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From:   Kees Cook <keescook@chromium.org>
Date:   Fri, 5 Oct 2018 17:04:16 -0700
Message-ID: <CAGXu5jJfs0KpRa6yag=ud0sJVW-tM-E4xuvgCMnBdFfDck5E1g@mail.gmail.com>
Subject: Re: [PATCH v4.19-rc7] treewide: Replace more open-coded allocation
 size multiplications
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     LKML <linux-kernel@vger.kernel.org>
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On Fri, Oct 5, 2018 at 4:51 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Fri, Oct 05, 2018 at 04:35:59PM -0700, Kees Cook wrote:
>> As done treewide earlier, this catches several more open-coded
>> allocation size calculations that were added to the kernel during the
>> merge window. This performs the following mechanical transformations
>> using Coccinelle:
>>
>>       kvmalloc(a * b, ...) -> kvmalloc_array(a, b, ...)
>>       kvzalloc(a * b, ...) -> kvcalloc(a, b, ...)
>>       devm_kzalloc(..., a * b, ...) -> devm_kcalloc(..., a, b, ...)
>>
>> Signed-off-by: Kees Cook <keescook@chromium.org>
>
> Has this had any testing in linux-next?

No; they're mechanical transformations (though I did build test them).
If you want I could add this to linux-next for a week?

> And when was "earlier"?

v4.18, when all of these were originally eliminated:

026f05079b00 treewide: Use array_size() in f2fs_kzalloc()
c86065938aab treewide: Use array_size() in f2fs_kmalloc()
76e43e37a407 treewide: Use array_size() in sock_kmalloc()
84ca176bf54a treewide: Use array_size() in kvzalloc_node()
fd7becedb1f0 treewide: Use array_size() in vzalloc_node()
fad953ce0b22 treewide: Use array_size() in vzalloc()
42bc47b35320 treewide: Use array_size() in vmalloc()
a86854d0c599 treewide: devm_kzalloc() -> devm_kcalloc()
3c4211ba8ad8 treewide: devm_kmalloc() -> devm_kmalloc_array()
778e1cdd81bb treewide: kvzalloc() -> kvcalloc()
344476e16acb treewide: kvmalloc() -> kvmalloc_array()
590b5b7d8671 treewide: kzalloc_node() -> kcalloc_node()
6396bb221514 treewide: kzalloc() -> kcalloc()
6da2ec56059c treewide: kmalloc() -> kmalloc_array()

The new patch is catching new open-coded multiplications introduced in v4.19.

-Kees

-- 
Kees Cook
Pixel Security