[PATCH 5.10.y] e1000e: fix EEPROM length types for overflow checks

Eliav Farber posted 1 patch 4 hours ago
drivers/net/ethernet/intel/e1000e/ethtool.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
[PATCH 5.10.y] e1000e: fix EEPROM length types for overflow checks
Posted by Eliav Farber 4 hours ago
Fix a compilation failure when warnings are treated as errors:

drivers/net/ethernet/intel/e1000e/ethtool.c: In function ‘e1000_set_eeprom’:
./include/linux/overflow.h:71:15: error: comparison of distinct pointer types lacks a cast [-Werror]
   71 |  (void) (&__a == __d);   \
      |               ^~
drivers/net/ethernet/intel/e1000e/ethtool.c:582:6: note: in expansion of macro ‘check_add_overflow’
  582 |  if (check_add_overflow(eeprom->offset, eeprom->len, &total_len) ||
      |      ^~~~~~~~~~~~~~~~~~

To fix this, change total_len and max_len from size_t to u32 in
e1000_set_eeprom().
The check_add_overflow() helper requires that the first two operands
and the pointer to the result (third operand) all have the same type.
On 64-bit builds, using size_t caused a mismatch with the u32 fields
eeprom->offset and eeprom->len, leading to type check failures.

Fixes: ce8829d3d44b ("e1000e: fix heap overflow in e1000_set_eeprom")
Signed-off-by: Eliav Farber <farbere@amazon.com>
---
 drivers/net/ethernet/intel/e1000e/ethtool.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/e1000e/ethtool.c b/drivers/net/ethernet/intel/e1000e/ethtool.c
index 4aca854783e2..584378291f3f 100644
--- a/drivers/net/ethernet/intel/e1000e/ethtool.c
+++ b/drivers/net/ethernet/intel/e1000e/ethtool.c
@@ -559,7 +559,7 @@ static int e1000_set_eeprom(struct net_device *netdev,
 {
 	struct e1000_adapter *adapter = netdev_priv(netdev);
 	struct e1000_hw *hw = &adapter->hw;
-	size_t total_len, max_len;
+	u32 total_len, max_len;
 	u16 *eeprom_buff;
 	int ret_val = 0;
 	int first_word;
-- 
2.47.3