kernel/include/net/bluetooth/hci_core.h, branch linux-6.18.y

Bluetooth: hci_core: lookup hci_conn on RX path on protocol side

2025-11-20T22:01:09Z

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) Fixes: 5af1f84ed13a ("Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync") Reported-by: syzbot+d32d77220b92eddd89ad@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d32d77220b92eddd89ad Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz

Bluetooth: btusb: mediatek: Fix kernel crash when releasing mtk iso interface

2025-11-20T21:51:14Z

When performing reset tests and encountering abnormal card drop issues that lead to a kernel crash, it is necessary to perform a null check before releasing resources to avoid attempting to release a null pointer. <4>[ 29.158070] Hardware name: Google Quigon sku196612/196613 board (DT) <4>[ 29.158076] Workqueue: hci0 hci_cmd_sync_work [bluetooth] <4>[ 29.158154] pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) <4>[ 29.158162] pc : klist_remove+0x90/0x158 <4>[ 29.158174] lr : klist_remove+0x88/0x158 <4>[ 29.158180] sp : ffffffc0846b3c00 <4>[ 29.158185] pmr_save: 000000e0 <4>[ 29.158188] x29: ffffffc0846b3c30 x28: ffffff80cd31f880 x27: ffffff80c1bdc058 <4>[ 29.158199] x26: dead000000000100 x25: ffffffdbdc624ea3 x24: ffffff80c1bdc4c0 <4>[ 29.158209] x23: ffffffdbdc62a3e6 x22: ffffff80c6c07000 x21: ffffffdbdc829290 <4>[ 29.158219] x20: 0000000000000000 x19: ffffff80cd3e0648 x18: 000000031ec97781 <4>[ 29.158229] x17: ffffff80c1bdc4a8 x16: ffffffdc10576548 x15: ffffff80c1180428 <4>[ 29.158238] x14: 0000000000000000 x13: 000000000000e380 x12: 0000000000000018 <4>[ 29.158248] x11: ffffff80c2a7fd10 x10: 0000000000000000 x9 : 0000000100000000 <4>[ 29.158257] x8 : 0000000000000000 x7 : 7f7f7f7f7f7f7f7f x6 : 2d7223ff6364626d <4>[ 29.158266] x5 : 0000008000000000 x4 : 0000000000000020 x3 : 2e7325006465636e <4>[ 29.158275] x2 : ffffffdc11afeff8 x1 : 0000000000000000 x0 : ffffffdc11be4d0c <4>[ 29.158285] Call trace: <4>[ 29.158290] klist_remove+0x90/0x158 <4>[ 29.158298] device_release_driver_internal+0x20c/0x268 <4>[ 29.158308] device_release_driver+0x1c/0x30 <4>[ 29.158316] usb_driver_release_interface+0x70/0x88 <4>[ 29.158325] btusb_mtk_release_iso_intf+0x68/0xd8 [btusb (HASH:e8b6 5)] <4>[ 29.158347] btusb_mtk_reset+0x5c/0x480 [btusb (HASH:e8b6 5)] <4>[ 29.158361] hci_cmd_sync_work+0x10c/0x188 [bluetooth (HASH:a4fa 6)] <4>[ 29.158430] process_scheduled_works+0x258/0x4e8 <4>[ 29.158441] worker_thread+0x300/0x428 <4>[ 29.158448] kthread+0x108/0x1d0 <4>[ 29.158455] ret_from_fork+0x10/0x20 <0>[ 29.158467] Code: 91343000 940139d1 f9400268 927ff914 (f9401297) <4>[ 29.158474] ---[ end trace 0000000000000000 ]--- <0>[ 29.167129] Kernel panic - not syncing: Oops: Fatal exception <2>[ 29.167144] SMP: stopping secondary CPUs <4>[ 29.167158] ------------[ cut here ]------------ Fixes: ceac1cb0259d ("Bluetooth: btusb: mediatek: add ISO data transmission functions") Signed-off-by: Chris Lu Signed-off-by: Luiz Augusto von Dentz

Bluetooth: hci_core: Fix tracking of periodic advertisement

2025-10-24T14:31:59Z

Periodic advertising enabled flag cannot be tracked by the enabled flag since advertising and periodic advertising each can be enabled/disabled separately from one another causing the states to be inconsistent when for example an advertising set is disabled its enabled flag is set to false which is then used for periodic which has not being disabled. Fixes: eca0ae4aea66 ("Bluetooth: Add initial implementation of BIS connections") Signed-off-by: Luiz Augusto von Dentz

Bluetooth: hci_core: Detect if an ISO link has stalled

2025-09-27T15:37:01Z

This attempts to detect if an ISO link has been waiting for an ISO buffer for longer than the maximum allowed transport latency then proceed to use hci_link_tx_to which prints an error and disconnects. Signed-off-by: Luiz Augusto von Dentz

Bluetooth: ISO: Use sk_sndtimeo as conn_timeout

2025-09-27T15:37:01Z

This aligns the usage of socket sk_sndtimeo as conn_timeout when initiating a connection and then use it when scheduling the resulting HCI command, similar to what has been done in bf98feea5b65 ("Bluetooth: hci_conn: Always use sk_timeo as conn_timeout"). Signed-off-by: Luiz Augusto von Dentz

Bluetooth: hci_event: Fix UAF in hci_acl_create_conn_sync

2025-09-20T15:01:10Z

This fixes the following UFA in hci_acl_create_conn_sync where a connection still pending is command submission (conn->state == BT_OPEN) maybe freed, also since this also can happen with the likes of hci_le_create_conn_sync fix it as well: BUG: KASAN: slab-use-after-free in hci_acl_create_conn_sync+0x5ef/0x790 net/bluetooth/hci_sync.c:6861 Write of size 2 at addr ffff88805ffcc038 by task kworker/u11:2/9541 CPU: 1 UID: 0 PID: 9541 Comm: kworker/u11:2 Not tainted 6.16.0-rc7 #3 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Workqueue: hci3 hci_cmd_sync_work Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x230 mm/kasan/report.c:480 kasan_report+0x118/0x150 mm/kasan/report.c:593 hci_acl_create_conn_sync+0x5ef/0x790 net/bluetooth/hci_sync.c:6861 hci_cmd_sync_work+0x210/0x3a0 net/bluetooth/hci_sync.c:332 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16-rc7/arch/x86/entry/entry_64.S:245 Allocated by task 123736: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] __hci_conn_add+0x233/0x1b30 net/bluetooth/hci_conn.c:939 hci_conn_add_unset net/bluetooth/hci_conn.c:1051 [inline] hci_connect_acl+0x16c/0x4e0 net/bluetooth/hci_conn.c:1634 pair_device+0x418/0xa70 net/bluetooth/mgmt.c:3556 hci_mgmt_cmd+0x9c9/0xef0 net/bluetooth/hci_sock.c:1719 hci_sock_sendmsg+0x6ca/0xef0 net/bluetooth/hci_sock.c:1839 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 sock_write_iter+0x258/0x330 net/socket.c:1131 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x54b/0xa90 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 103680: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 device_release+0x9c/0x1c0 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22b/0x480 lib/kobject.c:737 hci_conn_cleanup net/bluetooth/hci_conn.c:175 [inline] hci_conn_del+0x8ff/0xcb0 net/bluetooth/hci_conn.c:1173 hci_conn_complete_evt+0x3c7/0x1040 net/bluetooth/hci_event.c:3199 hci_event_func net/bluetooth/hci_event.c:7477 [inline] hci_event_packet+0x7e0/0x1200 net/bluetooth/hci_event.c:7531 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4070 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16-rc7/arch/x86/entry/entry_64.S:245 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 insert_work+0x3d/0x330 kernel/workqueue.c:2183 __queue_work+0xbd9/0xfe0 kernel/workqueue.c:2345 queue_delayed_work_on+0x18b/0x280 kernel/workqueue.c:2561 pairing_complete+0x1e7/0x2b0 net/bluetooth/mgmt.c:3451 pairing_complete_cb+0x1ac/0x230 net/bluetooth/mgmt.c:3487 hci_connect_cfm include/net/bluetooth/hci_core.h:2064 [inline] hci_conn_failed+0x24d/0x310 net/bluetooth/hci_conn.c:1275 hci_conn_complete_evt+0x3c7/0x1040 net/bluetooth/hci_event.c:3199 hci_event_func net/bluetooth/hci_event.c:7477 [inline] hci_event_packet+0x7e0/0x1200 net/bluetooth/hci_event.c:7531 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4070 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16-rc7/arch/x86/entry/entry_64.S:245 Fixes: aef2aa4fa98e ("Bluetooth: hci_event: Fix creating hci_conn object on error status") Reported-by: Junvyyang, Tencent Zhuque Lab Signed-off-by: Luiz Augusto von Dentz

Bluetooth: hci_core: Fix not accounting for BIS/CIS/PA links separately

2025-08-15T14:13:41Z

This fixes the likes of hci_conn_num(CIS_LINK) returning the total of ISO connection which includes BIS_LINK as well, so this splits the iso_num into each link type and introduces hci_iso_num that can be used in places where the total number of ISO connection still needs to be used. Fixes: 23205562ffc8 ("Bluetooth: separate CIS_LINK and BIS_LINK link types") Fixes: a7bcffc673de ("Bluetooth: Add PA_LINK to distinguish BIG sync and PA sync connections") Signed-off-by: Luiz Augusto von Dentz

Bluetooth: hci_core: Fix using ll_privacy_capable for current settings

2025-08-15T13:44:49Z

ll_privacy_capable only indicates that the controller supports the feature but it doesnt' check that LE is enabled so it end up being marked as active in the current settings when it shouldn't. Fixes: ad383c2c65a5 ("Bluetooth: hci_sync: Enable advertising when LL privacy is enabled") Signed-off-by: Luiz Augusto von Dentz

Bluetooth: hci_core: Fix using {cis,bis}_capable for current settings

2025-08-15T13:44:49Z

{cis,bis}_capable only indicates the controller supports the feature since it doesn't check that LE is enabled so it shall not be used for current setting, instead this introduces {cis,bis}_enabled macros that can be used to indicate that these features are currently enabled. Fixes: 26afbd826ee3 ("Bluetooth: Add initial implementation of CIS connections") Fixes: eca0ae4aea66 ("Bluetooth: Add initial implementation of BIS connections") Fixes: ae7533613133 ("Bluetooth: Check for ISO support in controller") Signed-off-by: Luiz Augusto von Dentz

Bluetooth: Add PA_LINK to distinguish BIG sync and PA sync connections

2025-07-23T14:35:14Z

Currently, BIS_LINK is used for both BIG sync and PA sync connections, which makes it impossible to distinguish them when searching for a PA sync connection. Adding PA_LINK will make the distinction clearer and simplify future extensions for PA-related features. Signed-off-by: Yang Li Signed-off-by: Luiz Augusto von Dentz