diff options
| author | Guillaume Nault | 2022-02-04 14:58:14 +0100 |
|---|---|---|
| committer | Jakub Kicinski | 2022-02-07 20:12:46 -0800 |
| commit | 563f8e97e054451d167327336a53b7381517a998 (patch) | |
| tree | a3dd5f35304c41a1be2d3be1fbdfc7bf3622d3c1 /net/ipv4/fib_rules.c | |
| parent | a410a0cf98854a698a519bfbeb604145da384c0e (diff) | |
ipv4: Stop taking ECN bits into account in fib4-rules
Use the new dscp_t type to replace the tos field of struct fib4_rule,
so that fib4-rules consistently ignore ECN bits.
Before this patch, fib4-rules did accept rules with the high order ECN
bit set (but not the low order one). Also, it relied on its callers
masking the ECN bits of ->flowi4_tos to prevent those from influencing
the result. This was brittle and a few call paths still do the lookup
without masking the ECN bits first.
After this patch fib4-rules only compare the DSCP bits. ECN can't
influence the result anymore, even if the caller didn't mask these
bits. Also, fib4-rules now must have both ECN bits cleared or they will
be rejected.
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Acked-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv4/fib_rules.c')
| -rw-r--r-- | net/ipv4/fib_rules.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c index e0b6c8b6de57..117c48571cf0 100644 --- a/net/ipv4/fib_rules.c +++ b/net/ipv4/fib_rules.c @@ -23,6 +23,7 @@ #include <linux/list.h> #include <linux/rcupdate.h> #include <linux/export.h> +#include <net/inet_dscp.h> #include <net/ip.h> #include <net/route.h> #include <net/tcp.h> @@ -35,7 +36,7 @@ struct fib4_rule { struct fib_rule common; u8 dst_len; u8 src_len; - u8 tos; + dscp_t dscp; __be32 src; __be32 srcmask; __be32 dst; @@ -49,7 +50,7 @@ static bool fib4_rule_matchall(const struct fib_rule *rule) { struct fib4_rule *r = container_of(rule, struct fib4_rule, common); - if (r->dst_len || r->src_len || r->tos) + if (r->dst_len || r->src_len || r->dscp) return false; return fib_rule_matchall(rule); } @@ -185,7 +186,7 @@ INDIRECT_CALLABLE_SCOPE int fib4_rule_match(struct fib_rule *rule, ((daddr ^ r->dst) & r->dstmask)) return 0; - if (r->tos && (r->tos != fl4->flowi4_tos)) + if (r->dscp && r->dscp != inet_dsfield_to_dscp(fl4->flowi4_tos)) return 0; if (rule->ip_proto && (rule->ip_proto != fl4->flowi4_proto)) @@ -225,10 +226,12 @@ static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb, int err = -EINVAL; struct fib4_rule *rule4 = (struct fib4_rule *) rule; - if (frh->tos & ~IPTOS_TOS_MASK) { - NL_SET_ERR_MSG(extack, "Invalid tos"); + if (!inet_validate_dscp(frh->tos)) { + NL_SET_ERR_MSG(extack, + "Invalid dsfield (tos): ECN bits must be 0"); goto errout; } + rule4->dscp = inet_dsfield_to_dscp(frh->tos); /* split local/main if they are not already split */ err = fib_unmerge(net); @@ -270,7 +273,6 @@ static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb, rule4->srcmask = inet_make_mask(rule4->src_len); rule4->dst_len = frh->dst_len; rule4->dstmask = inet_make_mask(rule4->dst_len); - rule4->tos = frh->tos; net->ipv4.fib_has_custom_rules = true; @@ -313,7 +315,7 @@ static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh, if (frh->dst_len && (rule4->dst_len != frh->dst_len)) return 0; - if (frh->tos && (rule4->tos != frh->tos)) + if (frh->tos && inet_dscp_to_dsfield(rule4->dscp) != frh->tos) return 0; #ifdef CONFIG_IP_ROUTE_CLASSID @@ -337,7 +339,7 @@ static int fib4_rule_fill(struct fib_rule *rule, struct sk_buff *skb, frh->dst_len = rule4->dst_len; frh->src_len = rule4->src_len; - frh->tos = rule4->tos; + frh->tos = inet_dscp_to_dsfield(rule4->dscp); if ((rule4->dst_len && nla_put_in_addr(skb, FRA_DST, rule4->dst)) || |