RE: [Intel-wired-lan] [PATCH net v2] e1000: check return value of e1000_read_eeprom

[Loktionov, Aleksandr]

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@xxxxxxxxxx> On Behalf
> Of Agalakov Daniil
> Sent: Wednesday, March 25, 2026 4:02 PM
> To: Nguyen, Anthony L <anthony.l.nguyen@xxxxxxxxx>
> Cc: Agalakov Daniil <ade@xxxxxxxxx>; Kitszel, Przemyslaw
> <przemyslaw.kitszel@xxxxxxxxx>; Andrew Lunn <andrew+netdev@xxxxxxx>;
> David S. Miller <davem@xxxxxxxxxxxxx>; Eric Dumazet
> <edumazet@xxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>; Paolo Abeni
> <pabeni@xxxxxxxxxx>; intel-wired-lan@xxxxxxxxxxxxxxxx;
> netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; lvc-
> project@xxxxxxxxxxxxxxxx; Daniil Iskhakov <dish@xxxxxxxxx>; Roman
> Razov <rrv@xxxxxxxxx>
> Subject: [Intel-wired-lan] [PATCH net v2] e1000: check return value of
> e1000_read_eeprom
> 
> [Why]
> e1000_set_eeprom() performs a read-modify-write operation when the
> write range is not word-aligned. This requires reading the first and
> last words of the range from the EEPROM to preserve the unmodified
> bytes.
> 
> However, the code does not check the return value of
> e1000_read_eeprom().
> If the read fails, the operation continues using uninitialized data
> from eeprom_buff. This results in corrupted data being written back to
> the EEPROM for the boundary words.
> 
> Add the missing error checks and abort the operation if reading fails.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Co-developed-by: Iskhakov Daniil <dish@xxxxxxxxx>
> Signed-off-by: Iskhakov Daniil <dish@xxxxxxxxx>
> Signed-off-by: Agalakov Daniil <ade@xxxxxxxxx>
> ---
> v2:
>  - Split from original series.
>  - Updated the error checking logic to be consistent with the
>    implementation in the e1000e driver.
> 
>  drivers/net/ethernet/intel/e1000/e1000_ethtool.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/net/ethernet/intel/e1000/e1000_ethtool.c
> b/drivers/net/ethernet/intel/e1000/e1000_ethtool.c
> index ab232b3fbbd0..a9c56505adcb 100644
> --- a/drivers/net/ethernet/intel/e1000/e1000_ethtool.c
> +++ b/drivers/net/ethernet/intel/e1000/e1000_ethtool.c
> @@ -506,6 +506,10 @@ static int e1000_set_eeprom(struct net_device
> *netdev,
>  					    &eeprom_buff[last_word -
> first_word]);
>  	}
> 
> +	if (ret_val)
> +		goto out;
> +
> + 
Extra blank line.
Otherwise looks good for me

Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@xxxxxxxxx>

>  	/* Device's eeprom is always little-endian, word addressable */
>  	for (i = 0; i < last_word - first_word + 1; i++)
>  		le16_to_cpus(&eeprom_buff[i]);
> @@ -522,6 +526,7 @@ static int e1000_set_eeprom(struct net_device
> *netdev,
>  	if ((ret_val == 0) && (first_word <= EEPROM_CHECKSUM_REG))
>  		e1000_update_eeprom_checksum(hw);
> 
> +out:
>  	kfree(eeprom_buff);
>  	return ret_val;
>  }
> --
> 2.51.0