[PATCH AUTOSEL 5.6 16/47] net: bmac: Fix read of MAC address from ROM

Sasha Levin
2020-05-28T12:10:26Z

From: Jeremy Kerr <jk@ozlabs.org>

[ Upstream commit ef01cee2ee1b369c57a936166483d40942bcc3e3 ]

In bmac_get_station_address, We're reading two bytes at a time from ROM,
but we do that six times, resulting in 12 bytes of read & writes. This
means we will write off the end of the six-byte destination buffer.

This change fixes the for-loop to only read/write six bytes.

Based on a proposed fix from Finn Thain <fthain@telegraphics.com.au>.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Reported-by: Stan Johnson <userm57@yahoo.com>
Tested-by: Stan Johnson <userm57@yahoo.com>
Reported-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/apple/bmac.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/apple/bmac.c b/drivers/net/ethernet/apple/bmac.c
index a58185b1d8bf..3e3711b60d01 100644
--- a/drivers/net/ethernet/apple/bmac.c
+++ b/drivers/net/ethernet/apple/bmac.c
@@ -1182,7 +1182,7 @@ bmac_get_station_address(struct net_device *dev, unsigned char *ea)
int i;
unsigned short data;

- for (i = 0; i < 6; i++)
+ for (i = 0; i < 3; i++)
{
reset_and_select_srom(dev);
data = read_srom(dev, i + EnetAddressOffset/2, SROMAddressBits);
--
2.25.1