libpcap should print an error on wrong IPv4 address

0004-invalid-ipv4.patch

@@ -0,0 +1,65 @@
+From 907070918d5e81a515315b395f334e52589fe0fb Mon Sep 17 00:00:00 2001
+From: Guy Harris <guy@alum.mit.edu>
+Date: Wed, 18 Dec 2019 15:06:53 -0800
+Subject: [PATCH] Check for invalid IPv4 addresses.
+
+This should fix GitHub issue #893.
+---
+ gencode.c    | 9 ++++++++-
+ nametoaddr.c | 9 ++++++++-
+ 2 files changed, 16 insertions(+), 2 deletions(-)
+
+diff --git a/gencode.c b/gencode.c
+index bdc35e646..040a55315 100644
+--- a/gencode.c
++++ b/gencode.c
+@@ -6947,11 +6947,15 @@ gen_mcode(compiler_state_t *cstate, const char *s1, const char *s2,
+ 		return (NULL);
+ 
+ 	nlen = __pcap_atoin(s1, &n);
++	if (nlen < 0)
++		bpf_error(cstate, "invalid IPv4 address '%s'", s1);
+ 	/* Promote short ipaddr */
+ 	n <<= 32 - nlen;
+ 
+ 	if (s2 != NULL) {
+ 		mlen = __pcap_atoin(s2, &m);
++		if (mlen < 0)
++			bpf_error(cstate, "invalid IPv4 address '%s'", s2);
+ 		/* Promote short ipaddr */
+ 		m <<= 32 - mlen;
+ 		if ((n & ~m) != 0)
+@@ -7009,8 +7013,11 @@ gen_ncode(compiler_state_t *cstate, const char *s, bpf_u_int32 v, struct qual q)
+ 		vlen = __pcap_atodn(s, &v);
+ 		if (vlen == 0)
+ 			bpf_error(cstate, "malformed decnet address '%s'", s);
+-	} else
++	} else {
+ 		vlen = __pcap_atoin(s, &v);
++		if (vlen < 0)
++			bpf_error(cstate, "invalid IPv4 address '%s'", s);
++	}
+ 
+ 	switch (q.addr) {
+ 
+diff --git a/nametoaddr.c b/nametoaddr.c
+index 53070a285..13bf4c683 100644
+--- a/nametoaddr.c
++++ b/nametoaddr.c
+@@ -674,8 +674,15 @@ __pcap_atoin(const char *s, bpf_u_int32 *addr)
+ 	len = 0;
+ 	for (;;) {
+ 		n = 0;
+-		while (*s && *s != '.')
++		while (*s && *s != '.') {
++			if (n > 25) {
++				/* The result will be > 255 */
++				return -1;
++			}
+ 			n = n * 10 + *s++ - '0';
++		}
++		if (n > 255)
++			return -1;
+ 		*addr <<= 8;
+ 		*addr |= n & 0xff;
+ 		len += 8;

libpcap.spec

@@ -1,7 +1,7 @@
 Name:     libpcap
 Epoch:    14
 Version:  1.9.1
-Release:  2%{?dist}
+Release:  3%{?dist}
 Summary:  A system-independent interface for user-level packet capture
 License:  BSD with advertising
 URL:      http://www.tcpdump.org
@@ -18,6 +18,7 @@ Source:  http://www.tcpdump.org/release/%{name}-%{version}.tar.gz
 Patch0001:      0001-man-tcpdump-and-tcpslice-have-manpages-in-man8.patch
 Patch0002:      0002-pcap-config-mitigate-multilib-conflict.patch
 Patch0003:      0003-pcap-linux-apparently-ctc-interfaces-on-s390-has-eth.patch
+Patch0004:      0004-invalid-ipv4.patch
 
 %description
 Libpcap provides a portable framework for low-level network
@@ -83,6 +84,9 @@ rm -f $RPM_BUILD_ROOT%{_libdir}/libpcap.a
 %{_mandir}/man5/pcap*.5*
 
 %changelog
+* Mon Feb 24 2020 Michal Ruprich <mruprich@redhat.com> - 14:1.9.1-3
+- libpcap should print an error on wrong IPv4 address
+
 * Wed Jan 29 2020 Fedora Release Engineering <releng@fedoraproject.org> - 14:1.9.1-2
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_32_Mass_Rebuild