[PATCH 4.9 49/62] rtlwifi: Fix potential overflow on P2P code

Greg Kroah-Hartman
2019-11-04T22:25:55Z

From: Laura Abbott <labbott@redhat.com>

commit 8c55dedb795be8ec0cf488f98c03a1c2176f7fb1 upstream.

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: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/net/wireless/realtek/rtlwifi/ps.c | 6 ++++++
1 file changed, 6 insertions(+)

--- a/drivers/net/wireless/realtek/rtlwifi/ps.c
+++ b/drivers/net/wireless/realtek/rtlwifi/ps.c
@@ -770,6 +770,9 @@ 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 ==
@@ -864,6 +867,9 @@ 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 ==