tc: flower: make use of flower_port_attr_type() safe and silent

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: a1fb0d4842 ("tc: flower: Support matching on SCTP ports")
Signed-off-by: Simon Horman <simon.horman@netronome.com>
This commit is contained in:
Simon Horman 2016-12-03 09:52:40 +01:00 committed by Stephen Hemminger
parent 61dff9ac10
commit 6bd5b80cdc
1 changed files with 13 additions and 11 deletions

View File

@ -168,19 +168,17 @@ 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,
@ -561,7 +559,8 @@ 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, rta_getattr_be16(attr));
if (attr)
fprintf(f, "\n %s %d", name, rta_getattr_be16(attr));
}
static void flower_print_key_id(FILE *f, const char *name,
@ -577,6 +576,7 @@ 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;
@ -631,10 +631,12 @@ 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]);
flower_print_ip_addr(f, "enc_dst_ip",
tb[TCA_FLOWER_KEY_ENC_IPV4_DST_MASK] ?