| Message ID | 20230304135035.6232-1-lm0963hack@gmail.com (mailing list archive) |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [v2,1/1] Bluetooth: fix race condition in hci_cmd_sync_clear | expand |
Hello: This patch was applied to bluetooth/bluetooth-next.git (master) by Luiz Augusto von Dentz <luiz.von.dentz@intel.com>: On Sat, 4 Mar 2023 21:50:35 +0800 you wrote: > There is a potential race condition in hci_cmd_sync_work and > hci_cmd_sync_clear, and could lead to use-after-free. For instance, > hci_cmd_sync_work is added to the 'req_workqueue' after cancel_work_sync > The entry of 'cmd_sync_work_list' may be freed in hci_cmd_sync_clear, and > causing kernel panic when it is used in 'hci_cmd_sync_work'. > > Here's the call trace: > > [...] Here is the summary with links: - [v2,1/1] Bluetooth: fix race condition in hci_cmd_sync_clear https://git.kernel.org/bluetooth/bluetooth-next/c/83ce39248d6d You are awesome, thank you!
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 117eedb6f709..3103daf49d63 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -643,6 +643,7 @@ void hci_cmd_sync_clear(struct hci_dev *hdev) cancel_work_sync(&hdev->cmd_sync_work); cancel_work_sync(&hdev->reenable_adv_work); + mutex_lock(&hdev->cmd_sync_work_lock); list_for_each_entry_safe(entry, tmp, &hdev->cmd_sync_work_list, list) { if (entry->destroy) entry->destroy(hdev, entry->data, -ECANCELED); @@ -650,6 +651,7 @@ void hci_cmd_sync_clear(struct hci_dev *hdev) list_del(&entry->list); kfree(entry); } + mutex_unlock(&hdev->cmd_sync_work_lock); } void __hci_cmd_sync_cancel(struct hci_dev *hdev, int err)
There is a potential race condition in hci_cmd_sync_work and hci_cmd_sync_clear, and could lead to use-after-free. For instance, hci_cmd_sync_work is added to the 'req_workqueue' after cancel_work_sync The entry of 'cmd_sync_work_list' may be freed in hci_cmd_sync_clear, and causing kernel panic when it is used in 'hci_cmd_sync_work'. Here's the call trace: dump_stack_lvl+0x49/0x63 print_report.cold+0x5e/0x5d3 ? hci_cmd_sync_work+0x282/0x320 kasan_report+0xaa/0x120 ? hci_cmd_sync_work+0x282/0x320 __asan_report_load8_noabort+0x14/0x20 hci_cmd_sync_work+0x282/0x320 process_one_work+0x77b/0x11c0 ? _raw_spin_lock_irq+0x8e/0xf0 worker_thread+0x544/0x1180 ? poll_idle+0x1e0/0x1e0 kthread+0x285/0x320 ? process_one_work+0x11c0/0x11c0 ? kthread_complete_and_exit+0x30/0x30 ret_from_fork+0x22/0x30 </TASK> Allocated by task 266: kasan_save_stack+0x26/0x50 __kasan_kmalloc+0xae/0xe0 kmem_cache_alloc_trace+0x191/0x350 hci_cmd_sync_queue+0x97/0x2b0 hci_update_passive_scan+0x176/0x1d0 le_conn_complete_evt+0x1b5/0x1a00 hci_le_conn_complete_evt+0x234/0x340 hci_le_meta_evt+0x231/0x4e0 hci_event_packet+0x4c5/0xf00 hci_rx_work+0x37d/0x880 process_one_work+0x77b/0x11c0 worker_thread+0x544/0x1180 kthread+0x285/0x320 ret_from_fork+0x22/0x30 Freed by task 269: kasan_save_stack+0x26/0x50 kasan_set_track+0x25/0x40 kasan_set_free_info+0x24/0x40 ____kasan_slab_free+0x176/0x1c0 __kasan_slab_free+0x12/0x20 slab_free_freelist_hook+0x95/0x1a0 kfree+0xba/0x2f0 hci_cmd_sync_clear+0x14c/0x210 hci_unregister_dev+0xff/0x440 vhci_release+0x7b/0xf0 __fput+0x1f3/0x970 ____fput+0xe/0x20 task_work_run+0xd4/0x160 do_exit+0x8b0/0x22a0 do_group_exit+0xba/0x2a0 get_signal+0x1e4a/0x25b0 arch_do_signal_or_restart+0x93/0x1f80 exit_to_user_mode_prepare+0xf5/0x1a0 syscall_exit_to_user_mode+0x26/0x50 ret_from_fork+0x15/0x30 v2: - Fixed code style issues Signed-off-by: Min Li <lm0963hack@gmail.com> --- net/bluetooth/hci_sync.c | 2 ++ 1 file changed, 2 insertions(+)