From 06deeec77a5a689cc94b21a8a91a76e42176685d Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Mon, 12 Dec 2016 12:54:37 -0800 Subject: [PATCH] cifs: Fix smbencrypt() to stop pointing a scatterlist at the stack smbencrypt() points a scatterlist to the stack, which is breaks if CONFIG_VMAP_STACK=y. Fix it by switching to crypto_cipher_encrypt_one(). The new code should be considerably faster as an added benefit. This code is nearly identical to some code that Eric Biggers suggested. Cc: stable@vger.kernel.org # 4.9 only Reported-by: Eric Biggers Signed-off-by: Andy Lutomirski Acked-by: Jeff Layton Signed-off-by: Steve French --- fs/cifs/smbencrypt.c | 40 ++++++++-------------------------------- 1 file changed, 8 insertions(+), 32 deletions(-) diff --git a/fs/cifs/smbencrypt.c b/fs/cifs/smbencrypt.c index 699b7868108f..c12bffefa3c9 100644 --- a/fs/cifs/smbencrypt.c +++ b/fs/cifs/smbencrypt.c @@ -23,7 +23,7 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ -#include +#include #include #include #include @@ -69,46 +69,22 @@ str_to_key(unsigned char *str, unsigned char *key) static int smbhash(unsigned char *out, const unsigned char *in, unsigned char *key) { - int rc; unsigned char key2[8]; - struct crypto_skcipher *tfm_des; - struct scatterlist sgin, sgout; - struct skcipher_request *req; + struct crypto_cipher *tfm_des; str_to_key(key, key2); - tfm_des = crypto_alloc_skcipher("ecb(des)", 0, CRYPTO_ALG_ASYNC); + tfm_des = crypto_alloc_cipher("des", 0, 0); if (IS_ERR(tfm_des)) { - rc = PTR_ERR(tfm_des); cifs_dbg(VFS, "could not allocate des crypto API\n"); - goto smbhash_err; + return PTR_ERR(tfm_des); } - req = skcipher_request_alloc(tfm_des, GFP_KERNEL); - if (!req) { - rc = -ENOMEM; - cifs_dbg(VFS, "could not allocate des crypto API\n"); - goto smbhash_free_skcipher; - } + crypto_cipher_setkey(tfm_des, key2, 8); + crypto_cipher_encrypt_one(tfm_des, out, in); + crypto_free_cipher(tfm_des); - crypto_skcipher_setkey(tfm_des, key2, 8); - - sg_init_one(&sgin, in, 8); - sg_init_one(&sgout, out, 8); - - skcipher_request_set_callback(req, 0, NULL, NULL); - skcipher_request_set_crypt(req, &sgin, &sgout, 8, NULL); - - rc = crypto_skcipher_encrypt(req); - if (rc) - cifs_dbg(VFS, "could not encrypt crypt key rc: %d\n", rc); - - skcipher_request_free(req); - -smbhash_free_skcipher: - crypto_free_skcipher(tfm_des); -smbhash_err: - return rc; + return 0; } static int