From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:45816 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752522AbcCAXrA (ORCPT ); Tue, 1 Mar 2016 18:47:00 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kees Cook , Jens Axboe Subject: [PATCH 3.10 31/80] mac: validate mac_partition is within sector Date: Tue, 1 Mar 2016 15:45:25 -0800 Message-Id: <20160301234350.654122124@linuxfoundation.org> In-Reply-To: <20160301234349.667990420@linuxfoundation.org> References: <20160301234349.667990420@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kees Cook commit 02e2a5bfebe99edcf9d694575a75032d53fe1b73 upstream. If md->signature == MAC_DRIVER_MAGIC and md->block_size == 1023, a single 512 byte sector would be read (secsize / 512). However the partition structure would be located past the end of the buffer (secsize % 512). Signed-off-by: Kees Cook Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- block/partitions/mac.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) --- a/block/partitions/mac.c +++ b/block/partitions/mac.c @@ -32,7 +32,7 @@ int mac_partition(struct parsed_partitio Sector sect; unsigned char *data; int slot, blocks_in_map; - unsigned secsize; + unsigned secsize, datasize, partoffset; #ifdef CONFIG_PPC_PMAC int found_root = 0; int found_root_goodness = 0; @@ -50,10 +50,14 @@ int mac_partition(struct parsed_partitio } secsize = be16_to_cpu(md->block_size); put_dev_sector(sect); - data = read_part_sector(state, secsize/512, §); + datasize = round_down(secsize, 512); + data = read_part_sector(state, datasize / 512, §); if (!data) return -1; - part = (struct mac_partition *) (data + secsize%512); + partoffset = secsize % 512; + if (partoffset + sizeof(*part) > datasize) + return -1; + part = (struct mac_partition *) (data + partoffset); if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC) { put_dev_sector(sect); return 0; /* not a MacOS disk */