From e4ff08a4d727146bb6717a39a8d399d834654345 Mon Sep 17 00:00:00 2001
From: Qiujun Huang <hqjagain@gmail.com>
Date: Sat, 4 Apr 2020 12:18:36 +0800
Subject: [PATCH] ath9k: Fix use-after-free Write in ath9k_htc_rx_msg
Git-commit: e4ff08a4d727146bb6717a39a8d399d834654345
Patch-mainline: v5.8-rc1
References: bsc#1111666
Write out of slab bounds. We should check epid.
The case reported by syzbot:
https://lore.kernel.org/linux-usb/0000000000006ac55b05a1c05d72@google.com
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@syzkaller.appspotmail.com
Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200404041838.10426-4-hqjagain@gmail.com
Acked-by: Takashi Iwai <tiwai@suse.de>
---
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 1bf63a4efb4c..d2e062eaf561 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];
--
2.16.4