[U-Boot] [PATCH v2] net, phy, cpsw: fix NULL pointer deference

Heiko Schocher
2013-09-05T06:05:22Z

if phy_connect() did not find a phy, phydev is NULL and
following code in cpsw_phy_init() crashes. Fix this.

Signed-off-by: Heiko Schocher <hs@denx.de>
Cc: Joe Hershberger <joe.hershberger@gmail.com>
Cc: Mugunthan V N <mugunthanvnm@ti.com>
Cc: Tom Rini <trini@ti.com>

---
- changes for v2:
- change commit message as it is a NULL pointer deference error
not an unaligned access problem, as Tom Rini mentioned
- fix more places in the driver with NULL pointer problem

Found on the dxr2 board with no phy connected to the board,
U-Boot crashes with:

U-Boot 2013.07-12701-gea98378-dirty (Sep 04 2013 - 06:58:16)

I2C: ready
DRAM: 128 MiB
Enable d-cache
FactorySet is not right in eeprom.
NAND: 256 MiB
MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1
8-bit BCH HW ECC selected
Net: Could not get PHY for cpsw: addr 0
data abort

MAYBE you should read doc/README.arm-unaligned-accesses

pc : [<87f80574>] lr : [<87f80fcc>]
sp : 86f5aee0 ip : 00000034 fp : 80100020
r10: 00000014 r9 : 07e5d000 r8 : 86f5af30
r7 : 86f5f750 r6 : 86f5f804 r5 : 86f5f708 r4 : 86f5f750
r3 : 00000000 r2 : 00000000 r1 : 87fa4d08 r0 : 00000000
Flags: nZCv IRQs off FIQs on Mode SVC_32
Resetting CPU ...
---
drivers/net/cpsw.c | 26 +++++++++++++++++++++++++-
1 Datei ge?ndert, 25 Zeilen hinzugef?gt(+), 1 Zeile entfernt(-)

diff --git a/drivers/net/cpsw.c b/drivers/net/cpsw.c
index 9bab71a..186665b 100644
--- a/drivers/net/cpsw.c
+++ b/drivers/net/cpsw.c
@@ -561,6 +561,9 @@ static inline void setbit_and_wait_for_clear32(void *addr)
static void cpsw_set_slave_mac(struct cpsw_slave *slave,
struct cpsw_priv *priv)
{
+ if (!priv)
+ return;
+
__raw_writel(mac_hi(priv->dev->enetaddr), &slave->regs->sa_hi);
__raw_writel(mac_lo(priv->dev->enetaddr), &slave->regs->sa_lo);
}
@@ -568,9 +571,17 @@ static void cpsw_set_slave_mac(struct cpsw_slave *slave,
static void cpsw_slave_update_link(struct cpsw_slave *slave,
struct cpsw_priv *priv, int *link)
{
- struct phy_device *phy = priv->phydev;
+ struct phy_device *phy;
u32 mac_control = 0;

+ if (!priv)
+ return;
+
+ phy = priv->phydev;
+
+ if (!phy)
+ return;
+
phy_startup(phy);
*link = phy->link;

@@ -604,8 +615,12 @@ static int cpsw_update_link(struct cpsw_priv *priv)
int link = 0;
struct cpsw_slave *slave;

+ if (!priv)
+ return -1;
+
for_each_slave(slave, priv)
cpsw_slave_update_link(slave, priv, &link);
+
priv->mdio_link = readl(&mdio_regs->link);
return link;
}
@@ -614,6 +629,9 @@ static int cpsw_check_link(struct cpsw_priv *priv)
{
u32 link = 0;

+ if (!priv)
+ return -1;
+
link = __raw_readl(&mdio_regs->link) & priv->phy_mask;
if ((link) && (link == priv->mdio_link))
return 1;
@@ -623,6 +641,9 @@ static int cpsw_check_link(struct cpsw_priv *priv)

static inline u32 cpsw_get_slave_port(struct cpsw_priv *priv, u32 slave_num)
{
+ if (!priv)
+ return -1;
+
if (priv->host_port == 0)
return slave_num + 1;
else
@@ -947,6 +968,9 @@ static int cpsw_phy_init(struct eth_device *dev, struct cpsw_slave *slave)
dev,
slave->data->phy_if);

+ if (!phydev)
+ return -1;
+
phydev->supported &= supported;
phydev->advertising = phydev->supported;

--
1.7.11.7