svn commit: r340959 - stable/12/sys/netinet

[Eugene Grosbein]

Author: eugen
Date: Mon Nov 26 12:39:57 2018
New Revision: 340959
URL: https://svnweb.freebsd.org/changeset/base/340959

Log:
  MFC r339808: Prevent ip_input() from panicing due to unprotected access
  to INADDR_HASH.
  
  PR:			220078
  Differential Revision:	https://reviews.freebsd.org/D12457
  Tested-by:		Cassiano Peixoto and others

Modified:
  stable/12/sys/netinet/ip_input.c
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/sys/netinet/ip_input.c
==============================================================================
--- stable/12/sys/netinet/ip_input.c	Mon Nov 26 12:19:30 2018	(r340958)
+++ stable/12/sys/netinet/ip_input.c	Mon Nov 26 12:39:57 2018	(r340959)
@@ -448,6 +448,7 @@ ip_direct_input(struct mbuf *m)
 void
 ip_input(struct mbuf *m)
 {
+	struct rm_priotracker in_ifa_tracker;
 	struct ip *ip = NULL;
 	struct in_ifaddr *ia = NULL;
 	struct ifaddr *ifa;
@@ -681,7 +682,7 @@ passin:
 	/*
 	 * Check for exact addresses in the hash bucket.
 	 */
-	/* IN_IFADDR_RLOCK(); */
+	IN_IFADDR_RLOCK(&in_ifa_tracker);
 	LIST_FOREACH(ia, INADDR_HASH(ip->ip_dst.s_addr), ia_hash) {
 		/*
 		 * If the address matches, verify that the packet
@@ -693,11 +694,11 @@ passin:
 			counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
 			counter_u64_add(ia->ia_ifa.ifa_ibytes,
 			    m->m_pkthdr.len);
-			/* IN_IFADDR_RUNLOCK(); */
+			IN_IFADDR_RUNLOCK(&in_ifa_tracker);
 			goto ours;
 		}
 	}
-	/* IN_IFADDR_RUNLOCK(); */
+	IN_IFADDR_RUNLOCK(&in_ifa_tracker);
 
 	/*
 	 * Check for broadcast addresses.