Hi Marc-André,
On 02/09/2018 04:03 PM, Marc-André Lureau wrote:
> Fixes the following ASAN warnings:
>
> /home/elmarco/src/qemu/hw/net/net_tx_pkt.c:201:27: runtime error: member
> access within misaligned address 0x631000028846 for type 'struct ip_header',
> which requires 4 byte alignment
> 0x631000028846: note: pointer points here
> 01 00 00 00 45 00 01 a9 01 00 00 00 40 11 78 45 00 00 00 00 ff ff ff ff
> 00 00 00 00 00 00 00 00
> ^
> /home/elmarco/src/qemu/hw/net/net_tx_pkt.c:208:63: runtime error: member
> access within misaligned address 0x631000028846 for type 'struct ip_header',
> which requires 4 byte alignment
> 0x631000028846: note: pointer points here
> 01 00 00 00 45 00 01 a9 01 00 00 00 40 11 78 45 00 00 00 00 ff ff ff ff
> 00 00 00 00 00 00 00 00
> ^
> /home/elmarco/src/qemu/hw/net/net_tx_pkt.c:210:13: runtime error: member
> access within misaligned address 0x631000028846 for type 'struct ip_header',
> which requires 4 byte alignment
> 0x631000028846: note: pointer points here
> 01 00 00 00 45 00 01 a9 01 00 00 00 40 11 78 45 00 00 00 00 ff ff ff ff
> 00 00 00 00 00 00 00 00
>
> Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>
> ---
> include/net/eth.h | 4 +++-
> hw/net/net_tx_pkt.c | 2 +-
> 2 files changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/include/net/eth.h b/include/net/eth.h
> index 09054a506d..e6dc8a7ba0 100644
> --- a/include/net/eth.h
> +++ b/include/net/eth.h
> @@ -194,7 +194,9 @@ struct tcp_hdr {
> #define PKT_GET_IP_HDR(p) \
> ((struct ip_header *)(((uint8_t *)(p)) + eth_get_l2_hdr_length(p)))
> #define IP_HDR_GET_LEN(p) \
> - ((((struct ip_header *)(p))->ip_ver_len & 0x0F) << 2)
> + ((ldub_p(p + offsetof(struct ip_header, ip_ver_len)) & 0x0F) << 2)
I like the idea of using the ldst API and offsetof() macro,
however I think it would be cleaner to use inlined static functions.
> +#define IP_HDR_GET_P(p) \
> + (ldub_p(p + offsetof(struct ip_header, ip_p)))
> #define PKT_GET_IP_HDR_LEN(p) \
> (IP_HDR_GET_LEN(PKT_GET_IP_HDR(p)))
> #define PKT_GET_IP6_HDR(p) \
> diff --git a/hw/net/net_tx_pkt.c b/hw/net/net_tx_pkt.c
> index e29c881bc2..162f802dd7 100644
> --- a/hw/net/net_tx_pkt.c
> +++ b/hw/net/net_tx_pkt.c
> @@ -205,7 +205,7 @@ static bool net_tx_pkt_parse_headers(struct NetTxPkt *pkt)
> return false;
> }
>
> - pkt->l4proto = ((struct ip_header *) l3_hdr->iov_base)->ip_p;
> + pkt->l4proto = IP_HDR_GET_P(l3_hdr->iov_base);
>
> if (IP_HDR_GET_LEN(l3_hdr->iov_base) != sizeof(struct ip_header)) {
> /* copy optional IPv4 header data if any*/
>
