[PATCH] wusbcore: Fix one more crypto-on-the-stack bug

From: Andy Lutomirski
Date: Mon Dec 12 2016 - 15:52:55 EST


The driver put a constant buffer of all zeros on the stack and
pointed a scatterlist entry at it. This doesn't work with virtual
stacks. Make the buffer static to fix it.

Cc: stable@xxxxxxxxxxxxxxx # 4.9 only
Reported-by: Eric Biggers <ebiggers3@xxxxxxxxx>
Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
---
drivers/usb/wusbcore/crypto.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/wusbcore/crypto.c b/drivers/usb/wusbcore/crypto.c
index 79451f7ef1b7..a7e007a0cd49 100644
--- a/drivers/usb/wusbcore/crypto.c
+++ b/drivers/usb/wusbcore/crypto.c
@@ -216,7 +216,7 @@ static int wusb_ccm_mac(struct crypto_skcipher *tfm_cbc,
struct scatterlist sg[4], sg_dst;
void *dst_buf;
size_t dst_size;
- const u8 bzero[16] = { 0 };
+ static const u8 bzero[16] = { 0 };
u8 iv[crypto_skcipher_ivsize(tfm_cbc)];
size_t zero_padding;

--
2.9.3