From: Petr Oros poros@redhat.com
[ Upstream commit 84cba1840e68430325ac133a11be06bfb2f7acd8 ]
ice_get_module_eeprom() is broken since commit e9c9692c8a81 ("ice: Reimplement module reads used by ethtool") In this refactor, ice_get_module_eeprom() reads the eeprom in blocks of size 8. But the condition that should protect the buffer overflow ignores the last block. The last block always contains zeros.
Bug uncovered by ethtool upstream commit 9538f384b535 ("netlink: eeprom: Defer page requests to individual parsers") After this commit, ethtool reads a block with length = 1; to read the SFF-8024 identifier value.
unpatched driver: $ ethtool -m enp65s0f0np0 offset 0x90 length 8 Offset Values ------ ------ 0x0090: 00 00 00 00 00 00 00 00 $ ethtool -m enp65s0f0np0 offset 0x90 length 12 Offset Values ------ ------ 0x0090: 00 00 01 a0 4d 65 6c 6c 00 00 00 00 $
$ ethtool -m enp65s0f0np0 Offset Values ------ ------ 0x0000: 11 06 06 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0060: 00 00 00 00 00 00 00 00 00 00 00 00 00 01 08 00 0x0070: 00 10 00 00 00 00 00 00 00 00 00 00 00 00 00 00
patched driver: $ ethtool -m enp65s0f0np0 offset 0x90 length 8 Offset Values ------ ------ 0x0090: 00 00 01 a0 4d 65 6c 6c $ ethtool -m enp65s0f0np0 offset 0x90 length 12 Offset Values ------ ------ 0x0090: 00 00 01 a0 4d 65 6c 6c 61 6e 6f 78 $ ethtool -m enp65s0f0np0 Identifier : 0x11 (QSFP28) Extended identifier : 0x00 Extended identifier description : 1.5W max. Power consumption Extended identifier description : No CDR in TX, No CDR in RX Extended identifier description : High Power Class (> 3.5 W) not enabled Connector : 0x23 (No separable connector) Transceiver codes : 0x88 0x00 0x00 0x00 0x00 0x00 0x00 0x00 Transceiver type : 40G Ethernet: 40G Base-CR4 Transceiver type : 25G Ethernet: 25G Base-CR CA-N Encoding : 0x05 (64B/66B) BR, Nominal : 25500Mbps Rate identifier : 0x00 Length (SMF,km) : 0km Length (OM3 50um) : 0m Length (OM2 50um) : 0m Length (OM1 62.5um) : 0m Length (Copper or Active cable) : 1m Transmitter technology : 0xa0 (Copper cable unequalized) Attenuation at 2.5GHz : 4db Attenuation at 5.0GHz : 5db Attenuation at 7.0GHz : 7db Attenuation at 12.9GHz : 10db ........ ....
Fixes: e9c9692c8a81 ("ice: Reimplement module reads used by ethtool") Signed-off-by: Petr Oros poros@redhat.com Reviewed-by: Jesse Brandeburg jesse.brandeburg@intel.com Tested-by: Jesse Brandeburg jesse.brandeburg@intel.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/ice/ice_ethtool.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c index a359f1610fc19..8ca61610cec23 100644 --- a/drivers/net/ethernet/intel/ice/ice_ethtool.c +++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c @@ -4314,6 +4314,8 @@ ice_get_module_eeprom(struct net_device *netdev, * SFP modules only ever use page 0. */ if (page == 0 || !(data[0x2] & 0x4)) { + u32 copy_len; + /* If i2c bus is busy due to slow page change or * link management access, call can fail. This is normal. * So we retry this a few times. @@ -4337,8 +4339,8 @@ ice_get_module_eeprom(struct net_device *netdev, }
/* Make sure we have enough room for the new block */ - if ((i + SFF_READ_BLOCK_SIZE) < ee->len) - memcpy(data + i, value, SFF_READ_BLOCK_SIZE); + copy_len = min_t(u32, SFF_READ_BLOCK_SIZE, ee->len - i); + memcpy(data + i, value, copy_len); } } return 0;