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 667EBEEB560 for ; Fri, 8 Sep 2023 18:17:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343863AbjIHSRn (ORCPT ); Fri, 8 Sep 2023 14:17:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47226 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232934AbjIHSR3 (ORCPT ); Fri, 8 Sep 2023 14:17:29 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 54D6F268D; Fri, 8 Sep 2023 11:17:06 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D2034C116AB; Fri, 8 Sep 2023 18:14:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1694196870; bh=YvR4knq0LQJhkdyDueZsyjbvvnvnk0YhCZr0x5mFc5U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=E7vLSd8O8kS+QtrrQLovbsXL8IP4D4ixsvfYn+pJ1yCdacbJDk337kX5yvO6IDNDb S8uC4bNzmUmOdlp7D5PiNKgKC9cKZ9K3lKDVqsUepB7Pf8quuYUjOZvgDfxyQavB/A UJ9DoYHXnEszE0WK6UiLjpBSA/ILZVw+SJRHad/A5ncUR65SqMnhPdm5441F+BaOAd gBCpaQ+hoInS/85tEjtj75UMvPBznOG1udCBr71w3X8SnmRQ/BQ1vkhCHgoM28R1DZ s+Oi/ihJ31SzI7vLgLws2BIPaU8IcjYua1dq0sknJ/1CKbSwTJEcmSgTJ+XyEWzv59 NssT1pVFoR60A== 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 6.5 20/45] crypto: lib/mpi - avoid null pointer deref in mpi_cmp_ui() Date: Fri, 8 Sep 2023 14:13:01 -0400 Message-Id: <20230908181327.3459042-20-sashal@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230908181327.3459042-1-sashal@kernel.org> References: <20230908181327.3459042-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.5.2 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