Re: [PATCH] RDMA/bnxt_re: fix a size calculation

[Jason Gunthorpe <jgg@ziepe.ca>]

On Thu, Jan 10, 2019 at 04:00:19PM +0300, Dan Carpenter wrote:
> This is from static analysis not from testing.  Depending on the value
> of rcfw->cmdq_depth, then this might not cause an issue at runtime.
> 
> The BITS_TO_LONGS() macro tells us how many longs it take to hold a
> bitmap.  In other words, it divides by the number if bits per long and
> rounds up.  Then we want to take that number and multiple by
> sizeof(long) to get the number of bytes to allocate.
> 
> The code here does the multiplication first so the rounding up is done
> in the wrong place.  So imagine we want to allocate 1 bit, then
> "(1 * 8) / 64 = 1" when we round up.  But it should be
> "(1 / 64) * 8 = 8".  In other words, because of the rounding difference
> we might allocate up to "sizeof(long) - 1" bytes fewer than intended.
> 
> Fixes: 1ac5a4047975 ("RDMA/bnxt_re: Add bnxt_re RoCE driver")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> Acked-By: Devesh Sharma <devesh.sharma@broadcom.com>
> ---
>  drivers/infiniband/hw/bnxt_re/qplib_rcfw.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)

Applied to for-next

Thanks,
Jason