From: Jerry Ray jerry.ray@microchip.com
[ Upstream commit fef5de753ff01887cfa50990532c3890fccb9338 ]
Issue found during code review. This bug has no impact as long as the ks8851_net structure is the first element of the ks8851_net_spi structure. As long as the offset to the ks8851_net struct is zero, the container_of() macro is subtracting 0 and therefore no damage done. But if the ks8851_net_spi struct is ever modified such that the ks8851_net struct within it is no longer the first element of the struct, then the bug would manifest itself and cause problems.
struct ks8851_net is contained within ks8851_net_spi. ks is contained within kss. kss is the priv_data of the netdev structure.
Signed-off-by: Jerry Ray jerry.ray@microchip.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/micrel/ks8851_spi.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/micrel/ks8851_spi.c b/drivers/net/ethernet/micrel/ks8851_spi.c index 4ec7f1615977..8327e7f30476 100644 --- a/drivers/net/ethernet/micrel/ks8851_spi.c +++ b/drivers/net/ethernet/micrel/ks8851_spi.c @@ -415,7 +415,8 @@ static int ks8851_probe_spi(struct spi_device *spi)
spi->bits_per_word = 8;
- ks = netdev_priv(netdev); + kss = netdev_priv(netdev); + ks = &kss->ks8851;
ks->lock = ks8851_lock_spi; ks->unlock = ks8851_unlock_spi; @@ -435,8 +436,6 @@ static int ks8851_probe_spi(struct spi_device *spi) IRQ_RXPSI) /* RX process stop */ ks->rc_ier = STD_IRQ;
- kss = to_ks8851_spi(ks); - kss->spidev = spi; mutex_init(&kss->lock); INIT_WORK(&kss->tx_work, ks8851_tx_work);