Subject: Re: [PATCH] i40e{,vf}: Fix out-of-bound cpumask read in IRQ affinity handler

From: Stefano Brivio <[email-masked]>
Date: Tue, 15 Aug 2017 12:33:48 +0200

On Tue, 15 Aug 2017 12:30:14 +0200
Stefano Brivio <[email-masked]> wrote:

> The cpumask used in i40e{,vf}_irq_affinity_notify() is allocated
> by irq_affinity_notify() with alloc_cpumask_var(), which doesn't
> allocate NR_CPUS bits, but only nr_cpumask_bits bits. If we just
> dereference it, we'll read way more than what is allocated, e.g.
> 1024 bytes vs. 8 bytes allocated on x86_64 machine with 24 CPUs.

Sorry, just two minutes after sending this I noticed Juergen submitted
the same fixes on Saturday:

From: Juergen Gross <[email-masked]>
To: [email-masked], [email-masked],         [email-masked]
Cc: [email-masked], Juergen Gross <[email-masked]>,         [email-masked]
Subject: [PATCH] net/i40e: use cpumask_copy() for assigning cpumask
Date: Sat, 12 Aug 2017 18:09:46 +0200

Please discard.