From 656acdfc26b0a03329db005e41d0aaf789afca29 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Wed, 28 Sep 2022 14:33:27 +1000 Subject: Avoid ugly 'end' members in netlink structures We use a number of complex structures to format messages to send to netlink. In some cases we add imaginary 'end' members not because they actually mean something on the wire, but so that we can use offsetof() on the member to determine the relevant size. Adding extra things to the structures for this is kinda nasty. We can use a different construct with offsetof and sizeof to avoid them. As a bonus this removes some cppcheck warnings about unused struct members. Signed-off-by: David Gibson Signed-off-by: Stefano Brivio --- netlink.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) (limited to 'netlink.c') diff --git a/netlink.c b/netlink.c index 6f7ada8..15ce213 100644 --- a/netlink.c +++ b/netlink.c @@ -206,7 +206,6 @@ void nl_route(int ns, unsigned int ifi, sa_family_t af, void *gw) uint32_t d; struct rtattr rta_gw; uint32_t a; - uint8_t end; } r4; } set; } req = { @@ -234,7 +233,8 @@ void nl_route(int ns, unsigned int ifi, sa_family_t af, void *gw) if (af == AF_INET6) { size_t rta_len = RTA_LENGTH(sizeof(req.set.r6.d)); - req.nlh.nlmsg_len = sizeof(req); + req.nlh.nlmsg_len = offsetof(struct req_t, set.r6) + + sizeof(req.set.r6); req.set.r6.rta_dst.rta_type = RTA_DST; req.set.r6.rta_dst.rta_len = rta_len; @@ -245,7 +245,8 @@ void nl_route(int ns, unsigned int ifi, sa_family_t af, void *gw) } else { size_t rta_len = RTA_LENGTH(sizeof(req.set.r4.d)); - req.nlh.nlmsg_len = offsetof(struct req_t, set.r4.end); + req.nlh.nlmsg_len = offsetof(struct req_t, set.r4) + + sizeof(req.set.r4); req.set.r4.rta_dst.rta_type = RTA_DST; req.set.r4.rta_dst.rta_len = rta_len; @@ -312,8 +313,6 @@ void nl_addr(int ns, unsigned int ifi, sa_family_t af, uint32_t l; struct rtattr rta_a; uint32_t a; - - uint8_t end; } a4; struct { struct rtattr rta_l; @@ -343,7 +342,8 @@ void nl_addr(int ns, unsigned int ifi, sa_family_t af, if (af == AF_INET6) { size_t rta_len = RTA_LENGTH(sizeof(req.set.a6.l)); - req.nlh.nlmsg_len = sizeof(req); + req.nlh.nlmsg_len = offsetof(struct req_t, set.a6) + + sizeof(req.set.a6); memcpy(&req.set.a6.l, addr, sizeof(req.set.a6.l)); req.set.a6.rta_l.rta_len = rta_len; @@ -354,7 +354,8 @@ void nl_addr(int ns, unsigned int ifi, sa_family_t af, } else { size_t rta_len = RTA_LENGTH(sizeof(req.set.a4.l)); - req.nlh.nlmsg_len = offsetof(struct req_t, set.a4.end); + req.nlh.nlmsg_len = offsetof(struct req_t, set.a4) + + sizeof(req.set.a4); req.set.a4.l = req.set.a4.a = *(uint32_t *)addr; req.set.a4.rta_l.rta_len = rta_len; @@ -425,7 +426,6 @@ void nl_link(int ns, unsigned int ifi, void *mac, int up, int mtu) unsigned char mac[ETH_ALEN]; struct { unsigned int mtu; - uint8_t end; } mtu; } set; } req = { @@ -457,7 +457,8 @@ void nl_link(int ns, unsigned int ifi, void *mac, int up, int mtu) } if (mtu) { - req.nlh.nlmsg_len = offsetof(struct req_t, set.mtu.end); + req.nlh.nlmsg_len = offsetof(struct req_t, set.mtu) + + sizeof(req.set.mtu); req.set.mtu.mtu = mtu; req.rta.rta_type = IFLA_MTU; req.rta.rta_len = RTA_LENGTH(sizeof(unsigned int)); -- cgit v1.2.3