[PATCH iwl-net] ice: allow reading the last byte of the NVM and Shadow RAM regions

ice_devlink_nvm_read() rejects a read whose end lands exactly on the
region size, so feeding back the size devlink itself reports fails:

  devlink region show pci/0000:04:00.0/nvm-flash
  pci/0000:04:00.0/nvm-flash: size 10485760 snapshot [] max 1

  devlink region read pci/0000:04:00.0/nvm-flash address 0 length 10485760
  Error: ice: Cannot read beyond the region size.

shadow-ram behaves the same. The regions are created with those sizes, so
a read ending on the size is the whole region and has to be allowed.
ice_read_flat_nvm() uses > for its own Shadow RAM check, and so does
ixgbe, which grew its region support from this code.

Fixes: 3af4b40b0f2f ("ice: implement direct read for NVM and Shadow RAM regions")
Signed-off-by: Petr Oros <[email protected]>
---
 drivers/net/ethernet/intel/ice/devlink/devlink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ice/devlink/devlink.c b/drivers/net/ethernet/intel/ice/devlink/devlink.c
index 8c2b63eef82bd5..a52b6044288975 100644
--- a/drivers/net/ethernet/intel/ice/devlink/devlink.c
+++ b/drivers/net/ethernet/intel/ice/devlink/devlink.c
@@ -1953,7 +1953,7 @@ static int ice_devlink_nvm_read(struct devlink *devlink,
 		return -EOPNOTSUPP;
 	}
 
-	if (offset + size >= nvm_size) {
+	if (offset + size > nvm_size) {
 		NL_SET_ERR_MSG_MOD(extack, "Cannot read beyond the region size");
 		return -ERANGE;
 	}
-- 
2.54.0