From: Fedor Pchelkin <pchelkin@xxxxxxxxx> [ Upstream commit 061b0cb9327b80d7a0f63a33e7c3e2a91a71f142 ] A bad USB device is able to construct a service connection response message with target endpoint being ENDPOINT0 which is reserved for HTC_CTRL_RSVD_SVC and should not be modified to be used for any other services. Reject such service connection responses. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.") Reported-by: syzbot+b68fbebe56d8362907e8@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx> Acked-by: Toke Høiland-Jørgensen <toke@xxxxxxx> Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20230516150427.79469-1-pchelkin@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/wireless/ath/ath9k/htc_hst.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath9k/htc_hst.c b/drivers/net/wireless/ath/ath9k/htc_hst.c index fe62ff668f757..99667aba289df 100644 --- a/drivers/net/wireless/ath/ath9k/htc_hst.c +++ b/drivers/net/wireless/ath/ath9k/htc_hst.c @@ -114,7 +114,13 @@ 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) + + /* Check that the received epid for the endpoint to attach + * a new service is valid. ENDPOINT0 can't be used here as it + * is already reserved for HTC_CTRL_RSVD_SVC service and thus + * should not be modified. + */ + if (epid <= ENDPOINT0 || epid >= ENDPOINT_MAX) return; service_id = be16_to_cpu(svc_rspmsg->service_id); -- 2.39.2