[PATCH] nvme-pci: Fix mempool alloc size

[Chaitanya Kulkarni]

On 12/19/22 10:59, Keith Busch wrote:
> From: Keith Busch <kbusch at kernel.org>
> 
> Convert the max size to bytes to match the units of the divisor that
> calculates the worst-case number of PRP entries.
> 
> The result is used to determine how many PRP Lists are required. The
> code was previously rounding this to 1 list, but we can require 2 in the
> worst case. In that scenario, the driver would corrupt memory beyond the
> size provided by the mempool.
> 
> While unlikely to occur (you'd need a 4MB in exactly 127 phys segments
> on a queue that doesn't support SGLs), this memory corruption has been
> observed by kfence.
> 
> Cc: Jens Axboe <axboe at kernel.dk>
> Fixes: 943e942e6266f ("nvme-pci: limit max IO size and segments to avoid high order allocations")
> Signed-off-by: Keith Busch <kbusch at kernel.org>
> ---

hmm, surprising to see that we never caught this until today...

Reviewed-by: Chaitanya Kulkarni <kch at nvidia.com>

-ck