[PATCH 5.16 0385/1039] fsl/fman: Check for null pointer after calling devm_ioremap

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 18:46:27 EST


From: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>

[ Upstream commit d5a73ec96cc57cf67e51b12820fc2354e7ca46f8 ]

As the possible failure of the allocation, the devm_ioremap() may return
NULL pointer.
Take tgec_initialization() as an example.
If allocation fails, the params->base_addr will be NULL pointer and will
be assigned to tgec->regs in tgec_config().
Then it will cause the dereference of NULL pointer in set_mac_address(),
which is called by tgec_init().
Therefore, it should be better to add the sanity check after the calling
of the devm_ioremap().

Fixes: 3933961682a3 ("fsl/fman: Add FMan MAC driver")
Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/freescale/fman/mac.c | 21 ++++++++++++++++-----
1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fman/mac.c b/drivers/net/ethernet/freescale/fman/mac.c
index d9fc5c456bf3e..39ae965cd4f64 100644
--- a/drivers/net/ethernet/freescale/fman/mac.c
+++ b/drivers/net/ethernet/freescale/fman/mac.c
@@ -94,14 +94,17 @@ static void mac_exception(void *handle, enum fman_mac_exceptions ex)
__func__, ex);
}

-static void set_fman_mac_params(struct mac_device *mac_dev,
- struct fman_mac_params *params)
+static int set_fman_mac_params(struct mac_device *mac_dev,
+ struct fman_mac_params *params)
{
struct mac_priv_s *priv = mac_dev->priv;

params->base_addr = (typeof(params->base_addr))
devm_ioremap(priv->dev, mac_dev->res->start,
resource_size(mac_dev->res));
+ if (!params->base_addr)
+ return -ENOMEM;
+
memcpy(&params->addr, mac_dev->addr, sizeof(mac_dev->addr));
params->max_speed = priv->max_speed;
params->phy_if = mac_dev->phy_if;
@@ -112,6 +115,8 @@ static void set_fman_mac_params(struct mac_device *mac_dev,
params->event_cb = mac_exception;
params->dev_id = mac_dev;
params->internal_phy_node = priv->internal_phy_node;
+
+ return 0;
}

static int tgec_initialization(struct mac_device *mac_dev)
@@ -123,7 +128,9 @@ static int tgec_initialization(struct mac_device *mac_dev)

priv = mac_dev->priv;

- set_fman_mac_params(mac_dev, &params);
+ err = set_fman_mac_params(mac_dev, &params);
+ if (err)
+ goto _return;

mac_dev->fman_mac = tgec_config(&params);
if (!mac_dev->fman_mac) {
@@ -169,7 +176,9 @@ static int dtsec_initialization(struct mac_device *mac_dev)

priv = mac_dev->priv;

- set_fman_mac_params(mac_dev, &params);
+ err = set_fman_mac_params(mac_dev, &params);
+ if (err)
+ goto _return;

mac_dev->fman_mac = dtsec_config(&params);
if (!mac_dev->fman_mac) {
@@ -218,7 +227,9 @@ static int memac_initialization(struct mac_device *mac_dev)

priv = mac_dev->priv;

- set_fman_mac_params(mac_dev, &params);
+ err = set_fman_mac_params(mac_dev, &params);
+ if (err)
+ goto _return;

if (priv->max_speed == SPEED_10000)
params.phy_if = PHY_INTERFACE_MODE_XGMII;
--
2.34.1