Syzbot has reported the following UBSAN splat: UBSAN: array-index-out-of-bounds in drivers/net/wireless/ath/ath9k/htc_hst.c:26:35 index 255 is out of range for type 'struct htc_endpoint[22]' ... Call Trace: ... __ubsan_handle_out_of_bounds+0x115/0x140 htc_send_epid+0x1e0/0x2d0 ath9k_wmi_cmd+0x31f/0x590 ath9k_regread+0xdc/0x140 ? __pfx_ath9k_regread+0x10/0x10 ? _raw_spin_unlock_irqrestore+0xae/0x110 ? __pfx__raw_spin_unlock_irqrestore+0x10/0x10 ? __pfx_ath9k_regread+0x10/0x10 ath9k_hw_init+0x4b0/0x2230 ? init_timer_key+0x171/0x2d0 ath9k_htc_probe_device+0xa66/0x1fe0 ? __pfx_ath9k_htc_probe_device+0x10/0x10 ? usb_hcd_submit_urb+0x345/0x1ae0 ? usb_free_urb+0x9d/0x120 ? ath9k_hif_usb_alloc_urbs+0x1077/0x1150 ath9k_htc_hw_init+0x32/0x70 ath9k_hif_usb_firmware_cb+0x240/0x4c0 ? __pfx_ath9k_hif_usb_firmware_cb+0x10/0x10 request_firmware_work_func+0x106/0x1c0 ... IIUC https://syzkaller.appspot.com/text?tag=ReproC&x=1734b9f1180000 makes an attempt to emulate ath9k USB device in somewhat weird and obscure way so I'm not sure whether this may happen on a real hardware. OTOH whether ending with ENDPOINT_UNUSED in 'htc_connect_service()' may indicate the malfunctioned real device, it may be better to reject such a device with -ENODEV. Reported-by: syzbot+93cbd5fbb85814306ba1@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=93cbd5fbb85814306ba1 Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.") Signed-off-by: Dmitry Antipov <dmantipov@xxxxxxxxx> --- v2: avoid conditional expression (Kalle) and return -ENODEV without touching *conn_rsp_epid (Toke) --- drivers/net/wireless/ath/ath9k/htc_hst.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/wireless/ath/ath9k/htc_hst.c b/drivers/net/wireless/ath/ath9k/htc_hst.c index eb631fd3336d..a5bc0a5dfe7c 100644 --- a/drivers/net/wireless/ath/ath9k/htc_hst.c +++ b/drivers/net/wireless/ath/ath9k/htc_hst.c @@ -294,6 +294,9 @@ int htc_connect_service(struct htc_target *target, return -ETIMEDOUT; } + if (unlikely(target->conn_rsp_epid == ENDPOINT_UNUSED)) + return -ENODEV; + *conn_rsp_epid = target->conn_rsp_epid; return 0; err: -- 2.47.0
