From patchwork Fri Jan 12 00:47:13 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 10160255 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8BB0860327 for ; Fri, 12 Jan 2018 11:29:24 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7A11528985 for ; Fri, 12 Jan 2018 11:29:24 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6DFEC28987; Fri, 12 Jan 2018 11:29:24 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id 3A35728985 for ; Fri, 12 Jan 2018 11:29:23 +0000 (UTC) Received: (qmail 16053 invoked by uid 550); 12 Jan 2018 11:28:38 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Delivered-To: moderator for kernel-hardening@lists.openwall.com Received: (qmail 23911 invoked from network); 12 Jan 2018 00:55:39 -0000 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.46,346,1511856000"; d="scan'208";a="23373831" From: Dan Williams To: linux-kernel@vger.kernel.org Cc: linux-arch@vger.kernel.org, akpm@linux-foundation.org, kernel-hardening@lists.openwall.com, Hideaki YOSHIFUJI , netdev@vger.kernel.org, Alexey Kuznetsov , tglx@linutronix.de, torvalds@linux-foundation.org, "David S. Miller" , Elena Reshetova , alan@linux.intel.com Date: Thu, 11 Jan 2018 16:47:13 -0800 Message-ID: <151571803370.27429.18342496227199960317.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <151571798296.27429.7166552848688034184.stgit@dwillia2-desk3.amr.corp.intel.com> References: <151571798296.27429.7166552848688034184.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.17.1-9-g687f MIME-Version: 1.0 Subject: [kernel-hardening] [PATCH v2 09/19] ipv6: prevent bounds-check bypass via speculative execution X-Virus-Scanned: ClamAV using ClamSMTP Static analysis reports that 'offset' may be a user controlled value that is used as a data dependency reading from a raw6_frag_vec buffer. In order to avoid potential leaks of kernel memory values, block speculative execution of the instruction stream that could issue further reads based on an invalid '*(rfv->c + offset)' value. Based on an original patch by Elena Reshetova. Cc: "David S. Miller" Cc: Alexey Kuznetsov Cc: Hideaki YOSHIFUJI Cc: netdev@vger.kernel.org Signed-off-by: Elena Reshetova Signed-off-by: Dan Williams --- net/ipv6/raw.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index 761a473a07c5..0b7ceeb6f709 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include @@ -725,17 +726,18 @@ static int raw6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb) { struct raw6_frag_vec *rfv = from; + char *rfv_buf; - if (offset < rfv->hlen) { + rfv_buf = array_ptr(rfv->c, offset, rfv->hlen); + if (rfv_buf) { int copy = min(rfv->hlen - offset, len); if (skb->ip_summed == CHECKSUM_PARTIAL) - memcpy(to, rfv->c + offset, copy); + memcpy(to, rfv_buf, copy); else skb->csum = csum_block_add( skb->csum, - csum_partial_copy_nocheck(rfv->c + offset, - to, copy, 0), + csum_partial_copy_nocheck(rfv_buf, to, copy, 0), odd); odd = 0;