From 8d605398425843c7ce3c0e9a0434d832d3bd54cc Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 18 Sep 2018 19:10:51 -0700 Subject: [PATCH] crypto: null - 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 Signed-off-by: Kees Cook Signed-off-by: Herbert Xu --- crypto/algif_aead.c | 12 ++++++------ crypto/authenc.c | 8 ++++---- crypto/authencesn.c | 8 ++++---- crypto/crypto_null.c | 11 +++++------ crypto/echainiv.c | 4 ++-- crypto/gcm.c | 8 ++++---- crypto/seqiv.c | 4 ++-- include/crypto/internal/geniv.h | 2 +- include/crypto/null.h | 2 +- 9 files changed, 29 insertions(+), 30 deletions(-) diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c index c40a8c7ee8ae..eb100a04ce9f 100644 --- a/crypto/algif_aead.c +++ b/crypto/algif_aead.c @@ -42,7 +42,7 @@ struct aead_tfm { struct crypto_aead *aead; - struct crypto_skcipher *null_tfm; + struct crypto_sync_skcipher *null_tfm; }; static inline bool aead_sufficient_data(struct sock *sk) @@ -75,13 +75,13 @@ static int aead_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) return af_alg_sendmsg(sock, msg, size, ivsize); } -static int crypto_aead_copy_sgl(struct crypto_skcipher *null_tfm, +static int crypto_aead_copy_sgl(struct crypto_sync_skcipher *null_tfm, struct scatterlist *src, struct scatterlist *dst, unsigned int len) { - SKCIPHER_REQUEST_ON_STACK(skreq, null_tfm); + SYNC_SKCIPHER_REQUEST_ON_STACK(skreq, null_tfm); - skcipher_request_set_tfm(skreq, null_tfm); + skcipher_request_set_sync_tfm(skreq, null_tfm); skcipher_request_set_callback(skreq, CRYPTO_TFM_REQ_MAY_BACKLOG, NULL, NULL); skcipher_request_set_crypt(skreq, src, dst, len, NULL); @@ -99,7 +99,7 @@ static int _aead_recvmsg(struct socket *sock, struct msghdr *msg, struct af_alg_ctx *ctx = ask->private; struct aead_tfm *aeadc = pask->private; struct crypto_aead *tfm = aeadc->aead; - struct crypto_skcipher *null_tfm = aeadc->null_tfm; + struct crypto_sync_skcipher *null_tfm = aeadc->null_tfm; unsigned int i, as = crypto_aead_authsize(tfm); struct af_alg_async_req *areq; struct af_alg_tsgl *tsgl, *tmp; @@ -478,7 +478,7 @@ static void *aead_bind(const char *name, u32 type, u32 mask) { struct aead_tfm *tfm; struct crypto_aead *aead; - struct crypto_skcipher *null_tfm; + struct crypto_sync_skcipher *null_tfm; tfm = kzalloc(sizeof(*tfm), GFP_KERNEL); if (!tfm) diff --git a/crypto/authenc.c b/crypto/authenc.c index 4fa8d40d947b..37f54d1b2f66 100644 --- a/crypto/authenc.c +++ b/crypto/authenc.c @@ -33,7 +33,7 @@ struct authenc_instance_ctx { struct crypto_authenc_ctx { struct crypto_ahash *auth; struct crypto_skcipher *enc; - struct crypto_skcipher *null; + struct crypto_sync_skcipher *null; }; struct authenc_request_ctx { @@ -185,9 +185,9 @@ static int crypto_authenc_copy_assoc(struct aead_request *req) { struct crypto_aead *authenc = crypto_aead_reqtfm(req); struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc); - SKCIPHER_REQUEST_ON_STACK(skreq, ctx->null); + SYNC_SKCIPHER_REQUEST_ON_STACK(skreq, ctx->null); - skcipher_request_set_tfm(skreq, ctx->null); + skcipher_request_set_sync_tfm(skreq, ctx->null); skcipher_request_set_callback(skreq, aead_request_flags(req), NULL, NULL); skcipher_request_set_crypt(skreq, req->src, req->dst, req->assoclen, @@ -318,7 +318,7 @@ static int crypto_authenc_init_tfm(struct crypto_aead *tfm) struct crypto_authenc_ctx *ctx = crypto_aead_ctx(tfm); struct crypto_ahash *auth; struct crypto_skcipher *enc; - struct crypto_skcipher *null; + struct crypto_sync_skcipher *null; int err; auth = crypto_spawn_ahash(&ictx->auth); diff --git a/crypto/authencesn.c b/crypto/authencesn.c index 50b804747e20..80a25cc04aec 100644 --- a/crypto/authencesn.c +++ b/crypto/authencesn.c @@ -36,7 +36,7 @@ struct crypto_authenc_esn_ctx { unsigned int reqoff; struct crypto_ahash *auth; struct crypto_skcipher *enc; - struct crypto_skcipher *null; + struct crypto_sync_skcipher *null; }; struct authenc_esn_request_ctx { @@ -183,9 +183,9 @@ static int crypto_authenc_esn_copy(struct aead_request *req, unsigned int len) { struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req); struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn); - SKCIPHER_REQUEST_ON_STACK(skreq, ctx->null); + SYNC_SKCIPHER_REQUEST_ON_STACK(skreq, ctx->null); - skcipher_request_set_tfm(skreq, ctx->null); + skcipher_request_set_sync_tfm(skreq, ctx->null); skcipher_request_set_callback(skreq, aead_request_flags(req), NULL, NULL); skcipher_request_set_crypt(skreq, req->src, req->dst, len, NULL); @@ -341,7 +341,7 @@ static int crypto_authenc_esn_init_tfm(struct crypto_aead *tfm) struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(tfm); struct crypto_ahash *auth; struct crypto_skcipher *enc; - struct crypto_skcipher *null; + struct crypto_sync_skcipher *null; int err; auth = crypto_spawn_ahash(&ictx->auth); diff --git a/crypto/crypto_null.c b/crypto/crypto_null.c index 0959b268966c..0bae59922a80 100644 --- a/crypto/crypto_null.c +++ b/crypto/crypto_null.c @@ -26,7 +26,7 @@ #include static DEFINE_MUTEX(crypto_default_null_skcipher_lock); -static struct crypto_skcipher *crypto_default_null_skcipher; +static struct crypto_sync_skcipher *crypto_default_null_skcipher; static int crypto_default_null_skcipher_refcnt; static int null_compress(struct crypto_tfm *tfm, const u8 *src, @@ -152,16 +152,15 @@ MODULE_ALIAS_CRYPTO("compress_null"); MODULE_ALIAS_CRYPTO("digest_null"); MODULE_ALIAS_CRYPTO("cipher_null"); -struct crypto_skcipher *crypto_get_default_null_skcipher(void) +struct crypto_sync_skcipher *crypto_get_default_null_skcipher(void) { - struct crypto_skcipher *tfm; + struct crypto_sync_skcipher *tfm; mutex_lock(&crypto_default_null_skcipher_lock); tfm = crypto_default_null_skcipher; if (!tfm) { - tfm = crypto_alloc_skcipher("ecb(cipher_null)", - 0, CRYPTO_ALG_ASYNC); + tfm = crypto_alloc_sync_skcipher("ecb(cipher_null)", 0, 0); if (IS_ERR(tfm)) goto unlock; @@ -181,7 +180,7 @@ void crypto_put_default_null_skcipher(void) { mutex_lock(&crypto_default_null_skcipher_lock); if (!--crypto_default_null_skcipher_refcnt) { - crypto_free_skcipher(crypto_default_null_skcipher); + crypto_free_sync_skcipher(crypto_default_null_skcipher); crypto_default_null_skcipher = NULL; } mutex_unlock(&crypto_default_null_skcipher_lock); diff --git a/crypto/echainiv.c b/crypto/echainiv.c index 45819e6015bf..77e607fdbfb7 100644 --- a/crypto/echainiv.c +++ b/crypto/echainiv.c @@ -47,9 +47,9 @@ static int echainiv_encrypt(struct aead_request *req) info = req->iv; if (req->src != req->dst) { - SKCIPHER_REQUEST_ON_STACK(nreq, ctx->sknull); + SYNC_SKCIPHER_REQUEST_ON_STACK(nreq, ctx->sknull); - skcipher_request_set_tfm(nreq, ctx->sknull); + skcipher_request_set_sync_tfm(nreq, ctx->sknull); skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL); skcipher_request_set_crypt(nreq, req->src, req->dst, diff --git a/crypto/gcm.c b/crypto/gcm.c index 0ad879e1f9b2..e438492db2ca 100644 --- a/crypto/gcm.c +++ b/crypto/gcm.c @@ -50,7 +50,7 @@ struct crypto_rfc4543_instance_ctx { struct crypto_rfc4543_ctx { struct crypto_aead *child; - struct crypto_skcipher *null; + struct crypto_sync_skcipher *null; u8 nonce[4]; }; @@ -1067,9 +1067,9 @@ static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc) unsigned int authsize = crypto_aead_authsize(aead); unsigned int nbytes = req->assoclen + req->cryptlen - (enc ? 0 : authsize); - SKCIPHER_REQUEST_ON_STACK(nreq, ctx->null); + SYNC_SKCIPHER_REQUEST_ON_STACK(nreq, ctx->null); - skcipher_request_set_tfm(nreq, ctx->null); + skcipher_request_set_sync_tfm(nreq, ctx->null); skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL); skcipher_request_set_crypt(nreq, req->src, req->dst, nbytes, NULL); @@ -1093,7 +1093,7 @@ static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm) struct crypto_aead_spawn *spawn = &ictx->aead; struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm); struct crypto_aead *aead; - struct crypto_skcipher *null; + struct crypto_sync_skcipher *null; unsigned long align; int err = 0; diff --git a/crypto/seqiv.c b/crypto/seqiv.c index 39dbf2f7e5f5..64a412be255e 100644 --- a/crypto/seqiv.c +++ b/crypto/seqiv.c @@ -73,9 +73,9 @@ static int seqiv_aead_encrypt(struct aead_request *req) info = req->iv; if (req->src != req->dst) { - SKCIPHER_REQUEST_ON_STACK(nreq, ctx->sknull); + SYNC_SKCIPHER_REQUEST_ON_STACK(nreq, ctx->sknull); - skcipher_request_set_tfm(nreq, ctx->sknull); + skcipher_request_set_sync_tfm(nreq, ctx->sknull); skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL); skcipher_request_set_crypt(nreq, req->src, req->dst, diff --git a/include/crypto/internal/geniv.h b/include/crypto/internal/geniv.h index 2bcfb931bc5b..71be24cd59bd 100644 --- a/include/crypto/internal/geniv.h +++ b/include/crypto/internal/geniv.h @@ -20,7 +20,7 @@ struct aead_geniv_ctx { spinlock_t lock; struct crypto_aead *child; - struct crypto_skcipher *sknull; + struct crypto_sync_skcipher *sknull; u8 salt[] __attribute__ ((aligned(__alignof__(u32)))); }; diff --git a/include/crypto/null.h b/include/crypto/null.h index 15aeef6e30ef..0ef577cc00e3 100644 --- a/include/crypto/null.h +++ b/include/crypto/null.h @@ -9,7 +9,7 @@ #define NULL_DIGEST_SIZE 0 #define NULL_IV_SIZE 0 -struct crypto_skcipher *crypto_get_default_null_skcipher(void); +struct crypto_sync_skcipher *crypto_get_default_null_skcipher(void); void crypto_put_default_null_skcipher(void); #endif