[PATCH 3.18+] b43: fix NULL pointer dereference in b43_phy_copy()

[Rafał Miłecki]

On 5 November 2014 23:31, Hauke Mehrtens <hauke at hauke-m.de> wrote:
> phy_read and phy_write are not set for every phy any more sine this:
> commit d342b95dd735014a590f9051b1ba227eb54ca8f6
> Author: Rafał Miłecki <zajec5 at gmail.com>
> Date:   Thu Jul 31 21:59:43 2014 +0200
>
>     b43: don't duplicate common PHY read/write ops
>
> b43_phy_copy() accesses phy_read and phy_write directly and will fail
> with some phys. This patch fixes the regression by using the
> b43_phy_read() and b43_phy_write() functions which should be used for
> read and write access.
>
> This should fix this bug report:
> https://bugzilla.kernel.org/show_bug.cgi?id=87731
>
> Reported-by: Volker Kempter <v.kempter at pe.tu-clausthal.de>
> Signed-off-by: Hauke Mehrtens <hauke at hauke-m.de>
> ---
>  drivers/net/wireless/b43/phy_common.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> This should go into wireless-testing and into 3.18 as it fixes a
> regression in 3.18.
>
> diff --git a/drivers/net/wireless/b43/phy_common.c b/drivers/net/wireless/b43/phy_common.c
> index 1dfc682..3f37401 100644
> --- a/drivers/net/wireless/b43/phy_common.c
> +++ b/drivers/net/wireless/b43/phy_common.c
> @@ -301,8 +301,7 @@ void b43_phy_write(struct b43_wldev *dev, u16 reg, u16 value)
>  void b43_phy_copy(struct b43_wldev *dev, u16 destreg, u16 srcreg)
>  {
>         assert_mac_suspended(dev);
> -       dev->phy.ops->phy_write(dev, destreg,
> -               dev->phy.ops->phy_read(dev, srcreg));
> +       b43_phy_write(dev, destreg, b43_phy_read(dev, srcreg));
>  }

Could you drop the assert_mac_suspended? We do it already in both:
phy_read and phy_write.