@@ -17,6 +17,7 @@
#include <linux/rcupdate.h>
#include <net/fib_notifier.h>
#include <net/fib_rules.h>
+#include <net/inet_dscp.h>
#include <net/inetpeer.h>
#include <linux/percpu.h>
#include <linux/notifier.h>
@@ -24,7 +25,7 @@
struct fib_config {
u8 fc_dst_len;
- u8 fc_tos;
+ dscp_t fc_dscp;
u8 fc_protocol;
u8 fc_scope;
u8 fc_type;
@@ -32,6 +32,7 @@
#include <linux/list.h>
#include <linux/slab.h>
+#include <net/inet_dscp.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <net/route.h>
@@ -735,8 +736,15 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
memset(cfg, 0, sizeof(*cfg));
rtm = nlmsg_data(nlh);
+
+ if (!inet_validate_dscp(rtm->rtm_tos)) {
+ NL_SET_ERR_MSG(extack, "Invalid dsfield (tos): ECN bits must be 0");
+ err = -EINVAL;
+ goto errout;
+ }
+ cfg->fc_dscp = inet_dsfield_to_dscp(rtm->rtm_tos);
+
cfg->fc_dst_len = rtm->rtm_dst_len;
- cfg->fc_tos = rtm->rtm_tos;
cfg->fc_table = rtm->rtm_table;
cfg->fc_protocol = rtm->rtm_protocol;
cfg->fc_scope = rtm->rtm_scope;
@@ -61,6 +61,7 @@
#include <linux/vmalloc.h>
#include <linux/notifier.h>
#include <net/net_namespace.h>
+#include <net/inet_dscp.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <net/route.h>
@@ -1210,9 +1211,9 @@ int fib_table_insert(struct net *net, struct fib_table *tb,
struct fib_info *fi;
u8 plen = cfg->fc_dst_len;
u8 slen = KEYLENGTH - plen;
- u8 tos = cfg->fc_tos;
u32 key;
int err;
+ u8 tos;
key = ntohl(cfg->fc_dst);
@@ -1227,6 +1228,7 @@ int fib_table_insert(struct net *net, struct fib_table *tb,
goto err;
}
+ tos = inet_dscp_to_dsfield(cfg->fc_dscp);
l = fib_find_node(t, &tp, key);
fa = l ? fib_find_alias(&l->leaf, slen, tos, fi->fib_priority,
tb->tb_id, false) : NULL;
@@ -1703,8 +1705,8 @@ int fib_table_delete(struct net *net, struct fib_table *tb,
struct key_vector *l, *tp;
u8 plen = cfg->fc_dst_len;
u8 slen = KEYLENGTH - plen;
- u8 tos = cfg->fc_tos;
u32 key;
+ u8 tos;
key = ntohl(cfg->fc_dst);
@@ -1715,6 +1717,7 @@ int fib_table_delete(struct net *net, struct fib_table *tb,
if (!l)
return -ESRCH;
+ tos = inet_dscp_to_dsfield(cfg->fc_dscp);
fa = fib_find_alias(&l->leaf, slen, tos, 0, tb->tb_id, false);
if (!fa)
return -ESRCH;
Use the new dscp_t type to replace the fc_tos field of fib_config, to ensure IPv4 routes aren't influenced by ECN bits when configured with non-zero rtm_tos. Before this patch, IPv4 routes specifying an rtm_tos with some of the ECN bits set were accepted. However they wouldn't work (never match) as IPv4 normally clears the ECN bits with IPTOS_RT_MASK before doing a FIB lookup (although a few buggy code paths don't). After this patch, IPv4 routes specifying an rtm_tos with any ECN bit set is rejected. Note, IPv6 routes ignore rtm_tos altogether: any rtm_tos is accepted, but treated as if it were 0. Signed-off-by: Guillaume Nault <gnault@redhat.com> --- include/net/ip_fib.h | 3 ++- net/ipv4/fib_frontend.c | 10 +++++++++- net/ipv4/fib_trie.c | 7 +++++-- 3 files changed, 16 insertions(+), 4 deletions(-)