On 5/27/2025 1:56 AM, Mikael Wessel wrote:
The ETHTOOL_SETEEPROM ioctl copies user data into a kmalloc'ed buffer
without validating eeprom->len and eeprom->offset. A CAP_NET_ADMIN
user can overflow the heap and crash the kernel or gain code execution.
Validate length and offset before memcpy().
Fixes: bc7f75fa9788 ("[E1000E]: New pci-express e1000 driver (currently for ICH9
devices only)")
Reported-by: Mikael Wessel <[email protected]>
Signed-off-by: Mikael Wessel <[email protected]>
Cc: [email protected]
---
drivers/net/ethernet/intel/e1000e/ethtool.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/net/ethernet/intel/e1000e/ethtool.c
b/drivers/net/ethernet/intel/e1000e/ethtool.c
index 9364bc2b4eb1..98e541e39730 100644
--- a/drivers/net/ethernet/intel/e1000e/ethtool.c
+++ b/drivers/net/ethernet/intel/e1000e/ethtool.c
@@ -596,6 +596,9 @@ static int e1000_set_eeprom(struct net_device *netdev,
for (i = 0; i < last_word - first_word + 1; i++)
le16_to_cpus(&eeprom_buff[i]);
+ if (eeprom->len > max_len ||
+ eeprom->offset > max_len - eeprom->len)
+ return -EINVAL;
This is going to cause 'eeprom_buff' to leak. You should use the goto
out, however, seems like these checks can be moved up before the
allocation is done. Also, indentation looks off.
Thanks,
Tony
memcpy(ptr, bytes, eeprom->len);
for (i = 0; i < last_word - first_word + 1; i++)
