[IPROUTE2] Routing attribute alignment fix

[Thomas Graf <tgraf@xxxxxxx>]

In case someone experiences dsmark qdisc not working correctly with
the latest iproute2 release, here's patch which fixes the problem
(and possibly other problem as well). The alignment of nlmsg_len is
calculated wrong leading to wrong rta_len calculations for nested TLVs
when the data length of the last TLV added to the nested TLV is not
aligned to RTA_ALIGNTO already.

bk tree with this fix and support for multipath algorithm selection
can be found here: bk://kernel.bkbits.net/tgraf/iproute2-tgr

# This is a BitKeeper generated diff -Nru style patch.
#
# ChangeSet
#   2005/03/20 17:19:39+01:00 tgraf@xxxxxxx 
#   Fix netlink message alignment when the last routing attribute added
#   has a data length not aligned to RTA_ALIGNTO.
# 
# lib/libnetlink.c
#   2005/03/20 17:19:38+01:00 tgraf@xxxxxxx +4 -4
#   Fix netlink message alignment when the last routing attribute added
#   has a data length not aligned to RTA_ALIGNTO.
# 
diff -Nru a/lib/libnetlink.c b/lib/libnetlink.c
--- a/lib/libnetlink.c  2005-03-21 19:12:49 +01:00
+++ b/lib/libnetlink.c  2005-03-21 19:12:49 +01:00
@@ -491,7 +491,7 @@
        int len = RTA_LENGTH(alen);
        struct rtattr *rta;
 
-       if (NLMSG_ALIGN(n->nlmsg_len) + len > maxlen) {
+       if (NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len) > maxlen) {
                fprintf(stderr, "addattr_l ERROR: message exceeded bound of 
%d\n",maxlen);
                return -1;
        }
@@ -499,7 +499,7 @@
        rta->rta_type = type;
        rta->rta_len = len;
        memcpy(RTA_DATA(rta), data, alen);
-       n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len;
+       n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len);
        return 0;
 }
 
@@ -539,7 +539,7 @@
        struct rtattr *subrta;
        int len = RTA_LENGTH(alen);
 
-       if (RTA_ALIGN(rta->rta_len) + len > maxlen) {
+       if (RTA_ALIGN(rta->rta_len) + RTA_ALIGN(len) > maxlen) {
                fprintf(stderr,"rta_addattr_l: Error! max allowed bound %d 
exceeded\n",maxlen);
                return -1;
        }
@@ -547,7 +547,7 @@
        subrta->rta_type = type;
        subrta->rta_len = len;
        memcpy(RTA_DATA(subrta), data, alen);
-       rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len;
+       rta->rta_len = NLMSG_ALIGN(rta->rta_len) + RTA_ALIGN(len);
        return 0;
 }