pimd: fix MSDP packet debug crashes

Add some safe guards to avoid crashes and alert us about programming
errors in packet build.

Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
This commit is contained in:
Rafael Zalamena 2022-12-07 11:49:26 -03:00
parent d49810329d
commit 1dd422a22b

View File

@ -83,10 +83,18 @@ static void pim_msdp_pkt_sa_dump_one(struct stream *s)
static void pim_msdp_pkt_sa_dump(struct stream *s)
{
const size_t header_length = PIM_MSDP_SA_X_SIZE - PIM_MSDP_HEADER_SIZE;
size_t payload_length;
int entry_cnt;
int i;
struct in_addr rp; /* Last RP address associated with this SA */
if (header_length > STREAM_READABLE(s)) {
zlog_err("BUG MSDP SA bad header (readable %zu expected %zu)",
STREAM_READABLE(s), header_length);
return;
}
entry_cnt = stream_getc(s);
rp.s_addr = stream_get_ipv4(s);
@ -96,6 +104,13 @@ static void pim_msdp_pkt_sa_dump(struct stream *s)
zlog_debug(" entry_cnt %d rp %s", entry_cnt, rp_str);
}
payload_length = (size_t)entry_cnt * PIM_MSDP_SA_ONE_ENTRY_SIZE;
if (payload_length > STREAM_READABLE(s)) {
zlog_err("BUG MSDP SA bad length (readable %zu expected %zu)",
STREAM_READABLE(s), payload_length);
return;
}
/* dump SAs */
for (i = 0; i < entry_cnt; ++i) {
pim_msdp_pkt_sa_dump_one(s);
@ -116,6 +131,11 @@ static void pim_msdp_pkt_dump(struct pim_msdp_peer *mp, int type, int len,
return;
}
if (len < PIM_MSDP_HEADER_SIZE) {
zlog_err("invalid MSDP header length");
return;
}
switch (type) {
case PIM_MSDP_V4_SOURCE_ACTIVE:
pim_msdp_pkt_sa_dump(s);