From 38561437d056b11f679f9735d68ad597ba67dc84 Mon Sep 17 00:00:00 2001 From: Simon Horman Date: Fri, 19 Apr 2013 10:43:44 +0900 Subject: [PATCH] ipvs: Use network byte order for sync message size struct ip_vs_sync_mesg and ip_vs_sync_mesg_v0 are both sent across the wire and used internally to store IPVS synchronisation messages. Up until now the scheme used has been to convert the size field to network byte order before sending a message on the wire and convert it to host byte order when sending a message. This patch changes that scheme to always treat the field as being network byte order. This seems appropriate as the structure is sent across the wire. And by consistently treating the field has network byte order it is now possible to take advantage of sparse to flag any future miss-use. Acked-by: Julian Anastasov Acked-by: Hans Schillstrom Signed-off-by: Simon Horman --- net/netfilter/ipvs/ip_vs_sync.c | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c index 8e57077e5540..f6046d9af8d3 100644 --- a/net/netfilter/ipvs/ip_vs_sync.c +++ b/net/netfilter/ipvs/ip_vs_sync.c @@ -246,7 +246,7 @@ struct ip_vs_sync_thread_data { struct ip_vs_sync_mesg_v0 { __u8 nr_conns; __u8 syncid; - __u16 size; + __be16 size; /* ip_vs_sync_conn entries start here */ }; @@ -255,7 +255,7 @@ struct ip_vs_sync_mesg_v0 { struct ip_vs_sync_mesg { __u8 reserved; /* must be zero */ __u8 syncid; - __u16 size; + __be16 size; __u8 nr_conns; __s8 version; /* SYNC_PROTO_VER */ __u16 spare; @@ -335,7 +335,7 @@ ip_vs_sync_buff_create(struct netns_ipvs *ipvs) sb->mesg->reserved = 0; /* old nr_conns i.e. must be zero now */ sb->mesg->version = SYNC_PROTO_VER; sb->mesg->syncid = ipvs->master_syncid; - sb->mesg->size = sizeof(struct ip_vs_sync_mesg); + sb->mesg->size = htons(sizeof(struct ip_vs_sync_mesg)); sb->mesg->nr_conns = 0; sb->mesg->spare = 0; sb->head = (unsigned char *)sb->mesg + sizeof(struct ip_vs_sync_mesg); @@ -418,7 +418,7 @@ ip_vs_sync_buff_create_v0(struct netns_ipvs *ipvs) mesg = (struct ip_vs_sync_mesg_v0 *)sb->mesg; mesg->nr_conns = 0; mesg->syncid = ipvs->master_syncid; - mesg->size = sizeof(struct ip_vs_sync_mesg_v0); + mesg->size = htons(sizeof(struct ip_vs_sync_mesg_v0)); sb->head = (unsigned char *)mesg + sizeof(struct ip_vs_sync_mesg_v0); sb->end = (unsigned char *)mesg + ipvs->send_mesg_maxlen; sb->firstuse = jiffies; @@ -582,7 +582,7 @@ static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp, } m->nr_conns++; - m->size += len; + m->size = htons(ntohs(m->size) + len); buff->head += len; /* check if there is a space for next one */ @@ -693,7 +693,7 @@ sloop: p = buff->head; buff->head += pad + len; - m->size += pad + len; + m->size = htons(ntohs(m->size) + pad + len); /* Add ev. padding from prev. sync_conn */ while (pad--) *(p++) = 0; @@ -1175,10 +1175,8 @@ static void ip_vs_process_message(struct net *net, __u8 *buffer, IP_VS_DBG(2, "BACKUP, message header too short\n"); return; } - /* Convert size back to host byte order */ - m2->size = ntohs(m2->size); - if (buflen != m2->size) { + if (buflen != ntohs(m2->size)) { IP_VS_DBG(2, "BACKUP, bogus message size\n"); return; } @@ -1544,10 +1542,7 @@ ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg) int msize; int ret; - msize = msg->size; - - /* Put size in network byte order */ - msg->size = htons(msg->size); + msize = ntohs(msg->size); ret = ip_vs_send_async(sock, (char *)msg, msize); if (ret >= 0 || ret == -EAGAIN) -- 2.20.1