From: Theodore Ts'o Subject: [PATCH FOR-STABLE-2.6.28 21/24] ext4: only use i_size_high for regular files Date: Tue, 17 Feb 2009 10:32:39 -0500 Message-ID: <1234884762-13580-22-git-send-email-tytso@mit.edu> References: <1234884762-13580-1-git-send-email-tytso@mit.edu> <1234884762-13580-2-git-send-email-tytso@mit.edu> <1234884762-13580-3-git-send-email-tytso@mit.edu> <1234884762-13580-4-git-send-email-tytso@mit.edu> <1234884762-13580-5-git-send-email-tytso@mit.edu> <1234884762-13580-6-git-send-email-tytso@mit.edu> <1234884762-13580-7-git-send-email-tytso@mit.edu> <1234884762-13580-8-git-send-email-tytso@mit.edu> <1234884762-13580-9-git-send-email-tytso@mit.edu> <1234884762-13580-10-git-send-email-tytso@mit.edu> <1234884762-13580-11-git-send-email-tytso@mit.edu> <1234884762-13580-12-git-send-email-tytso@mit.edu> <1234884762-13580-13-git-send-email-tytso@mit.edu> <1234884762-13580-14-git-send-email-tytso@mit.edu> <1234884762-13580-15-git-send-email-tytso@mit.edu> <1234884762-13580-16-git-send-email-tytso@mit.edu> <1234884762-13580-17-git-send-email-tytso@mit.edu> <1234884762-13580-18-git-send-email-tytso@mit.edu> <1234884762-13580-19-git-send-email-tytso@mit.edu> <1234884762-13580-20-git-send-email-tytso@mit.edu> <1234884762-13580-21-git-send-email-tytso@mit.edu> Cc: linux-ext4@vger.kernel.org, Theodore Ts'o To: stable@kernel.org Return-path: Received: from thunk.org ([69.25.196.29]:54657 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752630AbZBQQDh (ORCPT ); Tue, 17 Feb 2009 11:03:37 -0500 In-Reply-To: <1234884762-13580-21-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: Directories are not allowed to be bigger than 2GB, so don't use i_size_high for anything other than regular files. E2fsck should complain about these inodes, but the simplest thing to do for the kernel is to only use i_size_high for regular files. This prevents an intentially corrupted filesystem from causing the kernel to burn a huge amount of CPU and issuing error messages such as: EXT4-fs warning (device loop0): ext4_block_to_path: block 135090028 > max Thanks to David Maciejak from Fortinet's FortiGuard Global Security Research Team for reporting this issue. http://bugzilla.kernel.org/show_bug.cgi?id=12375 Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org (cherry picked from commit 06a279d636734da32bb62dd2f7b0ade666f65d7c) --- fs/ext4/ext4.h | 7 +++++-- fs/ext4/inode.c | 4 ++-- 2 files changed, 7 insertions(+), 4 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 4b73ac1..dfccef5 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1188,8 +1188,11 @@ static inline void ext4_r_blocks_count_set(struct ext4_super_block *es, static inline loff_t ext4_isize(struct ext4_inode *raw_inode) { - return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) | - le32_to_cpu(raw_inode->i_size_lo); + if (S_ISREG(le16_to_cpu(raw_inode->i_mode))) + return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) | + le32_to_cpu(raw_inode->i_size_lo); + else + return (loff_t) le32_to_cpu(raw_inode->i_size_lo); } static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 008c4b0..ccb6947 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -351,9 +351,9 @@ static int ext4_block_to_path(struct inode *inode, final = ptrs; } else { ext4_warning(inode->i_sb, "ext4_block_to_path", - "block %lu > max", + "block %lu > max in inode %lu", i_block + direct_blocks + - indirect_blocks + double_blocks); + indirect_blocks + double_blocks, inode->i_ino); } if (boundary) *boundary = final - 1 - (i_block & (ptrs - 1)); -- 1.5.6.3