From patchwork Wed May 12 14:46:07 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 437964 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9DAC4C43617 for ; Wed, 12 May 2021 16:45:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6429561221 for ; Wed, 12 May 2021 16:45:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244388AbhELQpt (ORCPT ); Wed, 12 May 2021 12:45:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:57420 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238398AbhELQiy (ORCPT ); Wed, 12 May 2021 12:38:54 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id B23AB61CD3; Wed, 12 May 2021 16:03:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620835381; bh=ipny/XQ34DvAw3xp5zETAC8Ek0RH55ndwdTEUk5mhPw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iNpqHVKVUXlzdQcIPJ1QhnNwQk2bNjq1swDxNOwHrpmyV262O0Xr4pJBytRPVqgX8 mp568Au/vns0ZmRhnXBTHbYeOHpPqebSD74B6LNYiykXhb4kL2vo1SkYqhQlf2HnTE nZwAlQKVC7egcmjfQfPGu6LNLGtc1nQwC0conIzg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ard Biesheuvel , Herbert Xu , Sasha Levin Subject: [PATCH 5.12 321/677] crypto: arm64/aes-ce - deal with oversight in new CTR carry code Date: Wed, 12 May 2021 16:46:07 +0200 Message-Id: <20210512144847.896548602@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144837.204217980@linuxfoundation.org> References: <20210512144837.204217980@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Ard Biesheuvel [ Upstream commit 0f19dbc994dcb7f7137f2e056e813c84530b7538 ] The new carry handling code in the CTR driver can deal with a carry occurring in the 4x/5x parallel code path, by using a computed goto to jump into the carry sequence at the right place as to only apply the carry to a subset of the blocks being processed. If the lower half of the counter wraps and ends up at exactly 0x0, a carry needs to be applied to the counter, but not to the counter values taken for the 4x/5x parallel sequence. In this case, the computed goto skips all register assignments, and branches straight to the jump instruction that gets us back to the fast path. This produces the correct result, but due to the fact that this branch target does not carry the correct BTI annotation, this fails when BTI is enabled. Let's omit the computed goto entirely in this case, and jump straight back to the fast path after applying the carry to the main counter. Fixes: 5318d3db465d ("crypto: arm64/aes-ctr - improve tail handling") Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin --- arch/arm64/crypto/aes-modes.S | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/crypto/aes-modes.S b/arch/arm64/crypto/aes-modes.S index bbdb54702aa7..247011356d11 100644 --- a/arch/arm64/crypto/aes-modes.S +++ b/arch/arm64/crypto/aes-modes.S @@ -359,6 +359,7 @@ ST5( mov v4.16b, vctr.16b ) ins vctr.d[0], x8 /* apply carry to N counter blocks for N := x12 */ + cbz x12, 2f adr x16, 1f sub x16, x16, x12, lsl #3 br x16