Re: ubifs mount failure

[Sascha Hauer]

On Tue, Dec 03, 2019 at 08:08:48PM +0100, Richard Weinberger wrote:
> On Tue, Dec 3, 2019 at 11:46 AM Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> wrote:
> >
> > On Tue, Dec 03, 2019 at 04:06:12PM +0530, naga suresh kumar wrote:
> > > Hi Richard,
> > >
> > > On Tue, Dec 3, 2019 at 2:40 PM Richard Weinberger <richard@xxxxxx> wrote:
> > > >
> > > > ----- Ursprüngliche Mail -----
> > > > > Von: "Naga Sureshkumar Relli" <nagasure@xxxxxxxxxx>
> > > > > https://elixir.bootlin.com/linux/v5.4/source/fs/ubifs/sb.c#L164
> > > > > we are trying to allocate 4325376 (~4MB)
> > > >
> > > > 4MiB? Is ->min_io_size that large?
> > > if you see https://elixir.bootlin.com/linux/latest/source/fs/ubifs/sb.c#L164
> > > The size is actually ALIGN(tmp, c->min_io_size).
> > > Here tmp is of 4325376 Bytes and min_io_size is 16384 Bytes
> >
> > 'tmp' contains bogus values. Try this:
> >
> > ----------------------------8<--------------------------------
> >
> > From 34f687fce189085f55706b4cddcb288a08f4ee06 Mon Sep 17 00:00:00 2001
> > From: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> > Date: Tue, 3 Dec 2019 11:41:20 +0100
> > Subject: [PATCH] ubifs: Fix wrong memory allocation
> >
> > In create_default_filesystem() when we allocate the idx node we must use
> > the idx_node_size we calculated just one line before, not tmp, which
> > contains completely other data.
> >
> > Fixes: c4de6d7e4319 ("ubifs: Refactor create_default_filesystem()")
> > Reported-by: Naga Sureshkumar Relli <nagasure@xxxxxxxxxx>
> > Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> > ---
> >  fs/ubifs/sb.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/fs/ubifs/sb.c b/fs/ubifs/sb.c
> > index a551eb3e9b89..6681c18e52b8 100644
> > --- a/fs/ubifs/sb.c
> > +++ b/fs/ubifs/sb.c
> > @@ -161,7 +161,7 @@ static int create_default_filesystem(struct ubifs_info *c)
> >         sup = kzalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_KERNEL);
> >         mst = kzalloc(c->mst_node_alsz, GFP_KERNEL);
> >         idx_node_size = ubifs_idx_node_sz(c, 1);
> > -       idx = kzalloc(ALIGN(tmp, c->min_io_size), GFP_KERNEL);
> > +       idx = kzalloc(ALIGN(idx_node_size, c->min_io_size), GFP_KERNEL);
> >         ino = kzalloc(ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size), GFP_KERNEL);
> >         cs = kzalloc(ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size), GFP_KERNEL);
> 
> Oh, looks good! Thanks for fixing, Sascha!

Will you apply this one? Otherwise I resend with the proper tags added.

Sascha

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