From 620f1a632ebcc9811c2f8009ba52297c7006f805 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Tue, 13 Dec 2016 18:50:13 -0800 Subject: [PATCH] wusbcore: Fix one more crypto-on-the-stack bug 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. Use ZERO_PAGE instead. Cc: stable@vger.kernel.org # 4.9 only Reported-by: Eric Biggers Signed-off-by: Andy Lutomirski Signed-off-by: Greg Kroah-Hartman --- drivers/usb/wusbcore/crypto.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/usb/wusbcore/crypto.c b/drivers/usb/wusbcore/crypto.c index 79451f7ef1b7..062c205f0046 100644 --- a/drivers/usb/wusbcore/crypto.c +++ b/drivers/usb/wusbcore/crypto.c @@ -216,7 +216,6 @@ 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 }; u8 iv[crypto_skcipher_ivsize(tfm_cbc)]; size_t zero_padding; @@ -261,7 +260,7 @@ static int wusb_ccm_mac(struct crypto_skcipher *tfm_cbc, sg_set_buf(&sg[1], &scratch->b1, sizeof(scratch->b1)); sg_set_buf(&sg[2], b, blen); /* 0 if well behaved :) */ - sg_set_buf(&sg[3], bzero, zero_padding); + sg_set_page(&sg[3], ZERO_PAGE(0), zero_padding, 0); sg_init_one(&sg_dst, dst_buf, dst_size); skcipher_request_set_tfm(req, tfm_cbc); -- 2.20.1