[[PATCH iproute2/net-next v2] 4/4] tc: flower: make use of flower_port_attr_type() safe and silent
From: Simon Horman <hidden>
Date: 2016-12-02 08:45:40
Subsystem:
the rest · Maintainer:
Linus Torvalds
Make use of flower_port_attr_type() safe:
* flower_port_attr_type() may return a valid index into tb[] or -1.
Only access tb[] in the case of the former.
* Do not access null entries in tb[]
Also make usage silent - it is valid for ip_proto to be invalid,
for example if it is not specified as part of the filter.
Fixes: a1fb0d484237 ("tc: flower: Support matching on SCTP ports")
Signed-off-by: Simon Horman <redacted>
---
tc/f_flower.c | 24 +++++++++++++-----------
1 file changed, 13 insertions(+), 11 deletions(-)
diff --git a/tc/f_flower.c b/tc/f_flower.c
index d86ccdc3d3f0..615e8f27bed2 100644
--- a/tc/f_flower.c
+++ b/tc/f_flower.c@@ -162,19 +162,17 @@ static int flower_parse_ip_addr(char *str, __be16 eth_type, static int flower_port_attr_type(__u8 ip_proto, bool is_src) { - if (ip_proto == IPPROTO_TCP) { + if (ip_proto == IPPROTO_TCP) return is_src ? TCA_FLOWER_KEY_TCP_SRC : TCA_FLOWER_KEY_TCP_DST; - } else if (ip_proto == IPPROTO_UDP) { + else if (ip_proto == IPPROTO_UDP) return is_src ? TCA_FLOWER_KEY_UDP_SRC : TCA_FLOWER_KEY_UDP_DST; - } else if (ip_proto == IPPROTO_SCTP) { + else if (ip_proto == IPPROTO_SCTP) return is_src ? TCA_FLOWER_KEY_SCTP_SRC : TCA_FLOWER_KEY_SCTP_DST; - } else { - fprintf(stderr, "Illegal \"ip_proto\" for port\n"); + else return -1; - } } static int flower_parse_port(char *str, __u8 ip_proto, bool is_src,
@@ -511,7 +509,8 @@ static void flower_print_ip_addr(FILE *f, char *name, __be16 eth_type, static void flower_print_port(FILE *f, char *name, struct rtattr *attr) { - fprintf(f, "\n %s %d", name, ntohs(rta_getattr_u16(attr))); + if (attr) + fprintf(f, "\n %s %d", name, ntohs(rta_getattr_u16(attr))); } static int flower_print_opt(struct filter_util *qu, FILE *f,
@@ -520,6 +519,7 @@ static int flower_print_opt(struct filter_util *qu, FILE *f, struct rtattr *tb[TCA_FLOWER_MAX + 1]; __be16 eth_type = 0; __u8 ip_proto = 0xff; + int nl_type; if (!opt) return 0;
@@ -574,10 +574,12 @@ static int flower_print_opt(struct filter_util *qu, FILE *f, tb[TCA_FLOWER_KEY_IPV6_SRC], tb[TCA_FLOWER_KEY_IPV6_SRC_MASK]); - flower_print_port(f, "dst_port", - tb[flower_port_attr_type(ip_proto, false)]); - flower_print_port(f, "src_port", - tb[flower_port_attr_type(ip_proto, true)]); + nl_type = flower_port_attr_type(ip_proto, false); + if (nl_type >= 0) + flower_print_port(f, "dst_port", tb[nl_type]); + nl_type = flower_port_attr_type(ip_proto, true); + if (nl_type >= 0) + flower_print_port(f, "src_port", tb[nl_type]); if (tb[TCA_FLOWER_FLAGS]) { __u32 flags = rta_getattr_u32(tb[TCA_FLOWER_FLAGS]);
--
2.7.0.rc3.207.g0ac5344