svn commit: r267969 - head/usr.sbin/bsnmpd/modules/snmp_lm75

[Luiz Otavio O Souza]

Author: loos
Date: Fri Jun 27 18:40:14 2014
New Revision: 267969
URL: http://svnweb.freebsd.org/changeset/base/267969

Log:
  Correct the buffer length check to avoid overflows.
  
  Found with:	Coverity Scan
  CID:		1222502, 1222503

Modified:
  head/usr.sbin/bsnmpd/modules/snmp_lm75/snmp_lm75.c

Modified: head/usr.sbin/bsnmpd/modules/snmp_lm75/snmp_lm75.c
==============================================================================
--- head/usr.sbin/bsnmpd/modules/snmp_lm75/snmp_lm75.c	Fri Jun 27 18:32:20 2014	(r267968)
+++ head/usr.sbin/bsnmpd/modules/snmp_lm75/snmp_lm75.c	Fri Jun 27 18:40:14 2014	(r267969)
@@ -140,7 +140,7 @@ sysctlname(int *oid, int nlen, char *nam
 {
 	int mib[12];
 
-	if (nlen > (int)sizeof(mib) + 2)
+	if (nlen > (int)(sizeof(mib) / sizeof(int) - 2))
 		return (-1);
 
 	mib[0] = 0;
@@ -158,7 +158,7 @@ sysctlgetnext(int *oid, int nlen, int *n
 {
 	int mib[12];
 
-	if (nlen  > (int)sizeof(mib) + 2)
+	if (nlen > (int)(sizeof(mib) / sizeof(int) - 2))
 		return (-1);
 
 	mib[0] = 0;
@@ -180,10 +180,13 @@ update_sensor_sysctl(char *obuf, size_t 
 
 	/* Fill out the mib information. */
 	snprintf(buf, sizeof(buf) - 1, "dev.lm75.%d.%s", idx, name);
-	len = 4;
+	len = sizeof(mib) / sizeof(int);
 	if (sysctlnametomib(buf, mib, &len) == -1)
 		return (-1);
 
+	if (len != 4)
+		return (-1);
+
 	/* Read the sysctl data. */
 	if (sysctl(mib, len, obuf, obuflen, NULL, 0) == -1)
 		return (-1);