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| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2018-08-07 14:18:37 -0700 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2018-09-04 11:35:03 +0800 |
| commit | ebf533adc877d9171800bbce77372d8051fc35c2 (patch) | |
| tree | eae178d2f083b217fd9033081e20c37cb2ffd90c /crypto | |
| parent | d73d67fbcb94409e0a92952750f162d4eb696e96 (diff) | |
| download | lwn-ebf533adc877d9171800bbce77372d8051fc35c2.tar.gz lwn-ebf533adc877d9171800bbce77372d8051fc35c2.zip | |
crypto: ccm - Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this drops
AHASH_REQUEST_ON_STACK by preallocating the ahash request area combined
with the skcipher area (which are not used at the same time).
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/ccm.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/crypto/ccm.c b/crypto/ccm.c index 0a083342ec8c..b242fd0d3262 100644 --- a/crypto/ccm.c +++ b/crypto/ccm.c @@ -50,7 +50,10 @@ struct crypto_ccm_req_priv_ctx { u32 flags; struct scatterlist src[3]; struct scatterlist dst[3]; - struct skcipher_request skreq; + union { + struct ahash_request ahreq; + struct skcipher_request skreq; + }; }; struct cbcmac_tfm_ctx { @@ -181,7 +184,7 @@ static int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain, struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req); struct crypto_aead *aead = crypto_aead_reqtfm(req); struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead); - AHASH_REQUEST_ON_STACK(ahreq, ctx->mac); + struct ahash_request *ahreq = &pctx->ahreq; unsigned int assoclen = req->assoclen; struct scatterlist sg[3]; u8 *odata = pctx->odata; @@ -427,7 +430,7 @@ static int crypto_ccm_init_tfm(struct crypto_aead *tfm) crypto_aead_set_reqsize( tfm, align + sizeof(struct crypto_ccm_req_priv_ctx) + - crypto_skcipher_reqsize(ctr)); + max(crypto_ahash_reqsize(mac), crypto_skcipher_reqsize(ctr))); return 0; |