On Wed 24-10-12 16:12:44, Ashish Sangwan wrote:
> During orphan cleanup while doing truncate, if we fail to obtain journal
> handle, the inode for which truncate was called would not be removed from
> both the on-disk and in-memory orphan lists as the call to ext3_orphan_del
> would not be executed.
>
> This would have following consequences:
> a) As the inode is not removed from the on-disk list, truncate would be
> called again for the same inode. Each call would add the inode to the
> in-memory list. This operation would continue endlessly or until truncate
> is succeed.
>
> b) If somehow, after some iterations, truncate is succeed, ext3_orphan_del
> will only remove the inode from in-memory list just 1 time. This will trigger
> j_assert during put super.
>
> This patch handles both the problems. If truncate fails, first in-memory
> list is cleared and than the partition is mounted as read only.
> Failure to obtain journal handle during mount may suggest that journal
> device is corrupted.
Could you really trigger any of the described bugs? Because
ext3_truncate() does take care to remove inode from orphan list even if
starting of a transaction fails (see out_notrans label in ext3_truncate()).
Also spitting additional messages should be unnecessary - the error which
caused truncate to fail should have logged the error message and also taken
appropriate action depending on filesystem configuration (i.e., remount fs
read-only, panic the system, or do nothing).
Honza
>
> Signed-off-by: Ashish Sangwan <ashish.sangwan2@xxxxxxxxx>
> Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxx>
> ---
> fs/ext3/super.c | 17 ++++++++++++++++-
> 1 file changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/fs/ext3/super.c b/fs/ext3/super.c
> index bd60e08..798cd6f 100644
> --- a/fs/ext3/super.c
> +++ b/fs/ext3/super.c
> @@ -1540,7 +1540,22 @@ static void ext3_orphan_cleanup (struct super_block * sb,
> jbd_debug(2, "truncating inode %lu to %Ld bytes\n",
> inode->i_ino, inode->i_size);
> ext3_truncate(inode);
> - nr_truncates++;
> + if (list_empty(&EXT3_I(inode)->i_orphan)) {
> + nr_truncates++;
> + } else {
> + /* Remove inode from in-memory orphan list */
> + list_del_init(&EXT3_I(inode)->i_orphan);
> + ext3_msg(sb, KERN_ERR, "Truncate failed for "
> + "orphan inode = %lu. Running e2fsck"
> + " is recommended", inode->i_ino);
> + if (!(s_flags & MS_RDONLY)) {
> + ext3_msg(sb, KERN_INFO, "FS would be"
> + " mounted as readonly");
> + s_flags |= MS_RDONLY;
> + }
> + break;
> + }
> +
> } else {
> printk(KERN_DEBUG
> "%s: deleting unreferenced inode %lu\n",
> --
> 1.7.11.4
>
--
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
