Herbert, On Fri, Feb 01, 2019 at 02:26:55PM +0800, Herbert Xu wrote: > On Fri, Jan 25, 2019 at 09:01:16PM +0300, Vitaly Chikunov wrote: > > > > @@ -781,36 +780,17 @@ static int tpm_key_verify_signature(const struct key *key, > > if (!req) > > goto error_free_tfm; > > > > - ret = -ENOMEM; > > - outlen = crypto_akcipher_maxsize(tfm); > > - output = kmalloc(outlen, GFP_KERNEL); > > - if (!output) > > - goto error_free_req; > > - > > - sg_init_one(&sig_sg, sig->s, sig->s_size); > > - sg_init_one(&digest_sg, output, outlen); > > - akcipher_request_set_crypt(req, &sig_sg, &digest_sg, sig->s_size, > > - outlen); > > + sg_init_table(&src_sg, 2); > > + sg_set_buf(&src_sg[0], sig->s, sig->s_size); > > + sg_set_buf(&src_sg[1], sig->digest, sig->digest_size); > > + akcipher_request_set_crypt(req, &src_sg, NULL, sig->s_size, > > + sig->digest_size); > > It's not clear that sig->digest is guaranteed to be kmalloc memory. > In any case, it's best not to mix unrelated changes in a single > patch. So please keep the kmalloc on output and then copy > sig->digest into it and put output into the SG list. It is not guaranteed that sig->s will be kmalloc memory either. (Except we know it for sure like we know the same about sig->digest). You can see in public_key_signature_free() that both fields are kfree'd together. So, I don't understand why we should treat sig->digest differently than sig->s. I was just removing kmalloc'ed output as crypto_akcipher_verify() does not need any output anymore. So, it's not some sort of mixing unrelated changes, from my point of view. Thanks, > > Thanks, > -- > Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> > Home Page: http://gondor.apana.org.au/~herbert/ > PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
