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 ACA0BEEB560 for ; Fri, 8 Sep 2023 18:19:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344104AbjIHST4 (ORCPT ); Fri, 8 Sep 2023 14:19:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41686 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344121AbjIHSTL (ORCPT ); Fri, 8 Sep 2023 14:19:11 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D82A5211F; Fri, 8 Sep 2023 11:18:29 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 11E0EC4339A; Fri, 8 Sep 2023 18:16:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1694197002; bh=YvR4knq0LQJhkdyDueZsyjbvvnvnk0YhCZr0x5mFc5U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=s8DHz5b652S+GhhxSx+W2EQ5MoHt/vFbIBUuzSEmvO2D71Jg4nxZKn/dmkOzwP6+r bgemlxYmzU0umBQrA5Zc7ihZPXM8OcF0grWdBkre6MWqRPbkX3qEIUpxMDKiEJEj9T Gir5W2NauHAGTKtU5pL9yRaYBMurxmqFEAKK3Gxc+iiVteOlqWi7IH3GH4TI1HI8dR qkxf4Z4H+ZPL9UagBG+8jEV5IJd4zsLOR8PzgT2b8LVM+5q+olTdRQx4qGn8mBcIFc uUxPL4fo6/ng3zIkf+IL26vZZ+q6XV0zWSMuobZrpBeGUhaFecvKG50emyR6LbUIUf qoj0SNZhe/M2Q== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Mark O'Donovan , Herbert Xu , Sasha Levin , zohar@linux.ibm.com Subject: [PATCH AUTOSEL 6.4 17/41] crypto: lib/mpi - avoid null pointer deref in mpi_cmp_ui() Date: Fri, 8 Sep 2023 14:15:31 -0400 Message-Id: <20230908181555.3459640-17-sashal@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230908181555.3459640-1-sashal@kernel.org> References: <20230908181555.3459640-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.4.15 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mark O'Donovan [ Upstream commit 9e47a758b70167c9301d2b44d2569f86c7796f2d ] During NVMeTCP Authentication a controller can trigger a kernel oops by specifying the 8192 bit Diffie Hellman group and passing a correctly sized, but zeroed Diffie Hellamn value. mpi_cmp_ui() was detecting this if the second parameter was 0, but 1 is passed from dh_is_pubkey_valid(). This causes the null pointer u->d to be dereferenced towards the end of mpi_cmp_ui() Signed-off-by: Mark O'Donovan Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin --- lib/mpi/mpi-cmp.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/lib/mpi/mpi-cmp.c b/lib/mpi/mpi-cmp.c index c4cfa3ff05818..0835b6213235e 100644 --- a/lib/mpi/mpi-cmp.c +++ b/lib/mpi/mpi-cmp.c @@ -25,8 +25,12 @@ int mpi_cmp_ui(MPI u, unsigned long v) mpi_limb_t limb = v; mpi_normalize(u); - if (!u->nlimbs && !limb) - return 0; + if (u->nlimbs == 0) { + if (v == 0) + return 0; + else + return -1; + } if (u->sign) return -1; if (u->nlimbs > 1) -- 2.40.1