold hci_dev_lock() across the hci_conn_params_lookup() and the read of<br /> params-&gt;flags (and the matching event emission) so the lookup result<br /> cannot be freed by a concurrent remove_device() before it is used,<br /> honouring the locking contract of hci_conn_params_lookup().<br /> <br /> [0]: (trailing page/memory-state dump trimmed)<br /> BUG: KASAN: slab-use-after-free in add_device_complete+0x358/0x3d8 net/bluetooth/mgmt.c:7671<br /> Read of size 1 at addr ffff000017ab26c1 by task kworker/u9:8/388<br /> <br /> CPU: 1 UID: 0 PID: 388 Comm: kworker/u9:8 Not tainted 7.0.11 #20 PREEMPT<br /> Hardware name: linux,dummy-virt (DT)<br /> Workqueue: hci0 hci_cmd_sync_work<br /> Call trace:<br /> show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)<br /> __dump_stack lib/dump_stack.c:94 [inline]<br /> dump_stack_lvl+0xb4/0xd4 lib/dump_stack.c:120<br /> print_address_description mm/kasan/report.c:378 [inline]<br /> print_report+0x118/0x5d8 mm/kasan/report.c:482<br /> kasan_report+0xb0/0xf4 mm/kasan/report.c:595<br /> __asan_report_load1_noabort+0x20/0x2c mm/kasan/report_generic.c:378<br /> add_device_complete+0x358/0x3d8 net/bluetooth/mgmt.c:7671<br /> hci_cmd_sync_work+0x14c/0x240 net/bluetooth/hci_sync.c:334<br /> process_one_work+0x628/0xd38 kernel/workqueue.c:3289<br /> process_scheduled_works kernel/workqueue.c:3372 [inline]<br /> worker_thread+0x7a8/0xac0 kernel/workqueue.c:3453<br /> kthread+0x39c/0x444 kernel/kthread.c:436<br /> ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860<br /> <br /> Allocated by task 3401:<br /> kasan_save_stack+0x3c/0x64 mm/kasan/common.c:57<br /> kasan_save_track+0x20/0x3c mm/kasan/common.c:78<br /> kasan_save_alloc_info+0x40/0x54 mm/kasan/generic.c:570<br /> poison_kmalloc_redzone mm/kasan/common.c:398 [inline]<br /> __kasan_kmalloc+0xd4/0xd8 mm/kasan/common.c:415<br /> kasan_kmalloc include/linux/kasan.h:263 [inline]<br /> __kmalloc_cache_noprof+0x1b0/0x458 mm/slub.c:5385<br /> kmalloc_noprof include/linux/slab.h:950 [inline]<br /> kzalloc_noprof include/linux/slab.h:1188 [inline]<br /> hci_conn_params_add+0x10c/0x4b0 net/bluetooth/hci_core.c:2279<br /> hci_conn_params_set net/bluetooth/mgmt.c:5162 [inline]<br /> add_device+0x5b4/0xa54 net/bluetooth/mgmt.c:7755<br /> hci_mgmt_cmd net/bluetooth/hci_sock.c:1721 [inline]<br /> hci_sock_sendmsg+0x10b4/0x1dd0 net/bluetooth/hci_sock.c:1841<br /> sock_sendmsg_nosec net/socket.c:727 [inline]<br /> __sock_sendmsg+0xe0/0x128 net/socket.c:742<br /> sock_write_iter+0x250/0x390 net/socket.c:1195<br /> new_sync_write fs/read_write.c:595 [inline]<br /> vfs_write+0x66c/0xab0 fs/read_write.c:688<br /> ksys_write+0x1fc/0x24c fs/read_write.c:740<br /> __do_sys_write fs/read_write.c:751 [inline]<br /> __se_sys_write fs/read_write.c:748 [inline]<br /> __arm64_sys_write+0x70/0xa4 fs/read_write.c:748<br /> __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]<br /> invoke_syscall+0x84/0x2a8 arch/arm64/kernel/syscall.c:49<br /> el0_svc_common.constprop.0+0xe4/0x294 arch/arm64/kernel/syscall.c:132<br /> do_el0_svc+0x44/0x5c arch/arm64/kernel/syscall.c:151<br /> el0_svc+0x38/0xac arch/arm64/kernel/entry-common.c:724<br /> el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:743<br /> el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596<br /> <br /> Freed by task 3740:<br /> kasan_save_stack+0x3c/0x64 <br /> ---truncated---