From: "Larry H." Subject: [patch 5/5] Apply the PG_sensitive flag to the CryptoAPI subsystem Date: Wed, 20 May 2009 12:05:19 -0700 Message-ID: <20090520190519.GE10756@oblivion.subreption.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linus Torvalds , linux-mm@kvack.org, Ingo Molnar , pageexec@freemail.hu, linux-crypto@vger.kernel.org To: linux-kernel@vger.kernel.org Return-path: Content-Disposition: inline Sender: owner-linux-mm@kvack.org List-Id: linux-crypto.vger.kernel.org This patch deploys the use of the PG_sensitive page allocator flag within the CryptoAPI subsystem, in all relevant locations where algorithm and key contexts are allocated. Some calls to memset for zeroing the buffers have been removed to avoid duplication of the sanitizing process, since this is already taken care of by the allocator during page freeing. The only noticeable impact on performance might be in the blkcipher modifications, although this is likely negligible and balanced with the security benefits of this patch in the long term. Signed-off-by: Larry H. --- crypto/ablkcipher.c | 3 +-- crypto/aead.c | 5 ++--- crypto/ahash.c | 3 +-- crypto/algapi.c | 2 +- crypto/api.c | 7 +++---- crypto/authenc.c | 2 +- crypto/blkcipher.c | 11 +++++------ crypto/cipher.c | 3 +-- crypto/cryptd.c | 2 +- crypto/gcm.c | 6 +++--- crypto/hash.c | 3 +-- crypto/rng.c | 2 +- crypto/seqiv.c | 5 +++-- crypto/shash.c | 3 +-- 14 files changed, 25 insertions(+), 32 deletions(-) Index: linux-2.6/crypto/ablkcipher.c =================================================================== --- linux-2.6.orig/crypto/ablkcipher.c +++ linux-2.6/crypto/ablkcipher.c @@ -35,14 +35,13 @@ static int setkey_unaligned(struct crypt unsigned long absize; absize = keylen + alignmask; - buffer = kmalloc(absize, GFP_ATOMIC); + buffer = kmalloc(absize, GFP_ATOMIC | GFP_SENSITIVE); if (!buffer) return -ENOMEM; alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); memcpy(alignbuffer, key, keylen); ret = cipher->setkey(tfm, alignbuffer, keylen); - memset(alignbuffer, 0, keylen); kfree(buffer); return ret; } Index: linux-2.6/crypto/aead.c =================================================================== --- linux-2.6.orig/crypto/aead.c +++ linux-2.6/crypto/aead.c @@ -33,14 +33,13 @@ static int setkey_unaligned(struct crypt unsigned long absize; absize = keylen + alignmask; - buffer = kmalloc(absize, GFP_ATOMIC); + buffer = kmalloc(absize, GFP_ATOMIC | GFP_SENSITIVE); if (!buffer) return -ENOMEM; alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); memcpy(alignbuffer, key, keylen); ret = aead->setkey(tfm, alignbuffer, keylen); - memset(alignbuffer, 0, keylen); kfree(buffer); return ret; } @@ -232,7 +231,7 @@ struct crypto_instance *aead_geniv_alloc if (IS_ERR(name)) return ERR_PTR(err); - inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL | GFP_SENSITIVE); if (!inst) return ERR_PTR(-ENOMEM); Index: linux-2.6/crypto/ahash.c =================================================================== --- linux-2.6.orig/crypto/ahash.c +++ linux-2.6/crypto/ahash.c @@ -138,14 +138,13 @@ static int ahash_setkey_unaligned(struct unsigned long absize; absize = keylen + alignmask; - buffer = kmalloc(absize, GFP_ATOMIC); + buffer = kmalloc(absize, GFP_ATOMIC | GFP_SENSITIVE); if (!buffer) return -ENOMEM; alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); memcpy(alignbuffer, key, keylen); ret = ahash->setkey(tfm, alignbuffer, keylen); - memset(alignbuffer, 0, keylen); kfree(buffer); return ret; } Index: linux-2.6/crypto/algapi.c =================================================================== --- linux-2.6.orig/crypto/algapi.c +++ linux-2.6/crypto/algapi.c @@ -634,7 +634,7 @@ struct crypto_instance *crypto_alloc_ins struct crypto_spawn *spawn; int err; - inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL | GFP_SENSITIVE); if (!inst) return ERR_PTR(-ENOMEM); Index: linux-2.6/crypto/api.c =================================================================== --- linux-2.6.orig/crypto/api.c +++ linux-2.6/crypto/api.c @@ -114,7 +114,7 @@ struct crypto_larval *crypto_larval_allo { struct crypto_larval *larval; - larval = kzalloc(sizeof(*larval), GFP_KERNEL); + larval = kzalloc(sizeof(*larval), GFP_KERNEL | GFP_SENSITIVE); if (!larval) return ERR_PTR(-ENOMEM); @@ -380,7 +380,7 @@ struct crypto_tfm *__crypto_alloc_tfm(st int err = -ENOMEM; tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask); - tfm = kzalloc(tfm_size, GFP_KERNEL); + tfm = kzalloc(tfm_size, GFP_KERNEL | GFP_SENSITIVE); if (tfm == NULL) goto out_err; @@ -476,7 +476,7 @@ struct crypto_tfm *crypto_create_tfm(str tfmsize = frontend->tfmsize; total = tfmsize + sizeof(*tfm) + frontend->extsize(alg, frontend); - mem = kzalloc(total, GFP_KERNEL); + mem = kzalloc(total, GFP_KERNEL | GFP_SENSITIVE); if (mem == NULL) goto out_err; @@ -592,7 +592,6 @@ void crypto_destroy_tfm(void *mem, struc alg->cra_exit(tfm); crypto_exit_ops(tfm); crypto_mod_put(alg); - memset(mem, 0, size); kfree(mem); } EXPORT_SYMBOL_GPL(crypto_destroy_tfm); Index: linux-2.6/crypto/authenc.c =================================================================== --- linux-2.6.orig/crypto/authenc.c +++ linux-2.6/crypto/authenc.c @@ -397,7 +397,7 @@ static struct crypto_instance *crypto_au if (IS_ERR(enc_name)) goto out_put_auth; - inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL | GFP_SENSITIVE); err = -ENOMEM; if (!inst) goto out_put_auth; Index: linux-2.6/crypto/blkcipher.c =================================================================== --- linux-2.6.orig/crypto/blkcipher.c +++ linux-2.6/crypto/blkcipher.c @@ -161,7 +161,7 @@ static inline int blkcipher_next_slow(st n = aligned_bsize * 3 - (alignmask + 1) + (alignmask & ~(crypto_tfm_ctx_alignment() - 1)); - walk->buffer = kmalloc(n, GFP_ATOMIC); + walk->buffer = kmalloc(n, GFP_ATOMIC | GFP_SENSITIVE); if (!walk->buffer) return blkcipher_walk_done(desc, walk, -ENOMEM); @@ -242,7 +242,7 @@ static int blkcipher_walk_next(struct bl !scatterwalk_aligned(&walk->out, alignmask)) { walk->flags |= BLKCIPHER_WALK_COPY; if (!walk->page) { - walk->page = (void *)__get_free_page(GFP_ATOMIC); + walk->page = (void *)__get_free_page(GFP_ATOMIC|GFP_SENSITIVE); if (!walk->page) n = 0; } @@ -287,7 +287,7 @@ static inline int blkcipher_copy_iv(stru u8 *iv; size += alignmask & ~(crypto_tfm_ctx_alignment() - 1); - walk->buffer = kmalloc(size, GFP_ATOMIC); + walk->buffer = kmalloc(size, GFP_ATOMIC | GFP_SENSITIVE); if (!walk->buffer) return -ENOMEM; @@ -366,14 +366,13 @@ static int setkey_unaligned(struct crypt unsigned long absize; absize = keylen + alignmask; - buffer = kmalloc(absize, GFP_ATOMIC); + buffer = kmalloc(absize, GFP_ATOMIC | GFP_SENSITIVE); if (!buffer) return -ENOMEM; alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); memcpy(alignbuffer, key, keylen); ret = cipher->setkey(tfm, alignbuffer, keylen); - memset(alignbuffer, 0, keylen); kfree(buffer); return ret; } @@ -569,7 +568,7 @@ struct crypto_instance *skcipher_geniv_a if (IS_ERR(name)) return ERR_PTR(err); - inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL | GFP_SENSITIVE); if (!inst) return ERR_PTR(-ENOMEM); Index: linux-2.6/crypto/cipher.c =================================================================== --- linux-2.6.orig/crypto/cipher.c +++ linux-2.6/crypto/cipher.c @@ -30,14 +30,13 @@ static int setkey_unaligned(struct crypt unsigned long absize; absize = keylen + alignmask; - buffer = kmalloc(absize, GFP_ATOMIC); + buffer = kmalloc(absize, GFP_ATOMIC | GFP_SENSITIVE); if (!buffer) return -ENOMEM; alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); memcpy(alignbuffer, key, keylen); ret = cia->cia_setkey(tfm, alignbuffer, keylen); - memset(alignbuffer, 0, keylen); kfree(buffer); return ret; Index: linux-2.6/crypto/cryptd.c =================================================================== --- linux-2.6.orig/crypto/cryptd.c +++ linux-2.6/crypto/cryptd.c @@ -196,7 +196,7 @@ static struct crypto_instance *cryptd_al struct cryptd_instance_ctx *ctx; int err; - inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL | GFP_SENSITIVE); if (!inst) { inst = ERR_PTR(-ENOMEM); goto out; Index: linux-2.6/crypto/gcm.c =================================================================== --- linux-2.6.orig/crypto/gcm.c +++ linux-2.6/crypto/gcm.c @@ -208,7 +208,7 @@ static int crypto_gcm_setkey(struct cryp CRYPTO_TFM_RES_MASK); data = kzalloc(sizeof(*data) + crypto_ablkcipher_reqsize(ctr), - GFP_KERNEL); + GFP_KERNEL | GFP_SENSITIVE); if (!data) return -ENOMEM; @@ -454,7 +454,7 @@ static struct crypto_instance *crypto_gc if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) return ERR_PTR(-EINVAL); - inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL | GFP_SENSITIVE); if (!inst) return ERR_PTR(-ENOMEM); @@ -703,7 +703,7 @@ static struct crypto_instance *crypto_rf if (IS_ERR(ccm_name)) return ERR_PTR(err); - inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL | GFP_SENSITIVE); if (!inst) return ERR_PTR(-ENOMEM); Index: linux-2.6/crypto/hash.c =================================================================== --- linux-2.6.orig/crypto/hash.c +++ linux-2.6/crypto/hash.c @@ -35,14 +35,13 @@ static int hash_setkey_unaligned(struct unsigned long absize; absize = keylen + alignmask; - buffer = kmalloc(absize, GFP_ATOMIC); + buffer = kmalloc(absize, GFP_ATOMIC | GFP_SENSITIVE); if (!buffer) return -ENOMEM; alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); memcpy(alignbuffer, key, keylen); ret = alg->setkey(crt, alignbuffer, keylen); - memset(alignbuffer, 0, keylen); kfree(buffer); return ret; } Index: linux-2.6/crypto/rng.c =================================================================== --- linux-2.6.orig/crypto/rng.c +++ linux-2.6/crypto/rng.c @@ -32,7 +32,7 @@ static int rngapi_reset(struct crypto_rn int err; if (!seed && slen) { - buf = kmalloc(slen, GFP_KERNEL); + buf = kmalloc(slen, GFP_KERNEL | GFP_SENSITIVE); if (!buf) return -ENOMEM; Index: linux-2.6/crypto/seqiv.c =================================================================== --- linux-2.6.orig/crypto/seqiv.c +++ linux-2.6/crypto/seqiv.c @@ -115,9 +115,10 @@ static int seqiv_givencrypt(struct skcip if (unlikely(!IS_ALIGNED((unsigned long)info, crypto_ablkcipher_alignmask(geniv) + 1))) { - info = kmalloc(ivsize, req->creq.base.flags & + info = kmalloc(ivsize, (req->creq.base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL: - GFP_ATOMIC); + GFP_ATOMIC) + | GFP_SENSITIVE); if (!info) return -ENOMEM; Index: linux-2.6/crypto/shash.c =================================================================== --- linux-2.6.orig/crypto/shash.c +++ linux-2.6/crypto/shash.c @@ -37,14 +37,13 @@ static int shash_setkey_unaligned(struct int err; absize = keylen + (alignmask & ~(CRYPTO_MINALIGN - 1)); - buffer = kmalloc(absize, GFP_KERNEL); + buffer = kmalloc(absize, GFP_KERNEL | GFP_SENSITIVE); if (!buffer) return -ENOMEM; alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); memcpy(alignbuffer, key, keylen); err = shash->setkey(tfm, alignbuffer, keylen); - memset(alignbuffer, 0, keylen); kfree(buffer); return err; } -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org