From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kara Subject: Re: [PATCH 2/2] ext4: add ext4_iget_normal() which is to be used for dir tree lookups Date: Mon, 6 Oct 2014 17:09:03 +0200 Message-ID: <20141006150903.GI7526@quack.suse.cz> References: <20141005001239.GD27150@sli.dy.fi> <1412563682-5720-1-git-send-email-tytso@mit.edu> <1412563682-5720-2-git-send-email-tytso@mit.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Ext4 Developers List To: Theodore Ts'o Return-path: Received: from cantor2.suse.de ([195.135.220.15]:54220 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753350AbaJFPJF (ORCPT ); Mon, 6 Oct 2014 11:09:05 -0400 Content-Disposition: inline In-Reply-To: <1412563682-5720-2-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: 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 > Signed-off-by: Theodore Ts'o > --- > 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@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Jan Kara SUSE Labs, CR