[PATCH 1/1] mwifiex: Fix possible buffer overflows in mwifiex_config_scan

From: Xiaohui Zhang
Date: Tue Dec 08 2020 - 10:12:22 EST


From: Zhang Xiaohui <ruc_zhangxiaohui@xxxxxxx>

mwifiex_config_scan() calls memcpy() without checking
the destination size may trigger a buffer overflower,
which a local user could use to cause denial of service
or the execution of arbitrary code.
Fix it by putting the length check before calling memcpy().

Signed-off-by: Zhang Xiaohui <ruc_zhangxiaohui@xxxxxxx>
---
drivers/net/wireless/marvell/mwifiex/scan.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/marvell/mwifiex/scan.c b/drivers/net/wireless/marvell/mwifiex/scan.c
index c2a685f63..34293fd80 100644
--- a/drivers/net/wireless/marvell/mwifiex/scan.c
+++ b/drivers/net/wireless/marvell/mwifiex/scan.c
@@ -931,7 +931,7 @@ mwifiex_config_scan(struct mwifiex_private *priv,
wildcard_ssid_tlv->max_ssid_length = 0xfe;

memcpy(wildcard_ssid_tlv->ssid,
- user_scan_in->ssid_list[i].ssid, ssid_len);
+ user_scan_in->ssid_list[i].ssid, min_t(u32, ssid_len, 1));

tlv_pos += (sizeof(wildcard_ssid_tlv->header)
+ le16_to_cpu(wildcard_ssid_tlv->header.len));
--
2.17.1