From: Archie Pusaka apusaka@chromium.org
stable inclusion from linux-4.19.191 commit 75e26178e26f910f7f26c79c2824b726eecf0dfb CVE: CVE-2021-33033
--------------------------------
commit 5c4c8c9544099bb9043a10a5318130a943e32fc3 upstream.
hci_chan can be created in 2 places: hci_loglink_complete_evt() if it is an AMP hci_chan, or l2cap_conn_add() otherwise. In theory, Only AMP hci_chan should be removed by a call to hci_disconn_loglink_complete_evt(). However, the controller might mess up, call that function, and destroy an hci_chan which is not initiated by hci_loglink_complete_evt().
This patch adds a verification that the destroyed hci_chan must have been init'd by hci_loglink_complete_evt().
Example crash call trace: Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xe3/0x144 lib/dump_stack.c:118 print_address_description+0x67/0x22a mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report+0x251/0x28f mm/kasan/report.c:396 hci_send_acl+0x3b/0x56e net/bluetooth/hci_core.c:4072 l2cap_send_cmd+0x5af/0x5c2 net/bluetooth/l2cap_core.c:877 l2cap_send_move_chan_cfm_icid+0x8e/0xb1 net/bluetooth/l2cap_core.c:4661 l2cap_move_fail net/bluetooth/l2cap_core.c:5146 [inline] l2cap_move_channel_rsp net/bluetooth/l2cap_core.c:5185 [inline] l2cap_bredr_sig_cmd net/bluetooth/l2cap_core.c:5464 [inline] l2cap_sig_channel net/bluetooth/l2cap_core.c:5799 [inline] l2cap_recv_frame+0x1d12/0x51aa net/bluetooth/l2cap_core.c:7023 l2cap_recv_acldata+0x2ea/0x693 net/bluetooth/l2cap_core.c:7596 hci_acldata_packet net/bluetooth/hci_core.c:4606 [inline] hci_rx_work+0x2bd/0x45e net/bluetooth/hci_core.c:4796 process_one_work+0x6f8/0xb50 kernel/workqueue.c:2175 worker_thread+0x4fc/0x670 kernel/workqueue.c:2321 kthread+0x2f0/0x304 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415
Allocated by task 38: set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0x8d/0x9a mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x102/0x129 mm/slub.c:2787 kmalloc include/linux/slab.h:515 [inline] kzalloc include/linux/slab.h:709 [inline] hci_chan_create+0x86/0x26d net/bluetooth/hci_conn.c:1674 l2cap_conn_add.part.0+0x1c/0x814 net/bluetooth/l2cap_core.c:7062 l2cap_conn_add net/bluetooth/l2cap_core.c:7059 [inline] l2cap_connect_cfm+0x134/0x852 net/bluetooth/l2cap_core.c:7381 hci_connect_cfm+0x9d/0x122 include/net/bluetooth/hci_core.h:1404 hci_remote_ext_features_evt net/bluetooth/hci_event.c:4161 [inline] hci_event_packet+0x463f/0x72fa net/bluetooth/hci_event.c:5981 hci_rx_work+0x197/0x45e net/bluetooth/hci_core.c:4791 process_one_work+0x6f8/0xb50 kernel/workqueue.c:2175 worker_thread+0x4fc/0x670 kernel/workqueue.c:2321 kthread+0x2f0/0x304 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415
Freed by task 1732: set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free mm/kasan/kasan.c:521 [inline] __kasan_slab_free+0x106/0x128 mm/kasan/kasan.c:493 slab_free_hook mm/slub.c:1409 [inline] slab_free_freelist_hook+0xaa/0xf6 mm/slub.c:1436 slab_free mm/slub.c:3009 [inline] kfree+0x182/0x21e mm/slub.c:3972 hci_disconn_loglink_complete_evt net/bluetooth/hci_event.c:4891 [inline] hci_event_packet+0x6a1c/0x72fa net/bluetooth/hci_event.c:6050 hci_rx_work+0x197/0x45e net/bluetooth/hci_core.c:4791 process_one_work+0x6f8/0xb50 kernel/workqueue.c:2175 worker_thread+0x4fc/0x670 kernel/workqueue.c:2321 kthread+0x2f0/0x304 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415
The buggy address belongs to the object at ffff8881d7af9180 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 24 bytes inside of 128-byte region [ffff8881d7af9180, ffff8881d7af9200) The buggy address belongs to the page: page:ffffea00075ebe40 count:1 mapcount:0 mapping:ffff8881da403200 index:0x0 flags: 0x8000000000000200(slab) raw: 8000000000000200 dead000000000100 dead000000000200 ffff8881da403200 raw: 0000000000000000 0000000080150015 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected
Memory state around the buggy address: ffff8881d7af9080: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8881d7af9100: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff8881d7af9180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^ ffff8881d7af9200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881d7af9280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
Signed-off-by: Archie Pusaka apusaka@chromium.org Reported-by: syzbot+98228e7407314d2d4ba2@syzkaller.appspotmail.com Reviewed-by: Alain Michaud alainm@chromium.org Reviewed-by: Abhishek Pandit-Subedi abhishekpandit@chromium.org Signed-off-by: Marcel Holtmann marcel@holtmann.org Cc: George Kennedy george.kennedy@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com Reviewed-by: Xiu Jianfeng xiujianfeng@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- include/net/bluetooth/hci_core.h | 1 + net/bluetooth/hci_event.c | 3 ++- 2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index cc2d0c3b475b5..d8ea8b5ab3572 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -526,6 +526,7 @@ struct hci_chan { struct sk_buff_head data_q; unsigned int sent; __u8 state; + bool amp; };
struct hci_conn_params { diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 3ca5416d6442f..b7c87f505fb6d 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -4719,6 +4719,7 @@ static void hci_loglink_complete_evt(struct hci_dev *hdev, struct sk_buff *skb) return;
hchan->handle = le16_to_cpu(ev->handle); + hchan->amp = true;
BT_DBG("hcon %p mgr %p hchan %p", hcon, hcon->amp_mgr, hchan);
@@ -4751,7 +4752,7 @@ static void hci_disconn_loglink_complete_evt(struct hci_dev *hdev, hci_dev_lock(hdev);
hchan = hci_chan_lookup_handle(hdev, le16_to_cpu(ev->handle)); - if (!hchan) + if (!hchan || !hchan->amp) goto unlock;
amp_destroy_logical_link(hchan, ev->reason);