From owner-svn-src-head@freebsd.org Sat Jul 1 20:25:23 2017 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 7ED3ED91B76; Sat, 1 Jul 2017 20:25:23 +0000 (UTC) (envelope-from allanjude@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4C66A70A56; Sat, 1 Jul 2017 20:25:23 +0000 (UTC) (envelope-from allanjude@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v61KPMBw094741; Sat, 1 Jul 2017 20:25:22 GMT (envelope-from allanjude@FreeBSD.org) Received: (from allanjude@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id v61KPMkh094740; Sat, 1 Jul 2017 20:25:22 GMT (envelope-from allanjude@FreeBSD.org) Message-Id: <201707012025.v61KPMkh094740@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: allanjude set sender to allanjude@FreeBSD.org using -f From: Allan Jude Date: Sat, 1 Jul 2017 20:25:22 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r320553 - head/sys/boot/efi/libefi X-SVN-Group: head X-SVN-Commit-Author: allanjude X-SVN-Commit-Paths: head/sys/boot/efi/libefi X-SVN-Commit-Revision: 320553 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 01 Jul 2017 20:25:23 -0000 Author: allanjude Date: Sat Jul 1 20:25:22 2017 New Revision: 320553 URL: https://svnweb.freebsd.org/changeset/base/320553 Log: Integer underflow in efipart_realstrategy when I/O starts after end of disk This fixes an integer underflow in efipart_realstrategy, which causes crashes when an I/O operation's start point is after the end of the disk. This can happen when trying to detect filesystems on very small disks. This can occur if a BIOS freebsd-boot partition exists on a system when the EFI loader is being used. PR: 219000 Submitted by: Eric McCorkle Reviewed by: cem (previous version), tsoome (previous version) MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D10559 Modified: head/sys/boot/efi/libefi/efipart.c Modified: head/sys/boot/efi/libefi/efipart.c ============================================================================== --- head/sys/boot/efi/libefi/efipart.c Sat Jul 1 20:08:45 2017 (r320552) +++ head/sys/boot/efi/libefi/efipart.c Sat Jul 1 20:25:22 2017 (r320553) @@ -888,6 +888,7 @@ efipart_realstrategy(void *devdata, int rw, daddr_t bl char *blkbuf; size_t blkoff, blksz; int error; + size_t diskend, readstart; if (dev == NULL || blk < 0) return (EINVAL); @@ -925,7 +926,15 @@ efipart_realstrategy(void *devdata, int rw, daddr_t bl /* make sure we don't read past disk end */ if ((off + size) / blkio->Media->BlockSize > d_offset + disk_blocks) { - size = d_offset + disk_blocks - off / blkio->Media->BlockSize; + diskend = d_offset + disk_blocks; + readstart = off / blkio->Media->BlockSize; + + if (diskend <= readstart) { + *rsize = 0; + + return (EIO); + } + size = diskend - readstart; size = size * blkio->Media->BlockSize; }