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From: Richard Weinberger <richard@nod.at>
To: Kees Cook <keescook@chromium.org>
Cc: Linux mtd <linux-mtd@lists.infradead.org>,
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        Silvio Cesare <silvio.cesare@gmail.com>,
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Subject: Re: [PATCH 1/2] Revert "UBIFS: Fix potential integer overflow in allocation"
Date: Mon, 02 Jul 2018 23:41:42 +0200
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Am Montag, 2. Juli 2018, 20:27:00 CEST schrieb Kees Cook:
> > Let's queue another patch for the next merge window which converts
> > kmalloc() -> kmalloc_array().
> 
> I'd prefer to leave it as-is for 4.18 because it would be the only
> unconverted kmalloc()-with-multiplication in the entire tree. We did
> treewide conversions and a revert would be undoing that here. (The
> scripts that check for this case would run "clean" for 4.18.)
> 
> So, this gets back to the question of the int vs u32: if you just
> didn't revert this patch, then the kmalloc_array() would stand too.
> Easy! :)

I can queue the kmalloc_array() conversion on top of the revert.
But TBH, using kmalloc_array() here is just ridiculous, we allocate
dn->size times 2 where dn->size is at most 4k.

Thanks,
//richard