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 post@mikaelkw.online Signed-off-by: Mikael Wessel post@mikaelkw.online Cc: stable@vger.kernel.org
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++)