From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754440AbbIOJJu (ORCPT ); Tue, 15 Sep 2015 05:09:50 -0400 Received: from mail.kernel.org ([198.145.29.136]:52684 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754414AbbIOJJr (ORCPT ); Tue, 15 Sep 2015 05:09:47 -0400 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Ryusuke Konishi , Andrew Morton , Linus Torvalds , Zefan Li Subject: [PATCH 3.4 078/146] nilfs2: fix sanity check of btree level in nilfs_btree_root_broken() Date: Tue, 15 Sep 2015 17:03:13 +0800 Message-Id: <1442307861-32031-78-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1442307787-31952-1-git-send-email-lizf@kernel.org> References: <1442307787-31952-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ryusuke Konishi 3.4.109-rc1 review patch. If anyone has any objections, please let me know. ------------------ 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: Zefan Li --- 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 89bd4a4..25c6891 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