From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754766AbbFQWtq (ORCPT ); Wed, 17 Jun 2015 18:49:46 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:35695 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751700AbbFQWaQ (ORCPT ); Wed, 17 Jun 2015 18:30:16 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Ryusuke Konishi , Andrew Morton , Linus Torvalds , Kamal Mostafa Subject: [PATCH 3.13.y-ckt 052/122] nilfs2: fix sanity check of btree level in nilfs_btree_root_broken() Date: Wed, 17 Jun 2015 15:27:59 -0700 Message-Id: <1434580149-3095-53-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1434580149-3095-1-git-send-email-kamal@canonical.com> References: <1434580149-3095-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.13.11-ckt22 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Ryusuke Konishi commit d8fd150fe3935e1692bf57c66691e17409ebb9c1 upstream. The range check for b-tree level parameter in nilfs_btree_root_broken() is wrong; it accepts the case of "level == NILFS_BTREE_LEVEL_MAX" even though the level is limited to values in the range of 0 to (NILFS_BTREE_LEVEL_MAX - 1). Since the level parameter is read from storage device and used to index nilfs_btree_path array whose element count is NILFS_BTREE_LEVEL_MAX, it can cause memory overrun during btree operations if the boundary value is set to the level parameter on device. This fixes the broken sanity check and adds a comment to clarify that the upper bound NILFS_BTREE_LEVEL_MAX is exclusive. Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Kamal Mostafa --- fs/nilfs2/btree.c | 2 +- include/linux/nilfs2_fs.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/nilfs2/btree.c b/fs/nilfs2/btree.c index ecdbae1..090d8ce 100644 --- a/fs/nilfs2/btree.c +++ b/fs/nilfs2/btree.c @@ -388,7 +388,7 @@ static int nilfs_btree_root_broken(const struct nilfs_btree_node *node, nchildren = nilfs_btree_node_get_nchildren(node); if (unlikely(level < NILFS_BTREE_LEVEL_NODE_MIN || - level > NILFS_BTREE_LEVEL_MAX || + level >= NILFS_BTREE_LEVEL_MAX || nchildren < 0 || nchildren > NILFS_BTREE_ROOT_NCHILDREN_MAX)) { pr_crit("NILFS: bad btree root (inode number=%lu): level = %d, flags = 0x%x, nchildren = %d\n", diff --git a/include/linux/nilfs2_fs.h b/include/linux/nilfs2_fs.h index 9875576..1108aca 100644 --- a/include/linux/nilfs2_fs.h +++ b/include/linux/nilfs2_fs.h @@ -458,7 +458,7 @@ struct nilfs_btree_node { /* level */ #define NILFS_BTREE_LEVEL_DATA 0 #define NILFS_BTREE_LEVEL_NODE_MIN (NILFS_BTREE_LEVEL_DATA + 1) -#define NILFS_BTREE_LEVEL_MAX 14 +#define NILFS_BTREE_LEVEL_MAX 14 /* Max level (exclusive) */ /** * struct nilfs_palloc_group_desc - block group descriptor -- 1.9.1