On Tue, Jun 09, 2020 at 01:50:26PM +0200, Jan Kara wrote:
> On Tue 09-06-20 15:35:40, zhangyi (F) wrote:
> > In the ext4 filesystem with errors=panic, if one process is recording
> > errno in the superblock when invoking jbd2_journal_abort() due to some
> > error cases, it could be raced by another __ext4_abort() which is
> > setting the SB_RDONLY flag but missing panic because errno has not been
> > recorded.
> >
> > jbd2_journal_commit_transaction()
> > jbd2_journal_abort()
> > journal->j_flags |= JBD2_ABORT;
> > jbd2_journal_update_sb_errno()
> > | ext4_journal_check_start()
> > | __ext4_abort()
> > | sb->s_flags |= SB_RDONLY;
> > | if (!JBD2_REC_ERR)
> > | return;
> > journal->j_flags |= JBD2_REC_ERR;
> >
> > Finally, it will no longer trigger panic because the filesystem has
> > already been set read-only. Fix this by introduce j_abort_mutex to make
> > sure journal abort is completed before panic, and remove JBD2_REC_ERR
> > flag.
> >
> > Fixes: 4327ba52afd03 ("ext4, jbd2: ensure entering into panic after recording an error in superblock")
> > Signed-off-by: zhangyi (F) <yi.zhang@xxxxxxxxxx>
> > Cc: <stable@xxxxxxxxxxxxxxx>
>
> Great, thanks! The patch looks good to me. You can add:
>
> Reviewed-by: Jan Kara <jack@xxxxxxx>
Applied, thanks.
- Ted
