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| author | Kees Cook <keescook@chromium.org> | 2018-08-07 14:18:38 -0700 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2018-09-04 11:35:03 +0800 |
| commit | b68a7ec1e9a3efac53ae26a1658a553825a2375c (patch) | |
| tree | 6ad87c86f0fc4aeafee091c6d43043876f081d0b /crypto/shash.c | |
| parent | ebf533adc877d9171800bbce77372d8051fc35c2 (diff) | |
| download | linux-b68a7ec1e9a3efac53ae26a1658a553825a2375c.tar.gz linux-b68a7ec1e9a3efac53ae26a1658a553825a2375c.tar.bz2 linux-b68a7ec1e9a3efac53ae26a1658a553825a2375c.zip | |
crypto: hash - Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this
removes the VLAs in SHASH_DESC_ON_STACK (via crypto_shash_descsize())
by using the maximum allowable size (which is now more clearly captured
in a macro), along with a few other cases. Similar limits are turned into
macros as well.
A review of existing sizes shows that SHA512_DIGEST_SIZE (64) is the
largest digest size and that sizeof(struct sha3_state) (360) is the
largest descriptor size. The corresponding maximums are reduced.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/shash.c')
| -rw-r--r-- | crypto/shash.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/crypto/shash.c b/crypto/shash.c index 5d732c6bb4b2..86d76b5c626c 100644 --- a/crypto/shash.c +++ b/crypto/shash.c @@ -458,9 +458,9 @@ static int shash_prepare_alg(struct shash_alg *alg) { struct crypto_alg *base = &alg->base; - if (alg->digestsize > PAGE_SIZE / 8 || - alg->descsize > PAGE_SIZE / 8 || - alg->statesize > PAGE_SIZE / 8) + if (alg->digestsize > HASH_MAX_DIGESTSIZE || + alg->descsize > HASH_MAX_DESCSIZE || + alg->statesize > HASH_MAX_STATESIZE) return -EINVAL; base->cra_type = &crypto_shash_type; |