From: Qiujun Huang <hqjagain@xxxxxxxxx> [ Upstream commit e4ff08a4d727146bb6717a39a8d399d834654345 ] Write out of slab bounds. We should check epid. The case reported by syzbot: https://lore.kernel.org/linux-usb/0000000000006ac55b05a1c05d72@xxxxxxxxxx BUG: KASAN: use-after-free in htc_process_conn_rsp drivers/net/wireless/ath/ath9k/htc_hst.c:131 [inline] BUG: KASAN: use-after-free in ath9k_htc_rx_msg+0xa25/0xaf0 drivers/net/wireless/ath/ath9k/htc_hst.c:443 Write of size 2 at addr ffff8881cea291f0 by task swapper/1/0 Call Trace: htc_process_conn_rsp drivers/net/wireless/ath/ath9k/htc_hst.c:131 [inline] ath9k_htc_rx_msg+0xa25/0xaf0 drivers/net/wireless/ath/ath9k/htc_hst.c:443 ath9k_hif_usb_reg_in_cb+0x1ba/0x630 drivers/net/wireless/ath/ath9k/hif_usb.c:718 __usb_hcd_giveback_urb+0x29a/0x550 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x368/0x420 drivers/usb/core/hcd.c:1716 dummy_timer+0x1258/0x32ae drivers/usb/gadget/udc/dummy_hcd.c:1966 call_timer_fn+0x195/0x6f0 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x5f9/0x1500 kernel/time/timer.c:1786 Reported-and-tested-by: syzbot+b1c61e5f11be5782f192@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Qiujun Huang <hqjagain@xxxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200404041838.10426-4-hqjagain@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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 d091c8ebdcf0..f705f0e1cb5b 100644 --- a/drivers/net/wireless/ath/ath9k/htc_hst.c +++ b/drivers/net/wireless/ath/ath9k/htc_hst.c @@ -113,6 +113,9 @@ static void htc_process_conn_rsp(struct htc_target *target, if (svc_rspmsg->status == HTC_SERVICE_SUCCESS) { epid = svc_rspmsg->endpoint_id; + if (epid < 0 || epid >= ENDPOINT_MAX) + return; + service_id = be16_to_cpu(svc_rspmsg->service_id); max_msglen = be16_to_cpu(svc_rspmsg->max_msg_len); endpoint = &target->endpoint[epid]; -- 2.25.1