diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2021-01-02 14:59:09 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-01-12 20:10:20 +0100 |
| commit | 457b67797cba7bb20e7754b622b1246ad1d521fd (patch) | |
| tree | 83ab03b6b9e7e5c8d34a876244dd6eab4eea0208 /crypto | |
| parent | 9540ea23f62391050da23c2dd47e76bdfb5dcbd5 (diff) | |
crypto: ecdh - avoid buffer overflow in ecdh_set_secret()
commit 0aa171e9b267ce7c52d3a3df7bc9c1fc0203dec5 upstream.
Pavel reports that commit 17858b140bf4 ("crypto: ecdh - avoid unaligned
accesses in ecdh_set_secret()") fixes one problem but introduces another:
the unconditional memcpy() introduced by that commit may overflow the
target buffer if the source data is invalid, which could be the result of
intentional tampering.
So check params.key_size explicitly against the size of the target buffer
before validating the key further.
Fixes: 17858b140bf4 ("crypto: ecdh - avoid unaligned accesses in ecdh_set_secret()")
Reported-by: Pavel Machek <pavel@denx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/ecdh.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/crypto/ecdh.c b/crypto/ecdh.c index a6e1a5d43fa7..34605509b41a 100644 --- a/crypto/ecdh.c +++ b/crypto/ecdh.c @@ -43,7 +43,8 @@ static int ecdh_set_secret(struct crypto_kpp *tfm, const void *buf, struct ecdh params; unsigned int ndigits; - if (crypto_ecdh_decode_key(buf, len, ¶ms) < 0) + if (crypto_ecdh_decode_key(buf, len, ¶ms) < 0 || + params.key_size > sizeof(ctx->private_key)) return -EINVAL; ndigits = ecdh_supported_curve(params.curve_id); |