From acf91ec384dd4c7c2c88cbaa2e0374e537123c1f Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Thu, 22 Sep 2016 11:20:42 -0700 Subject: [PATCH] Bluetooth: btwilink: Save the packet type before sending Running with KASAN produces some messages: BUG: KASAN: use-after-free in ti_st_send_frame+0x9c/0x16c at addr ffffffc064868fe8 Read of size 1 by task kworker/u17:1/1266 Hardware name: HiKey Development Board (DT) Workqueue: hci0 hci_cmd_work Call trace: [] dump_backtrace+0x0/0x178 [] show_stack+0x20/0x28 [] dump_stack+0xa8/0xe0 [] print_trailer+0x110/0x174 [] object_err+0x4c/0x5c [] kasan_report_error+0x254/0x54c [] kasan_report+0x64/0x70 [] __asan_load1+0x4c/0x54 [] ti_st_send_frame+0x9c/0x16c [] hci_send_frame+0xb4/0x118 [] hci_cmd_work+0xcc/0x154 [] process_one_work+0x26c/0x7a4 [] worker_thread+0x9c/0x73c [] kthread+0x138/0x154 [] ret_from_fork+0x10/0x40 The packet is being accessed for statistics after it has been freed. Save the packet type before sending for statistics afterwards. Signed-off-by: Laura Abbott Signed-off-by: Marcel Holtmann --- drivers/bluetooth/btwilink.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/bluetooth/btwilink.c b/drivers/bluetooth/btwilink.c index 485281b3f167..ef51c9c864c5 100644 --- a/drivers/bluetooth/btwilink.c +++ b/drivers/bluetooth/btwilink.c @@ -245,6 +245,7 @@ static int ti_st_send_frame(struct hci_dev *hdev, struct sk_buff *skb) { struct ti_st *hst; long len; + int pkt_type; hst = hci_get_drvdata(hdev); @@ -258,6 +259,7 @@ static int ti_st_send_frame(struct hci_dev *hdev, struct sk_buff *skb) * Freeing skb memory is taken care in shared transport layer, * so don't free skb memory here. */ + pkt_type = hci_skb_pkt_type(skb); len = hst->st_write(skb); if (len < 0) { kfree_skb(skb); @@ -268,7 +270,7 @@ static int ti_st_send_frame(struct hci_dev *hdev, struct sk_buff *skb) /* ST accepted our skb. So, Go ahead and do rest */ hdev->stat.byte_tx += len; - ti_st_tx_complete(hst, hci_skb_pkt_type(skb)); + ti_st_tx_complete(hst, pkt_type); return 0; } -- 2.20.1