From: Lee Gibson <leegib@gmail.com>
Date: Wed, 28 Apr 2021 11:55:08 +0000 (+0100)
Subject: wl1251: Fix possible buffer overflow in wl1251_cmd_scan
X-Git-Tag: v5.12.18~148
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=302e2ee34c5f7c5d805b7f835d9a6f2b43474e2a;p=thirdparty%2Fkernel%2Fstable.git

wl1251: Fix possible buffer overflow in wl1251_cmd_scan

[ Upstream commit d10a87a3535cce2b890897914f5d0d83df669c63 ]

Function wl1251_cmd_scan calls memcpy without checking the length.
Harden by checking the length is within the maximum allowed size.

Signed-off-by: Lee Gibson <leegib@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210428115508.25624-1-leegib@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/net/wireless/ti/wl1251/cmd.c b/drivers/net/wireless/ti/wl1251/cmd.c
index 498c8db2eb48b..d7a869106782f 100644
--- a/drivers/net/wireless/ti/wl1251/cmd.c
+++ b/drivers/net/wireless/ti/wl1251/cmd.c
@@ -454,9 +454,12 @@ int wl1251_cmd_scan(struct wl1251 *wl, u8 *ssid, size_t ssid_len,
 		cmd->channels[i].channel = channels[i]->hw_value;
 	}
 
-	cmd->params.ssid_len = ssid_len;
-	if (ssid)
-		memcpy(cmd->params.ssid, ssid, ssid_len);
+	if (ssid) {
+		int len = clamp_val(ssid_len, 0, IEEE80211_MAX_SSID_LEN);
+
+		cmd->params.ssid_len = len;
+		memcpy(cmd->params.ssid, ssid, len);
+	}
 
 	ret = wl1251_cmd_send(wl, CMD_SCAN, cmd, sizeof(*cmd));
 	if (ret < 0) {