5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Simon Horman horms@kernel.org
[ Upstream commit e7e5ae71831c44d58627a991e603845a2fed2cab ]
As it's name suggests, parse_eeprom() parses EEPROM data.
This is done by reading data, 16 bits at a time as follows:
for (i = 0; i < 128; i++) ((__le16 *) sromdata)[i] = cpu_to_le16(read_eeprom(np, i));
sromdata is at the same memory location as psrom. And the type of psrom is a pointer to struct t_SROM.
As can be seen in the loop above, data is stored in sromdata, and thus psrom, as 16-bit little-endian values.
However, the integer fields of t_SROM are host byte order integers. And in the case of led_mode this leads to a little endian value being incorrectly treated as host byte order.
Looking at rio_set_led_mode, this does appear to be a bug as that code masks led_mode with 0x1, 0x2 and 0x8. Logic that would be effected by a reversed byte order.
This problem would only manifest on big endian hosts.
Found by inspection while investigating a sparse warning regarding the crc field of t_SROM.
I believe that warning is a false positive. And although I plan to send a follow-up to use little-endian types for other the integer fields of PSROM_t I do not believe that will involve any bug fixes.
Compile tested only.
Fixes: c3f45d322cbd ("dl2k: Add support for IP1000A-based cards") Signed-off-by: Simon Horman horms@kernel.org Link: https://patch.msgid.link/20250425-dlink-led-mode-v1-1-6bae3c36e736@kernel.or... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/dlink/dl2k.c | 2 +- drivers/net/ethernet/dlink/dl2k.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/dlink/dl2k.c b/drivers/net/ethernet/dlink/dl2k.c index 55e720d2ea0c7..eb23157641343 100644 --- a/drivers/net/ethernet/dlink/dl2k.c +++ b/drivers/net/ethernet/dlink/dl2k.c @@ -358,7 +358,7 @@ parse_eeprom (struct net_device *dev) dev->dev_addr[i] = psrom->mac_addr[i];
if (np->chip_id == CHIP_IP1000A) { - np->led_mode = psrom->led_mode; + np->led_mode = le16_to_cpu(psrom->led_mode); return 0; }
diff --git a/drivers/net/ethernet/dlink/dl2k.h b/drivers/net/ethernet/dlink/dl2k.h index 195dc6cfd8955..0e33e2eaae960 100644 --- a/drivers/net/ethernet/dlink/dl2k.h +++ b/drivers/net/ethernet/dlink/dl2k.h @@ -335,7 +335,7 @@ typedef struct t_SROM { u16 sub_system_id; /* 0x06 */ u16 pci_base_1; /* 0x08 (IP1000A only) */ u16 pci_base_2; /* 0x0a (IP1000A only) */ - u16 led_mode; /* 0x0c (IP1000A only) */ + __le16 led_mode; /* 0x0c (IP1000A only) */ u16 reserved1[9]; /* 0x0e-0x1f */ u8 mac_addr[6]; /* 0x20-0x25 */ u8 reserved2[10]; /* 0x26-0x2f */