From owner-dev-commits-src-all@freebsd.org Wed Dec 23 16:17:44 2020 Return-Path: Delivered-To: dev-commits-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 558164C3DF7; Wed, 23 Dec 2020 16:17:44 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4D1JJm200Tz3Mjs; Wed, 23 Dec 2020 16:17:44 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 337B421091; Wed, 23 Dec 2020 16:17:44 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 0BNGHidH055164; Wed, 23 Dec 2020 16:17:44 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 0BNGHiuJ055163; Wed, 23 Dec 2020 16:17:44 GMT (envelope-from git) Date: Wed, 23 Dec 2020 16:17:44 GMT Message-Id: <202012231617.0BNGHiuJ055163@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: ace3d9475cee - ffs: Avoid out-of-bounds accesses in the fs_active bitmap MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: ace3d9475ceecd9bcb766bb82a1c8f87e8f560be Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: "Commit messages for all branches of the src repository." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 23 Dec 2020 16:17:44 -0000 The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=ace3d9475ceecd9bcb766bb82a1c8f87e8f560be commit ace3d9475ceecd9bcb766bb82a1c8f87e8f560be Author: Mark Johnston AuthorDate: 2020-12-23 16:13:00 +0000 Commit: Mark Johnston CommitDate: 2020-12-23 16:16:40 +0000 ffs: Avoid out-of-bounds accesses in the fs_active bitmap We use a bitmap to track which cylinder groups have changed between snapshot creation and filesystem suspension. The "legs" of the bitmap are four bytes wide (see ACTIVESET()) so we must round up the allocation size to a multiple of four bytes. I believe this bug is harmless since UMA/kmem_* will both pad the allocation and zero the full allocation. Note that malloc() does inline zeroing when the allocation size is known at compile-time. Reported by: pho (using KASAN) Reviewed by: kib, mckusick MFC after: 1 week Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D27731 --- sys/ufs/ffs/ffs_snapshot.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/sys/ufs/ffs/ffs_snapshot.c b/sys/ufs/ffs/ffs_snapshot.c index f224e828062b..201dbf6000de 100644 --- a/sys/ufs/ffs/ffs_snapshot.c +++ b/sys/ufs/ffs/ffs_snapshot.c @@ -385,8 +385,8 @@ restart: * touch up the few cylinder groups that changed during * the suspension period. */ - len = howmany(fs->fs_ncg, NBBY); - space = malloc(len, M_DEVBUF, M_WAITOK|M_ZERO); + len = roundup2(howmany(fs->fs_ncg, NBBY), sizeof(int)); + space = malloc(len, M_DEVBUF, M_WAITOK | M_ZERO); UFS_LOCK(ump); fs->fs_active = space; UFS_UNLOCK(ump);