That USO works for 64-bit systems is just pure luck. Currently, the
computation of the UDP segmentation header is performed using sizeof()
a pointer instead of the sizeof() the UDP header that the pointer
points to. Since the UDP header happens to be 8 bytes long and a
pointer is 8 bytes long on a 64-bit system, this works on all those
systems. But no such luck for anyone using a 32-bit system as 8 bytes
!= 4 bytes. So fix this by using sizeof() the UDP header that the
pointer points to instead.
This was found by an LLM while implementing something else that used USO.
Fixes: a54e3b8cffd6 ("Support UDP segmentation offload")
Signed-off-by: Magnus Karlsson <[email protected]>
---
drivers/net/ethernet/intel/ice/ice_txrx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c
b/drivers/net/ethernet/intel/ice/ice_txrx.c
index a2c7c4962882..d9ea812c5c4e 100644
--- a/drivers/net/ethernet/intel/ice/ice_txrx.c
+++ b/drivers/net/ethernet/intel/ice/ice_txrx.c
@@ -1925,7 +1925,7 @@ int ice_tso(struct ice_tx_buf *first, struct
ice_tx_offload_params *off)
csum_replace_by_diff(&l4.udp->check,
(__force __wsum)htonl(paylen));
/* compute length of UDP segmentation header */
- off->header_len = (u8)sizeof(l4.udp) + l4_start;
+ off->header_len = sizeof(*l4.udp) + l4_start;
} else {
csum_replace_by_diff(&l4.tcp->check,
(__force __wsum)htonl(paylen));
--
2.38.1
