From patchwork Thu Nov 10 10:06:58 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [RESUBMITTED, net-next, 1/2] IPv6 - support for NLM_F_* flags at IPv6 routing requests Date: Thu, 10 Nov 2011 00:06:58 -0000 From: Matti Vaittinen X-Patchwork-Id: 124834 Message-Id: <1320919619.17667.0.camel@hakki> To: ext David Miller Cc: netdev@vger.kernel.org The support for NLM_F_* flags at IPv6 routing requests. If NLM_F_CREATE flag is not defined for RTM_NEWROUTE request, warning is printed, but no error is returned. Instead new route is added. Exception is when NLM_F_REPLACE flag is given without NLM_F_CREATE, and no matching route is found. In this case it should be safe to assume that the request issuer is familiar with NLM_F_* flags, and does really not want route to be created. Specifying NLM_F_REPLACE flag will now make the kernel to search for matching route, and replace it with new one. If no route is found and NLM_F_CREATE is specified as well, then new route is created. Also, specifying NLM_F_EXCL will yield returning of error if matching route is found. Patch created against linux-3.2-rc1 Signed-off-by: Matti Vaittinen --- diff -uNr Linux-3.2-rc1.orig/net/ipv6/route.c Linux-3.2-rc1.new/net/ipv6/route.c --- Linux-3.2-rc1.orig/net/ipv6/route.c 2011-11-10 08:44:18.000000000 +0200 +++ Linux-3.2-rc1.new/net/ipv6/route.c 2011-11-10 08:46:15.000000000 +0200 @@ -1230,9 +1230,18 @@ if (cfg->fc_metric == 0) cfg->fc_metric = IP6_RT_PRIO_USER; - table = fib6_new_table(net, cfg->fc_table); + err = -ENOBUFS; + if (NULL != cfg->fc_nlinfo.nlh && + !(cfg->fc_nlinfo.nlh->nlmsg_flags&NLM_F_CREATE)) { + table = fib6_get_table(net, cfg->fc_table); + if (table == NULL) { + printk(KERN_WARNING "NLM_F_CREATE should be specified when creating new rt\n"); + table = fib6_new_table(net, cfg->fc_table); + } + } else { + table = fib6_new_table(net, cfg->fc_table); + } if (table == NULL) { - err = -ENOBUFS; goto out; }