From dc568baf9bd1d455de81a18bb68d555a3a9edc3f Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 18 Sep 2018 19:10:44 -0700 Subject: [PATCH] block: cryptoloop: 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: Jens Axboe Cc: linux-block@vger.kernel.org Signed-off-by: Kees Cook Acked-by: Ard Biesheuvel Signed-off-by: Herbert Xu --- drivers/block/cryptoloop.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/drivers/block/cryptoloop.c b/drivers/block/cryptoloop.c index 7033a4beda66..254ee7d54e91 100644 --- a/drivers/block/cryptoloop.c +++ b/drivers/block/cryptoloop.c @@ -45,7 +45,7 @@ cryptoloop_init(struct loop_device *lo, const struct loop_info64 *info) char cms[LO_NAME_SIZE]; /* cipher-mode string */ char *mode; char *cmsp = cms; /* c-m string pointer */ - struct crypto_skcipher *tfm; + struct crypto_sync_skcipher *tfm; /* encryption breaks for non sector aligned offsets */ @@ -80,13 +80,13 @@ cryptoloop_init(struct loop_device *lo, const struct loop_info64 *info) *cmsp++ = ')'; *cmsp = 0; - tfm = crypto_alloc_skcipher(cms, 0, CRYPTO_ALG_ASYNC); + tfm = crypto_alloc_sync_skcipher(cms, 0, 0); if (IS_ERR(tfm)) return PTR_ERR(tfm); - err = crypto_skcipher_setkey(tfm, info->lo_encrypt_key, - info->lo_encrypt_key_size); - + err = crypto_sync_skcipher_setkey(tfm, info->lo_encrypt_key, + info->lo_encrypt_key_size); + if (err != 0) goto out_free_tfm; @@ -94,7 +94,7 @@ cryptoloop_init(struct loop_device *lo, const struct loop_info64 *info) return 0; out_free_tfm: - crypto_free_skcipher(tfm); + crypto_free_sync_skcipher(tfm); out: return err; @@ -109,8 +109,8 @@ cryptoloop_transfer(struct loop_device *lo, int cmd, struct page *loop_page, unsigned loop_off, int size, sector_t IV) { - struct crypto_skcipher *tfm = lo->key_data; - SKCIPHER_REQUEST_ON_STACK(req, tfm); + struct crypto_sync_skcipher *tfm = lo->key_data; + SYNC_SKCIPHER_REQUEST_ON_STACK(req, tfm); struct scatterlist sg_out; struct scatterlist sg_in; @@ -119,7 +119,7 @@ cryptoloop_transfer(struct loop_device *lo, int cmd, unsigned in_offs, out_offs; int err; - skcipher_request_set_tfm(req, tfm); + skcipher_request_set_sync_tfm(req, tfm); skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL); @@ -175,9 +175,9 @@ cryptoloop_ioctl(struct loop_device *lo, int cmd, unsigned long arg) static int cryptoloop_release(struct loop_device *lo) { - struct crypto_skcipher *tfm = lo->key_data; + struct crypto_sync_skcipher *tfm = lo->key_data; if (tfm != NULL) { - crypto_free_skcipher(tfm); + crypto_free_sync_skcipher(tfm); lo->key_data = NULL; return 0; }