From d5c3b17898993c3461fb3f0497f45098ffd72ac6 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 30 Mar 2018 09:55:44 -0700 Subject: crypto: ecc - Actually remove stack VLA usage On the quest to remove all VLAs from the kernel[1], this avoids VLAs by just using the maximum allocation size (4 bytes) for stack arrays. All the VLAs in ecc were either 3 or 4 bytes (or a multiple), so just make it 4 bytes all the time. Initialization routines are adjusted to check that ndigits does not end up larger than the arrays. This includes a removal of the earlier attempt at this fix from commit a963834b4742 ("crypto/ecc: Remove stack VLA usage") [1] https://lkml.org/lkml/2018/3/7/621 Signed-off-by: Kees Cook Signed-off-by: Herbert Xu --- crypto/ecdh.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'crypto/ecdh.c') diff --git a/crypto/ecdh.c b/crypto/ecdh.c index d2ec33f0e098..bf6300175b9c 100644 --- a/crypto/ecdh.c +++ b/crypto/ecdh.c @@ -30,8 +30,8 @@ static inline struct ecdh_ctx *ecdh_get_ctx(struct crypto_kpp *tfm) static unsigned int ecdh_supported_curve(unsigned int curve_id) { switch (curve_id) { - case ECC_CURVE_NIST_P192: return 3; - case ECC_CURVE_NIST_P256: return 4; + case ECC_CURVE_NIST_P192: return ECC_CURVE_NIST_P192_DIGITS; + case ECC_CURVE_NIST_P256: return ECC_CURVE_NIST_P256_DIGITS; default: return 0; } } -- cgit v1.2.3-55-g7522