crypto: ecc - Fix NULL pointer deref. on no default_rng
authorPierre <pinaraf@pinaraf.info>
Sun, 12 Nov 2017 14:24:32 +0000 (15:24 +0100)
committerHerbert Xu <herbert@gondor.apana.org.au>
Wed, 29 Nov 2017 06:33:24 +0000 (17:33 +1100)
If crypto_get_default_rng returns an error, the
function ecc_gen_privkey should return an error.
Instead, it currently tries to use the default_rng
nevertheless, thus creating a kernel panic with a
NULL pointer dereference.
Returning the error directly, as was supposedly
intended when looking at the code, fixes this.

Signed-off-by: Pierre Ducroquet <pinaraf@pinaraf.info>
Reviewed-by: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto/ecc.c

index 633a9bc..18f32f2 100644 (file)
@@ -964,7 +964,7 @@ int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64 *privkey)
         * DRBG with a security strength of 256.
         */
        if (crypto_get_default_rng())
-               err = -EFAULT;
+               return -EFAULT;
 
        err = crypto_rng_get_bytes(crypto_default_rng, (u8 *)priv, nbytes);
        crypto_put_default_rng();