UBIFS-AUTH panic after reboot

[Richard Weinberger]

On Mon, Sep 21, 2020 at 12:46 PM Kristof Havasi <havasiefr at gmail.com> wrote:
>
> On Mon, 21 Sep 2020 at 11:51, Richard Weinberger <richard at nod.at> wrote:
> >
> > ----- Ursprüngliche Mail -----
> > >> > Does the problem also trigger with encryption disabled? So just with
> > >> > authentication?
> > > I couldn't trigger the same error with encryption disabled and authentication
> > > enabled. Even if I enabled all the chk_* knobs under kernel/debug/ubifs/, no
> > > failed assertion or error/warning log could be observed.
> >
> > So, with either encryption or authentication enabled everything is fine
> > but when both are enabled you hit the problem?
> > Interesting.
>
> That is exactly what I can observe.
>
> >
> > >> Does it print big LPT or small LPT model?
> > >
> > > small LPT model.
> >
> > I'll try to reproduce now on a similar sized NAND. :-)
>
> I mentioned that I use the buildroot's mkfs.ubifs with customization,
> but here are the parameters:
> (Configured via Kconfig)
>
> --max-leb-cnt=3968
> --min-io-size=0x1000
> --leb-size=0x3E000
> --key /path/to/key
> --key-descriptor dead12345678beef
> --cipher AES-256-XTS
> --hash-algo sha256
> --auth-key="pkcs11:token=..."
>
> The flash is a Micron MT29F8G08ABACAWP-IT:C which has 224 bytes OOB,
> which is not
> included in the --min-io-size. That is ok, isn't?

Yes. Both UBI and UBIFS don't use OOB.

I think I've found the problem. Can you please test the following change?

diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c
index 4a5b06f8d812..869ef6efa48f 100644
--- a/fs/ubifs/journal.c
+++ b/fs/ubifs/journal.c
@@ -936,8 +936,6 @@ int ubifs_jnl_write_inode(struct ubifs_info *c,
const struct inode *inode)
                                          inode->i_ino);
        release_head(c, BASEHD);

-       ubifs_add_auth_dirt(c, lnum);
-
        if (last_reference) {
                err = ubifs_tnc_remove_ino(c, inode->i_ino);
                if (err)
@@ -947,6 +945,8 @@ int ubifs_jnl_write_inode(struct ubifs_info *c,
const struct inode *inode)
        } else {
                union ubifs_key key;

+               ubifs_add_auth_dirt(c, lnum);
+
                ino_key_init(c, &key, inode->i_ino);
                err = ubifs_tnc_add(c, &key, lnum, offs, ilen, hash);
        }

A few lines before in the we last_reference call ubifs_add_dirt(c,
lnum, write_len) and write_len contains
already the auth node size. So the auth node size is accounted twice.
Please let me know whether it helps, I think ubifs_jnl_write_inode()
needs more cleanup.

-- 
Thanks,
//richard