From d2841f22f4601a2d8bae64ccef7e8e5fa8499e2f Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 18 Sep 2018 19:10:48 -0700 Subject: [PATCH] wusb: Remove VLA usage of skcipher In the quest to remove all stack VLA usage from the kernel[1], this replaces struct crypto_skcipher and SKCIPHER_REQUEST_ON_STACK() usage with struct crypto_sync_skcipher and SYNC_SKCIPHER_REQUEST_ON_STACK(), which uses a fixed stack size. [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Cc: Greg Kroah-Hartman Cc: Felipe Balbi Cc: Johan Hovold Cc: "Gustavo A. R. Silva" Cc: linux-usb@vger.kernel.org Signed-off-by: Kees Cook Acked-by: Greg Kroah-Hartman Signed-off-by: Herbert Xu --- drivers/usb/wusbcore/crypto.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/usb/wusbcore/crypto.c b/drivers/usb/wusbcore/crypto.c index aff50eb09ca9..68ddee86a886 100644 --- a/drivers/usb/wusbcore/crypto.c +++ b/drivers/usb/wusbcore/crypto.c @@ -189,7 +189,7 @@ struct wusb_mac_scratch { * NOTE: blen is not aligned to a block size, we'll pad zeros, that's * what sg[4] is for. Maybe there is a smarter way to do this. */ -static int wusb_ccm_mac(struct crypto_skcipher *tfm_cbc, +static int wusb_ccm_mac(struct crypto_sync_skcipher *tfm_cbc, struct crypto_cipher *tfm_aes, struct wusb_mac_scratch *scratch, void *mic, @@ -198,7 +198,7 @@ static int wusb_ccm_mac(struct crypto_skcipher *tfm_cbc, size_t blen) { int result = 0; - SKCIPHER_REQUEST_ON_STACK(req, tfm_cbc); + SYNC_SKCIPHER_REQUEST_ON_STACK(req, tfm_cbc); struct scatterlist sg[4], sg_dst; void *dst_buf; size_t dst_size; @@ -224,7 +224,7 @@ static int wusb_ccm_mac(struct crypto_skcipher *tfm_cbc, if (!dst_buf) goto error_dst_buf; - iv = kzalloc(crypto_skcipher_ivsize(tfm_cbc), GFP_KERNEL); + iv = kzalloc(crypto_sync_skcipher_ivsize(tfm_cbc), GFP_KERNEL); if (!iv) goto error_iv; @@ -251,7 +251,7 @@ static int wusb_ccm_mac(struct crypto_skcipher *tfm_cbc, 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); + skcipher_request_set_sync_tfm(req, tfm_cbc); skcipher_request_set_callback(req, 0, NULL, NULL); skcipher_request_set_crypt(req, sg, &sg_dst, dst_size, iv); result = crypto_skcipher_encrypt(req); @@ -298,19 +298,19 @@ ssize_t wusb_prf(void *out, size_t out_size, { ssize_t result, bytes = 0, bitr; struct aes_ccm_nonce n = *_n; - struct crypto_skcipher *tfm_cbc; + struct crypto_sync_skcipher *tfm_cbc; struct crypto_cipher *tfm_aes; struct wusb_mac_scratch *scratch; u64 sfn = 0; __le64 sfn_le; - tfm_cbc = crypto_alloc_skcipher("cbc(aes)", 0, CRYPTO_ALG_ASYNC); + tfm_cbc = crypto_alloc_sync_skcipher("cbc(aes)", 0, 0); if (IS_ERR(tfm_cbc)) { result = PTR_ERR(tfm_cbc); printk(KERN_ERR "E: can't load CBC(AES): %d\n", (int)result); goto error_alloc_cbc; } - result = crypto_skcipher_setkey(tfm_cbc, key, 16); + result = crypto_sync_skcipher_setkey(tfm_cbc, key, 16); if (result < 0) { printk(KERN_ERR "E: can't set CBC key: %d\n", (int)result); goto error_setkey_cbc; @@ -351,7 +351,7 @@ ssize_t wusb_prf(void *out, size_t out_size, crypto_free_cipher(tfm_aes); error_alloc_aes: error_setkey_cbc: - crypto_free_skcipher(tfm_cbc); + crypto_free_sync_skcipher(tfm_cbc); error_alloc_cbc: return result; }