[PATCH 4.19 093/109] net: ethtool: clear heap allocations for ethtool function

From: Sasha Levin
Date: Mon Jun 28 2021 - 11:00:49 EST


From: Austin Kim <austindh.kim@xxxxxxxxx>

[ Upstream commit 80ec82e3d2c1fab42eeb730aaa7985494a963d3f ]

Several ethtool functions leave heap uncleared (potentially) by
drivers. This will leave the unused portion of heap unchanged and
might copy the full contents back to userspace.

Signed-off-by: Austin Kim <austindh.kim@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/core/ethtool.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 83028017c26d..4db9512feba8 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -1594,7 +1594,7 @@ static int ethtool_get_any_eeprom(struct net_device *dev, void __user *useraddr,
if (eeprom.offset + eeprom.len > total_len)
return -EINVAL;

- data = kmalloc(PAGE_SIZE, GFP_USER);
+ data = kzalloc(PAGE_SIZE, GFP_USER);
if (!data)
return -ENOMEM;

@@ -1659,7 +1659,7 @@ static int ethtool_set_eeprom(struct net_device *dev, void __user *useraddr)
if (eeprom.offset + eeprom.len > ops->get_eeprom_len(dev))
return -EINVAL;

- data = kmalloc(PAGE_SIZE, GFP_USER);
+ data = kzalloc(PAGE_SIZE, GFP_USER);
if (!data)
return -ENOMEM;

@@ -1840,7 +1840,7 @@ static int ethtool_self_test(struct net_device *dev, char __user *useraddr)
return -EFAULT;

test.len = test_len;
- data = kmalloc_array(test_len, sizeof(u64), GFP_USER);
+ data = kcalloc(test_len, sizeof(u64), GFP_USER);
if (!data)
return -ENOMEM;

@@ -2372,7 +2372,7 @@ static int ethtool_get_tunable(struct net_device *dev, void __user *useraddr)
ret = ethtool_tunable_valid(&tuna);
if (ret)
return ret;
- data = kmalloc(tuna.len, GFP_USER);
+ data = kzalloc(tuna.len, GFP_USER);
if (!data)
return -ENOMEM;
ret = ops->get_tunable(dev, &tuna, data);
@@ -2552,7 +2552,7 @@ static int get_phy_tunable(struct net_device *dev, void __user *useraddr)
ret = ethtool_phy_tunable_valid(&tuna);
if (ret)
return ret;
- data = kmalloc(tuna.len, GFP_USER);
+ data = kzalloc(tuna.len, GFP_USER);
if (!data)
return -ENOMEM;
mutex_lock(&phydev->lock);
--
2.30.2