passt: Address new clang-tidy warnings from LLVM 13.0.1

clang-tidy from LLVM 13.0.1 reports some new warnings from these
checkers:

- altera-unroll-loops, altera-id-dependent-backward-branch: ignore
  for the moment being, add a TODO item

- bugprone-easily-swappable-parameters: ignore, nothing to do about
  those

- readability-function-cognitive-complexity: ignore for the moment
  being, add a TODO item

- altera-struct-pack-align: ignore, alignment is forced in protocol
  headers

- concurrency-mt-unsafe: ignore for the moment being, add a TODO
  item

Fix bugprone-implicit-widening-of-multiplication-result warnings,
though, that's doable and they seem to make sense.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/tap.c b/tap.c
index 34a5705..22db9c5 100644
--- a/tap.c
+++ b/tap.c
@@ -131,7 +131,7 @@ void tap_ip_send(struct ctx *c, struct in6_addr *src, uint8_t proto,
 		memcpy(&iph->saddr, &src->s6_addr[12], 4);
 
 		iph->check = 0;
-		iph->check = csum_unaligned(iph, iph->ihl * 4, 0);
+		iph->check = csum_unaligned(iph, (size_t)iph->ihl * 4, 0);
 
 		memcpy(data, in, len);
 
@@ -337,9 +337,9 @@ resume:
 			continue;
 
 		iph = (struct iphdr *)(eh + 1);
-		if ((iph->ihl * 4) + sizeof(*eh) > len)
+		if ((size_t)iph->ihl * 4 + sizeof(*eh) > len)
 			continue;
-		if (iph->ihl * 4 < (int)sizeof(*iph))
+		if ((size_t)iph->ihl * 4 < (int)sizeof(*iph))
 			continue;
 
 		if (iph->saddr && c->addr4_seen != iph->saddr) {
@@ -347,7 +347,7 @@ resume:
 			proto_update_l2_buf(NULL, NULL, &c->addr4_seen);
 		}
 
-		l4h = (char *)iph + iph->ihl * 4;
+		l4h = (char *)iph + (size_t)iph->ihl * 4;
 		l4_len = len - ((intptr_t)l4h - (intptr_t)eh);
 
 		if (iph->protocol == IPPROTO_ICMP) {