On Sun 05-10-14 22:48:02, Ted Tso wrote:
> If there is a corrupted file system which has directory entries that
> point at reserved, metadata inodes, prohibit them from being used by
> treating them the same way we treat Boot Loader inodes --- that is,
> mark them to be bad inodes. This prohibits them from being opened,
> deleted, or modified via chmod, chown, utimes, etc.
>
> In particular, this prevents a corrupted file system which has a
> directory entry which points at the journal inode from being deleted
> and being released, after which point Much Hilarity Ensues.
>
> Reported-by: Sami Liedes <sami.liedes@xxxxxx>
> Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
> ---
> fs/ext4/ext4.h | 1 +
> fs/ext4/inode.c | 10 ++++++++++
> fs/ext4/namei.c | 4 ++--
> fs/ext4/super.c | 2 +-
> 4 files changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index 1eb5b7b..012e89b 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -2109,6 +2109,7 @@ int do_journal_get_write_access(handle_t *handle,
> #define CONVERT_INLINE_DATA 2
>
> extern struct inode *ext4_iget(struct super_block *, unsigned long);
> +extern struct inode *ext4_iget_normal(struct super_block *, unsigned long);
> extern int ext4_write_inode(struct inode *, struct writeback_control *);
> extern int ext4_setattr(struct dentry *, struct iattr *);
> extern int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 59983b2..437622c 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -4104,6 +4104,16 @@ bad_inode:
> return ERR_PTR(ret);
> }
>
> +struct inode *ext4_iget_normal(struct super_block *sb, unsigned long ino)
> +{
> + struct inode *ret_inode = ext4_iget(sb, ino);
> +
> + if (ret_inode && !IS_ERR(ret_inode) &&
> + ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
> + make_bad_inode(ret_inode);
> + return ret_inode;
Hum, why don't we just return an error (like EIO) when invalid inode
number is passed?
Honza
> +}
> +
> static int ext4_inode_blocks_set(handle_t *handle,
> struct ext4_inode *raw_inode,
> struct ext4_inode_info *ei)
> diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
> index a2a9d40..7037ecf 100644
> --- a/fs/ext4/namei.c
> +++ b/fs/ext4/namei.c
> @@ -1417,7 +1417,7 @@ static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsi
> dentry);
> return ERR_PTR(-EIO);
> }
> - inode = ext4_iget(dir->i_sb, ino);
> + inode = ext4_iget_normal(dir->i_sb, ino);
> if (inode == ERR_PTR(-ESTALE)) {
> EXT4_ERROR_INODE(dir,
> "deleted inode referenced: %u",
> @@ -1450,7 +1450,7 @@ struct dentry *ext4_get_parent(struct dentry *child)
> return ERR_PTR(-EIO);
> }
>
> - return d_obtain_alias(ext4_iget(child->d_inode->i_sb, ino));
> + return d_obtain_alias(ext4_iget_normal(child->d_inode->i_sb, ino));
> }
>
> /*
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 1070d6e..a0811cc 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -1001,7 +1001,7 @@ static struct inode *ext4_nfs_get_inode(struct super_block *sb,
> * Currently we don't know the generation for parent directory, so
> * a generation of 0 means "accept any"
> */
> - inode = ext4_iget(sb, ino);
> + inode = ext4_iget_normal(sb, ino);
> if (IS_ERR(inode))
> return ERR_CAST(inode);
> if (generation && inode->i_generation != generation) {
> --
> 2.1.0
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Jan Kara <jack@xxxxxxx>
SUSE Labs, CR
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
