Re: [PATCH openEuler-22.03-LTS] nilfs2: fix NULL pointer dereference at nilfs_bmap_lookup_at_level()

[Long Li <leo.lilong@huawei.com>]

On Tue, Nov 01, 2022 at 07:43:37PM +0800, Long Li wrote:
> From: Ryusuke Konishi <konishi.ryusuke@gmail.com>
> 
> mainline inclusion
> from mainline-v6.0-rc3
> commit 21a87d88c2253350e115029f14fe2a10a7e6c856
> category: bugfix
> bugzilla: https://gitee.com/src-openeuler/kernel/issues/I5X1Z4
> CVE: CVE-2022-3621
> 
> Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=21a87d88c2253350e115029f14fe2a10a7e6c856
> 
> --------------------------------
> 
> If the i_mode field in inode of metadata files is corrupted on disk, it
> can cause the initialization of bmap structure, which should have been
> called from nilfs_read_inode_common(), not to be called.  This causes a
> lockdep warning followed by a NULL pointer dereference at
> nilfs_bmap_lookup_at_level().
> 
> This patch fixes these issues by adding a missing sanitiy check for the
> i_mode field of metadata file's inode.
> 
> Link: https://lkml.kernel.org/r/20221002030804.29978-1-konishi.ryusuke@gmail.com
> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
> Reported-by: syzbot+2b32eb36c1a825b7a74c@syzkaller.appspotmail.com
> Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Long Li <leo.lilong@huawei.com>
> ---
>  fs/nilfs2/inode.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
> index ca380c6d7825..bfe3c7ccdf50 100644
> --- a/fs/nilfs2/inode.c
> +++ b/fs/nilfs2/inode.c
> @@ -462,6 +462,8 @@ int nilfs_read_inode_common(struct inode *inode,
>  	inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
>  	inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec);
>  	inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
> +	if (nilfs_is_metadata_file_inode(inode) && !S_ISREG(inode->i_mode))
> +		return -EIO; /* this inode is for metadata and corrupted */
>  	if (inode->i_nlink == 0)
>  		return -ESTALE; /* this inode is deleted */
>  
> -- 
> 2.31.1
> 

Please skip this email, I made a mistake in my email, I'm very sorry
for my misoperation.