From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1511654-1518326464-2-11567460337539121679 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='uk', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1518326464; b=AIA10AD74EO6uk/2jBfor73xwRYOfW899/NX8TGhQP2b9go EYZETIpeWffAI50LdSeYhN0grFia9J9mFyDhkyacxS6+XYE1opTleBG31ECtpW5A XqNPYtuVZ+Ceunky4QA+xhaNYyiU78qmAkUYdcWrlh7KHMN4+xs6Sz6nLWx4xUrk 1WvlEyiZDjNIASqerCFok4piyC6NejKpou4DfKHzevMEc7bMQrvRLQhPnnpzJxds oarxOejSA/8QDkf3cAUfj81d78SULGhVf0VUgo1Se4olNm7wCFz+GLO3e+6PSXDB tu7KdYL/a8N8Iz293RsRfhGqN0J9dlYhcnEL1XQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=content-type:content-transfer-encoding :mime-version:from:to:cc:date:message-id:subject:in-reply-to :sender:list-id; s=arctest; t=1518326464; bh=Ts6MjaIPQ15Z9MRpeor O0Fz0R9QuqaXHMnbjD7P/p18=; b=TrLgmfG+gZeiO7DlZvsrs+66FxQtNxNisBp 4/LLmjJnXbjK6GhbKCnOuYdysoB6iS+VC44r3S8oLr1zJuQj+bwe4CGOpYRNZ0Ng miAMAmgVs+PyjvQfNgcdNOcHaDZlOre+kSvPnRfdkB006GFEjVuafCURpnI0VuzX 5fP/VWleVuxYTBN8qVzzMG1qkvbij7Wvl58oxW20GupuK/y7gILUz5xuyQEstIqb 52v0m+ZzC0AH1TtmJG8EaroPqNHO91eA9fQdtMtYNF2nVecxQ9fMZTuVjH2p2YAJ aLZLqjn9j50jDnNaURMr0bykhjuYzFswqtmKPwKcmUXPerz9V3A== ARC-Authentication-Results: i=1; mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Authentication-Results: mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932171AbeBKFSJ (ORCPT ); Sun, 11 Feb 2018 00:18:09 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:42726 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932162AbeBKFSH (ORCPT ); Sun, 11 Feb 2018 00:18:07 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Jan Harkes" , "Al Viro" Date: Sun, 11 Feb 2018 04:31:11 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 052/136] coda: fix 'kernel memory exposure attempt' in fsync In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 3.16.54-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jan Harkes commit d337b66a4c52c7b04eec661d86c2ef6e168965a2 upstream. When an application called fsync on a file in Coda a small request with just the file identifier was allocated, but the declared length was set to the size of union of all possible upcall requests. This bug has been around for a very long time and is now caught by the extra checking in usercopy that was introduced in Linux-4.8. The exposure happens when the Coda cache manager process reads the fsync upcall request at which point it is killed. As a result there is nobody servicing any further upcalls, trapping any processes that try to access the mounted Coda filesystem. Signed-off-by: Jan Harkes Signed-off-by: Al Viro Signed-off-by: Ben Hutchings --- fs/coda/upcall.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/fs/coda/upcall.c +++ b/fs/coda/upcall.c @@ -446,8 +446,7 @@ int venus_fsync(struct super_block *sb, UPARG(CODA_FSYNC); inp->coda_fsync.VFid = *fid; - error = coda_upcall(coda_vcp(sb), sizeof(union inputArgs), - &outsize, inp); + error = coda_upcall(coda_vcp(sb), insize, &outsize, inp); CODA_FREE(inp, insize); return error;