svn commit: r342228 - stable/12/libexec/bootpd

[Ed Maste]

Author: emaste
Date: Wed Dec 19 18:17:59 2018
New Revision: 342228
URL: https://svnweb.freebsd.org/changeset/base/342228

Log:
  MFC r342227: bootpd: validate hardware type
  
  Due to insufficient validation of network-provided data it may have been
  possible for a malicious actor to craft a bootp packet which could cause
  a stack buffer overflow.
  
  admbugs:	850
  Reported by:	Reno Robert
  Reviewed by:	markj
  Approved by:	so
  Security:	FreeBSD-SA-18:15.bootpd
  Sponsored by:	The FreeBSD Foundation

Modified:
  stable/12/libexec/bootpd/bootpd.c
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/libexec/bootpd/bootpd.c
==============================================================================
--- stable/12/libexec/bootpd/bootpd.c	Wed Dec 19 18:16:29 2018	(r342227)
+++ stable/12/libexec/bootpd/bootpd.c	Wed Dec 19 18:17:59 2018	(r342228)
@@ -636,6 +636,10 @@ handle_request()
 	char *homedir, *bootfile;
 	int n;
 
+	if (bp->bp_htype >= hwinfocnt) {
+		report(LOG_NOTICE, "bad hw addr type %u", bp->bp_htype);
+		return;
+	}
 	bp->bp_file[sizeof(bp->bp_file)-1] = '\0';
 
 	/* XXX - SLIP init: Set bp_ciaddr = recv_addr here? */