On Fri, Oct 23, 2026 at 04:09:57PM +0000, [email protected] wrote: > Thank you for your contribution! Sashiko AI review found 1 potential issue(s) > to consider: > - [Low] net: virtio_net: sparse __virtio16 mismatch in > virtio_net_hdr_tnl_to_skb() > -- > > commit ba7ce0ae4b2dfb77c6b110ada68faaf66de9237f > Author: Cheng Yongkang <[email protected]> > > net: virtio_net: decode tunnel csum_start as little-endian > > This commit changes virtio_net_hdr_tnl_to_skb() in include/linux/virtio_net.h > to always decode hdr->csum_start as little-endian during tunnel header offset > validation, matching the subsequent call to __virtio_net_hdr_to_skb(). > > > diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h > > index d6466f96cdd00..ddc6341747e53 100644 > > --- a/include/linux/virtio_net.h > > +++ b/include/linux/virtio_net.h > > @@ -324,7 +324,7 @@ virtio_net_hdr_tnl_to_skb(struct sk_buff *skb, > > inner_l3min = virtio_l3min(inner_isv6); > > outer_l3min = ETH_HLEN + virtio_l3min(outer_isv6); > > > > - inner_th = __virtio16_to_cpu(little_endian, hdr->csum_start); > > + inner_th = le16_to_cpu(hdr->csum_start); > > inner_nh = le16_to_cpu(vhdr->inner_nh_offset); > > outer_th = le16_to_cpu(vhdr->outer_th_offset); > > if (outer_th < outer_l3min || > > [Severity: Low] > Does passing hdr->csum_start directly to le16_to_cpu() in > virtio_net_hdr_tnl_to_skb() trigger sparse endianness warnings when building > callers such as drivers/net/virtio_net.c and drivers/net/tun.c with C=1? > > Unlike vhdr->inner_nh_offset and vhdr->outer_th_offset, which are declared as > __le16 in struct virtio_net_hdr_v1_hash_tunnel, hdr->csum_start is declared as > __virtio16 in include/uapi/linux/virtio_net.h: > > struct virtio_net_hdr { > ... > __virtio16 csum_start; /* Position to start checksumming from */ > __virtio16 csum_offset; /* Offset after that to place checksum */ > }; > > In include/linux/virtio_byteorder.h, __virtio16_to_cpu() performs the forced > cast from __virtio16 to __le16 before calling le16_to_cpu(): > > static inline u16 __virtio16_to_cpu(bool little_endian, __virtio16 val) > { > if (little_endian) > return le16_to_cpu((__force __le16)val); > else > return be16_to_cpu((__force __be16)val); > } > > Should this use __virtio16_to_cpu(true, hdr->csum_start) instead, matching the > __virtio_net_hdr_to_skb(skb, hdr, true, ...) call below and > __cpu_to_virtio16(true, hdr_len) in __virtio_net_set_tnl_hdrlen()?
Ugh. In fact it does. Should be __virtio16_to_cpu(true, hdr->csum_start) and I had exactly that in v5. Not sure at what point I picked an old version of that ( It's just a warning - functionally the same - so if v6 goes in, I'll fix it by a patch on top. > -- > Sashiko AI review ยท > https://sashiko.dev/#/patchset/[email protected]?part=1
