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 58AE0C7EE25 for ; Wed, 7 Jun 2023 20:52:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235211AbjFGUwC (ORCPT ); Wed, 7 Jun 2023 16:52:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235262AbjFGUvx (ORCPT ); Wed, 7 Jun 2023 16:51:53 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7169611D for ; Wed, 7 Jun 2023 13:51:51 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 4DC586472E for ; Wed, 7 Jun 2023 20:51:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5D625C433D2; Wed, 7 Jun 2023 20:51:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1686171110; bh=yVZUa91cC4AjJsDmOCeAkbo4Wi1nABQ4RHqQaHMya8Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gyhKWKsHHo4Kc3u658INM465owmg/b53iUlZp5/eZu08VLSuOy/Bxhf47Wx2vX55z XasU5pYMOTVynuB+kg81beYxLuKXgKCtdtViZUM2afxKNQ00ZjbVCZjxUSgTOlnl+Z 2dqWqYRr/gdUGISmfFAMEFAXlB+VAH1iC/Yk8qVQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Brijesh Singh , Borislav Petkov , Tom Lendacky , Sean Christopherson , Paolo Bonzini , Ben Hutchings Subject: [PATCH 5.10 114/120] crypto: ccp: Reject SEV commands with mismatching command buffer Date: Wed, 7 Jun 2023 22:17:10 +0200 Message-ID: <20230607200904.520857466@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230607200900.915613242@linuxfoundation.org> References: <20230607200900.915613242@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Sean Christopherson commit d5760dee127bf6f390b05e747369d7c37ae1a7b8 upstream. WARN on and reject SEV commands that provide a valid data pointer, but do not have a known, non-zero length. And conversely, reject commands that take a command buffer but none is provided (data is null). Aside from sanity checking input, disallowing a non-null pointer without a non-zero size will allow a future patch to cleanly handle vmalloc'd data by copying the data to an internal __pa() friendly buffer. Note, this also effectively prevents callers from using commands that have a non-zero length and are not known to the kernel. This is not an explicit goal, but arguably the side effect is a good thing from the kernel's perspective. Cc: Brijesh Singh Cc: Borislav Petkov Cc: Tom Lendacky Signed-off-by: Sean Christopherson Message-Id: <20210406224952.4177376-4-seanjc@google.com> Reviewed-by: Brijesh Singh Acked-by: Tom Lendacky Signed-off-by: Paolo Bonzini Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- drivers/crypto/ccp/sev-dev.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -156,6 +156,7 @@ static int __sev_do_cmd_locked(int cmd, struct sev_device *sev; unsigned int phys_lsb, phys_msb; unsigned int reg, ret = 0; + int buf_len; if (!psp || !psp->sev_data) return -ENODEV; @@ -165,6 +166,10 @@ static int __sev_do_cmd_locked(int cmd, sev = psp->sev_data; + buf_len = sev_cmd_buffer_len(cmd); + if (WARN_ON_ONCE(!data != !buf_len)) + return -EINVAL; + if (data && WARN_ON_ONCE(!virt_addr_valid(data))) return -EINVAL; @@ -176,7 +181,7 @@ static int __sev_do_cmd_locked(int cmd, cmd, phys_msb, phys_lsb, psp_timeout); print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data, - sev_cmd_buffer_len(cmd), false); + buf_len, false); iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); @@ -212,7 +217,7 @@ static int __sev_do_cmd_locked(int cmd, } print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, - sev_cmd_buffer_len(cmd), false); + buf_len, false); return ret; }