[PATCH AUTOSEL 4.19 204/237] wireless: airo: potential buffer overflow in sprintf()

Sasha Levin
2019-11-16T15:47:19Z

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit 3d39e1bb1c88f32820c5f9271f2c8c2fb9a52bac ]

It looks like we wanted to print a maximum of BSSList_rid.ssidLen bytes
of the ssid, but we accidentally use "%*s" (width) instead of "%.*s"
(precision) so if the ssid doesn't have a NUL terminator this could lead
to an overflow.

Static analysis. Not tested.

Fixes: e174961ca1a0 ("net: convert print_mac to %pM")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/cisco/airo.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/cisco/airo.c b/drivers/net/wireless/cisco/airo.c
index 04dd7a9365938..5512c7f73fce8 100644
--- a/drivers/net/wireless/cisco/airo.c
+++ b/drivers/net/wireless/cisco/airo.c
@@ -5462,7 +5462,7 @@ static int proc_BSSList_open( struct inode *inode, struct file *file ) {
we have to add a spin lock... */
rc = readBSSListRid(ai, doLoseSync, &BSSList_rid);
while(rc == 0 && BSSList_rid.index != cpu_to_le16(0xffff)) {
- ptr += sprintf(ptr, "%pM %*s rssi = %d",
+ ptr += sprintf(ptr, "%pM %.*s rssi = %d",
BSSList_rid.bssid,
(int)BSSList_rid.ssidLen,
BSSList_rid.ssid,
--
2.20.1