From 149c4e6ef7788d58b9c05eed9fb85e0f5a2c3456 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 18 Jun 2019 11:21:53 +0200 Subject: [PATCH] crypto: testmgr - dynamically allocate crypto_shash The largest stack object in this file is now the shash descriptor. Since there are many other stack variables, this can push it over the 1024 byte warning limit, in particular with clang and KASAN: crypto/testmgr.c:1693:12: error: stack frame size of 1312 bytes in function '__alg_test_hash' [-Werror,-Wframe-larger-than=] Make test_hash_vs_generic_impl() do the same thing as the corresponding eaed and skcipher functions by allocating the descriptor dynamically. We can still do better than this, but it brings us well below the 1024 byte limit. Suggested-by: Eric Biggers Fixes: 9a8a6b3f0950 ("crypto: testmgr - fuzz hashes against their generic implementation") Signed-off-by: Arnd Bergmann Reviewed-by: Eric Biggers Signed-off-by: Herbert Xu --- crypto/testmgr.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/crypto/testmgr.c b/crypto/testmgr.c index ace4c260ea5d..d760f5cd35b2 100644 --- a/crypto/testmgr.c +++ b/crypto/testmgr.c @@ -1508,14 +1508,12 @@ static int test_hash_vec(const char *driver, const struct hash_testvec *vec, * Generate a hash test vector from the given implementation. * Assumes the buffers in 'vec' were already allocated. */ -static void generate_random_hash_testvec(struct crypto_shash *tfm, +static void generate_random_hash_testvec(struct shash_desc *desc, struct hash_testvec *vec, unsigned int maxkeysize, unsigned int maxdatasize, char *name, size_t max_namelen) { - SHASH_DESC_ON_STACK(desc, tfm); - /* Data */ vec->psize = generate_random_length(maxdatasize); generate_random_bytes((u8 *)vec->plaintext, vec->psize); @@ -1532,7 +1530,7 @@ static void generate_random_hash_testvec(struct crypto_shash *tfm, vec->ksize = 1 + (prandom_u32() % maxkeysize); generate_random_bytes((u8 *)vec->key, vec->ksize); - vec->setkey_error = crypto_shash_setkey(tfm, vec->key, + vec->setkey_error = crypto_shash_setkey(desc->tfm, vec->key, vec->ksize); /* If the key couldn't be set, no need to continue to digest. */ if (vec->setkey_error) @@ -1540,7 +1538,6 @@ static void generate_random_hash_testvec(struct crypto_shash *tfm, } /* Digest */ - desc->tfm = tfm; vec->digest_error = crypto_shash_digest(desc, vec->plaintext, vec->psize, (u8 *)vec->digest); done: @@ -1567,6 +1564,7 @@ static int test_hash_vs_generic_impl(const char *driver, const char *algname = crypto_hash_alg_common(tfm)->base.cra_name; char _generic_driver[CRYPTO_MAX_ALG_NAME]; struct crypto_shash *generic_tfm = NULL; + struct shash_desc *generic_desc = NULL; unsigned int i; struct hash_testvec vec = { 0 }; char vec_name[64]; @@ -1606,6 +1604,14 @@ static int test_hash_vs_generic_impl(const char *driver, goto out; } + generic_desc = kzalloc(sizeof(*desc) + + crypto_shash_descsize(generic_tfm), GFP_KERNEL); + if (!generic_desc) { + err = -ENOMEM; + goto out; + } + generic_desc->tfm = generic_tfm; + /* Check the algorithm properties for consistency. */ if (digestsize != crypto_shash_digestsize(generic_tfm)) { @@ -1637,7 +1643,7 @@ static int test_hash_vs_generic_impl(const char *driver, } for (i = 0; i < fuzz_iterations * 8; i++) { - generate_random_hash_testvec(generic_tfm, &vec, + generate_random_hash_testvec(generic_desc, &vec, maxkeysize, maxdatasize, vec_name, sizeof(vec_name)); generate_random_testvec_config(cfg, cfgname, sizeof(cfgname)); @@ -1655,6 +1661,7 @@ out: kfree(vec.plaintext); kfree(vec.digest); crypto_free_shash(generic_tfm); + kzfree(generic_desc); return err; } #else /* !CONFIG_CRYPTO_MANAGER_EXTRA_TESTS */ -- 2.30.2