On Sun 05-10-14 22:48:01, Ted Tso wrote: > The boot loader inode (inode #5) should never be visible in the > directory hierarchy, but it's possible if the file system is corrupted > that there will be a directory entry that points at inode #5. In > order to avoid accidentally trashing it, when such a directory inode > is opened, the inode will be marked as a bad inode, so that it's not > possible to modify (or read) the inode from userspace. > > Unfortunately, when we unlink this (invalid/illegal) directory entry, > we will put the bad inode on the ophan list, and then when try to > unlink the directory, we don't actually remove the bad inode from the > orphan list before freeing in-memory inode structure. This means the > in-memory orphan list is corrupted, leading to a kernel oops. > > In addition, avoid truncating a bad inode in ext4_destroy_inode(), > since truncating the boot loader inode is not a smart thing to do. > > Reported-by: Sami Liedes <sami.liedes@xxxxxx> > Signed-off-by: Theodore Ts'o <tytso@xxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx The patch looks good. You can add: Reviewed-by: Jan Kara <jack@xxxxxxx> Honza > --- > fs/ext4/inode.c | 7 +++---- > fs/ext4/namei.c | 2 +- > 2 files changed, 4 insertions(+), 5 deletions(-) > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index 41c4f97..59983b2 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -224,16 +224,15 @@ void ext4_evict_inode(struct inode *inode) > goto no_delete; > } > > - if (!is_bad_inode(inode)) > - dquot_initialize(inode); > + if (is_bad_inode(inode)) > + goto no_delete; > + dquot_initialize(inode); > > if (ext4_should_order_data(inode)) > ext4_begin_ordered_truncate(inode, 0); > truncate_inode_pages_final(&inode->i_data); > > WARN_ON(atomic_read(&EXT4_I(inode)->i_ioend_count)); > - if (is_bad_inode(inode)) > - goto no_delete; > > /* > * Protect us against freezing - iput() caller didn't have to have any > diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c > index 51705f8..a2a9d40 100644 > --- a/fs/ext4/namei.c > +++ b/fs/ext4/namei.c > @@ -2544,7 +2544,7 @@ int ext4_orphan_add(handle_t *handle, struct inode *inode) > int err = 0, rc; > bool dirty = false; > > - if (!sbi->s_journal) > + if (!sbi->s_journal || is_bad_inode(inode)) > return 0; > > WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && > -- > 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
