ip: fix crash in "ip neigh show"

parse_rtattr() was using tb[] array without initializing it.

Based on patch by Balaji Punnuru <balaji_punnuru@cable.comcast.com>

function                                             old     new   delta
parse_rtattr                                          85     107     +22
print_route                                         1630    1617     -13
print_linkinfo                                       807     794     -13
iproute_get                                          835     822     -13
print_rule                                           680     665     -15
ll_remember_index                                    263     248     -15
print_addrinfo                                      1223    1197     -26
ipaddr_list_or_flush                                1253    1223     -30
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/7 up/down: 22/-125)          Total: -103 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2018-02-08 08:42:37 +01:00
parent 237a900bc5
commit 68ae54243c
7 changed files with 28 additions and 20 deletions

View File

@ -113,7 +113,7 @@ static NOINLINE int print_linkinfo(const struct nlmsghdr *n)
if (G_filter.up && !(ifi->ifi_flags & IFF_UP))
return 0;
memset(tb, 0, sizeof(tb));
//memset(tb, 0, sizeof(tb)); - parse_rtattr does this
parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
if (tb[IFLA_IFNAME] == NULL) {
bb_error_msg("nil ifname");
@ -227,7 +227,7 @@ static int FAST_FUNC print_addrinfo(const struct sockaddr_nl *who UNUSED_PARAM,
if (G_filter.flushb && n->nlmsg_type != RTM_NEWADDR)
return 0;
memset(rta_tb, 0, sizeof(rta_tb));
//memset(rta_tb, 0, sizeof(rta_tb)); - parse_rtattr does this
parse_rtattr(rta_tb, IFA_MAX, IFA_RTA(ifa), n->nlmsg_len - NLMSG_LENGTH(sizeof(*ifa)));
if (!rta_tb[IFA_LOCAL])
@ -535,7 +535,7 @@ int FAST_FUNC ipaddr_list_or_flush(char **argv, int flush)
continue;
if (G_filter.pfx.family || G_filter.label) {
struct rtattr *tb[IFA_MAX+1];
memset(tb, 0, sizeof(tb));
//memset(tb, 0, sizeof(tb)); - parse_rtattr does this
parse_rtattr(tb, IFA_MAX, IFA_RTA(ifa), IFA_PAYLOAD(n));
if (!tb[IFA_LOCAL])
tb[IFA_LOCAL] = tb[IFA_ADDRESS];

View File

@ -110,11 +110,13 @@ static int FAST_FUNC print_neigh(const struct sockaddr_nl *who UNUSED_PARAM,
return 0;
if (G_filter.index && G_filter.index != r->ndm_ifindex)
return 0;
if (!(G_filter.state&r->ndm_state) &&
!(r->ndm_flags & NTF_PROXY) &&
(r->ndm_state || !(G_filter.state & 0x100)) &&
(r->ndm_family != AF_DECnet))
if (!(G_filter.state&r->ndm_state)
&& !(r->ndm_flags & NTF_PROXY)
&& (r->ndm_state || !(G_filter.state & 0x100))
&& (r->ndm_family != AF_DECnet)
) {
return 0;
}
parse_rtattr(tb, NDA_MAX, NDA_RTA(r), n->nlmsg_len - NLMSG_LENGTH(sizeof(*r)));

View File

@ -83,7 +83,7 @@ static int FAST_FUNC print_route(const struct sockaddr_nl *who UNUSED_PARAM,
if (len < 0)
bb_error_msg_and_die("wrong nlmsg len %d", len);
memset(tb, 0, sizeof(tb));
//memset(tb, 0, sizeof(tb)); - parse_rtattr does this
parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len);
#if HAVE_RTA_TABLE
@ -1081,7 +1081,7 @@ static int iproute_get(char **argv)
bb_error_msg_and_die("wrong len %d", len);
}
memset(tb, 0, sizeof(tb));
//memset(tb, 0, sizeof(tb)); - parse_rtattr does this
parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len);
if (tb[RTA_PREFSRC]) {

View File

@ -63,7 +63,7 @@ static int FAST_FUNC print_rule(const struct sockaddr_nl *who UNUSED_PARAM,
if (len < 0)
return -1;
memset(tb, 0, sizeof(tb));
//memset(tb, 0, sizeof(tb)); - parse_rtattr does this
parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len);
if (r->rtm_family == AF_INET)

View File

@ -401,6 +401,8 @@ int FAST_FUNC rta_addattr_l(struct rtattr *rta, int maxlen, int type, void *data
void FAST_FUNC parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len)
{
memset(tb, 0, (max + 1) * sizeof(tb[0]));
while (RTA_OK(rta, len)) {
if (rta->rta_type <= max) {
tb[rta->rta_type] = rta;

View File

@ -51,7 +51,7 @@ int FAST_FUNC ll_remember_index(const struct sockaddr_nl *who UNUSED_PARAM,
if (n->nlmsg_len < NLMSG_LENGTH(sizeof(ifi)))
return -1;
memset(tb, 0, sizeof(tb));
//memset(tb, 0, sizeof(tb)); - parse_rtattr does this
parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), IFLA_PAYLOAD(n));
if (tb[IFLA_IFNAME] == NULL)
return 0;

View File

@ -66,17 +66,21 @@ enum
/* nullifies tb on error */
#define __parse_rtattr_nested_compat(tb, max, rta, len) \
({if ((RTA_PAYLOAD(rta) >= len) && \
(RTA_PAYLOAD(rta) >= RTA_ALIGN(len) + sizeof(struct rtattr))) { \
rta = RTA_DATA(rta) + RTA_ALIGN(len); \
parse_rtattr_nested(tb, max, rta); \
} else \
memset(tb, 0, sizeof(struct rtattr *) * (max + 1)); \
})
({ \
if ((RTA_PAYLOAD(rta) >= len) \
&& (RTA_PAYLOAD(rta) >= RTA_ALIGN(len) + sizeof(struct rtattr)) \
) { \
rta = RTA_DATA(rta) + RTA_ALIGN(len); \
parse_rtattr_nested(tb, max, rta); \
} else \
memset(tb, 0, sizeof(struct rtattr *) * (max + 1)); \
})
#define parse_rtattr_nested_compat(tb, max, rta, data, len) \
({data = RTA_PAYLOAD(rta) >= len ? RTA_DATA(rta) : NULL; \
__parse_rtattr_nested_compat(tb, max, rta, len); })
({ \
data = RTA_PAYLOAD(rta) >= len ? RTA_DATA(rta) : NULL; \
__parse_rtattr_nested_compat(tb, max, rta, len); \
})
#define show_details (0) /* not implemented. Does anyone need it? */
#define use_iec (0) /* not currently documented in the upstream manpage */