[PATCH] net: ethtool: clear heap allocations for ethtool function

From: Austin Kim
Date: Tue Jun 08 2021 - 22:34:42 EST


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>
---
net/ethtool/ioctl.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 3fa7a394eabf..baa5d10043cb 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -1421,7 +1421,7 @@ 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;

@@ -1486,7 +1486,7 @@ 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;

@@ -1765,7 +1765,7 @@ 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;

@@ -2293,7 +2293,7 @@ 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);
@@ -2485,7 +2485,7 @@ 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;
if (phy_drv_tunable) {
--
2.20.1