From: Laura Abbott <labbott@redhat.com>
Date: Fri, 18 Oct 2019 07:43:21 -0400
Subject: [PATCH] rtlwifi: Fix potential overflow on P2P code
Git-commit: 8c55dedb795be8ec0cf488f98c03a1c2176f7fb1
Patch-mainline: v5.4-rc6
References: bsc#1154372 CVE-2019-17666

Nicolas Waisman noticed that even though noa_len is checked for
a compatible length it's still possible to overrun the buffers
of p2pinfo since there's no check on the upper bound of noa_num.
Bound noa_num against P2P_MAX_NOA_NUM.

Reported-by: Nicolas Waisman <nico@semmle.com>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Cho, Yu-Chen <acho@suse.com>
---
 drivers/net/wireless/realtek/rtlwifi/ps.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/net/wireless/realtek/rtlwifi/ps.c
+++ b/drivers/net/wireless/realtek/rtlwifi/ps.c
@@ -772,6 +772,8 @@ static void rtl_p2p_noa_ie(struct ieee80
 				return;
 			} else {
 				noa_num = (noa_len - 2) / 13;
+				if (noa_num > P2P_MAX_NOA_NUM)
+					noa_num = P2P_MAX_NOA_NUM;
 			}
 			noa_index = ie[3];
 			if (rtlpriv->psc.p2p_ps_info.p2p_ps_mode ==
@@ -866,6 +868,8 @@ static void rtl_p2p_action_ie(struct iee
 				return;
 			} else {
 				noa_num = (noa_len - 2) / 13;
+				if (noa_num > P2P_MAX_NOA_NUM)
+					noa_num = P2P_MAX_NOA_NUM;
 			}
 			noa_index = ie[3];
 			if (rtlpriv->psc.p2p_ps_info.p2p_ps_mode ==