From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE229C6FA82 for ; Tue, 20 Sep 2022 05:06:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230063AbiITFGZ (ORCPT ); Tue, 20 Sep 2022 01:06:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50514 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230038AbiITFGX (ORCPT ); Tue, 20 Sep 2022 01:06:23 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4835D46D81; Mon, 19 Sep 2022 22:06:22 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id BE216B82453; Tue, 20 Sep 2022 05:06:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id ECDE9C433D7; Tue, 20 Sep 2022 05:06:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1663650379; bh=QrqoAWdyoKqvuCY0mh/a0HFmsrJsaS+3N7uYNdSkTVw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Yj6TGRtyES2UyENyN5roAwj1JkSEk0NFq8/NCDsU83JW02MuftEVkWO1JLu2UN6aK NHCRlRpkQJBWQYW2K6UnyMmvkgmEfSgwpjt/7M8Rx57KEb2Y3bYGQmIayfoEyTokp8 5PGKUFdB0P0fSoNMlSTGtMK8VQq4ei32xTHagXkAGlpA7o7kvDkRAdxQphjJE+nb3n FE4fgYFtC9GWCrArwlzQJPr13SA392QI97T9RbbQI0OW1FxHVYfPg/g823dWuZw5+/ Crbns8zhP/PAKbVA19Tz3NewBT5EQNnZ+hBzRFXONNBxQpVz87GK4FN0NFtIuFo7Fp ybP6de0uVsC2A== Date: Tue, 20 Sep 2022 08:06:15 +0300 From: Jarkko Sakkinen To: Nikolaus Voss Cc: Mimi Zohar , David Howells , James Morris , "Serge E. Hallyn" , linux-integrity@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] KEYS: encrypted: fix key instantiation with user-provided data Message-ID: References: <20220919072317.E41421357@mail.steuer-voss.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220919072317.E41421357@mail.steuer-voss.de> Precedence: bulk List-ID: On Fri, Sep 16, 2022 at 07:45:29AM +0200, Nikolaus Voss wrote: > Commit cd3bc044af48 ("KEYS: encrypted: Instantiate key with user-provided > decrypted data") added key instantiation with user provided decrypted data. > The user data is hex-ascii-encoded but was just memcpy'ed to the binary buffer. > Fix this to use hex2bin instead. > > Fixes: cd3bc044af48 ("KEYS: encrypted: Instantiate key with user-provided decrypted data") > Cc: stable > Signed-off-by: Nikolaus Voss > --- > security/keys/encrypted-keys/encrypted.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c > index e05cfc2e49ae..1e313982af02 100644 > --- a/security/keys/encrypted-keys/encrypted.c > +++ b/security/keys/encrypted-keys/encrypted.c > @@ -627,7 +627,7 @@ static struct encrypted_key_payload *encrypted_key_alloc(struct key *key, > pr_err("encrypted key: instantiation of keys using provided decrypted data is disabled since CONFIG_USER_DECRYPTED_DATA is set to false\n"); > return ERR_PTR(-EINVAL); > } > - if (strlen(decrypted_data) != decrypted_datalen) { > + if (strlen(decrypted_data) != decrypted_datalen * 2) { This looks wrong. What does cap decrypted_data, and why strnlen() is not used? > pr_err("encrypted key: decrypted data provided does not match decrypted data length provided\n"); Using pr_err() is probably wrong here and has different prefix than elsewhere in the file (also most of other uses of pr_err() are wrong apparently). Nothing bad is really happening. And who does make any sense of that error message anyway? For one, I don't understand it. > return ERR_PTR(-EINVAL); > } > @@ -791,8 +791,8 @@ static int encrypted_init(struct encrypted_key_payload *epayload, > ret = encrypted_key_decrypt(epayload, format, hex_encoded_iv); > } else if (decrypted_data) { > get_random_bytes(epayload->iv, ivsize); > - memcpy(epayload->decrypted_data, decrypted_data, > - epayload->decrypted_datalen); > + ret = hex2bin(epayload->decrypted_data, decrypted_data, > + epayload->decrypted_datalen); > } else { > get_random_bytes(epayload->iv, ivsize); > get_random_bytes(epayload->decrypted_data, epayload->decrypted_datalen); > -- > 2.34.1 > BR, Jarkko