Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux

net: dl2k: Use proper conversion of dev_addr before IO to device

The driver is using iowriteXX()/ioreadXX() APIs which are LE IO
accessors simplified as

1. Convert given value _from_ CPU _to_ LE
2. Write it to the device as is

The dev_addr is a byte stream, but because the driver uses 16-bit
IO accessors, it wants to perform double conversion on BE CPUs,
but it took it wrong, as it effectivelly does two times _from_ CPU
_to_ LE. What it has to do is to consider dev_addr as an array of
LE16 and hence do _from_ LE _to_ CPU conversion, followed by implied
_from_ CPU _to_ LE in the iowrite16().

To achieve that, use get_unaligned_le16(). This will make it correct
and allows to avoid sparse warning as reported by LKP.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202312030058.hfZPTXd7-lkp@intel.com/
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231208153327.3306798-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

authored by

Andy Shevchenko and committed by
Paolo Abeni
68cbdb15 68c84289

+1 -2
+1 -2
drivers/net/ethernet/dlink/dl2k.c
··· 565 565 * too. However, it doesn't work on IP1000A so we use 16-bit access. 566 566 */ 567 567 for (i = 0; i < 3; i++) 568 - dw16(StationAddr0 + 2 * i, 569 - cpu_to_le16(((const u16 *)dev->dev_addr)[i])); 568 + dw16(StationAddr0 + 2 * i, get_unaligned_le16(&dev->dev_addr[2 * i])); 570 569 571 570 set_multicast (dev); 572 571 if (np->coalesce) {