CVE-2017-13001/NFS: Don't copy more data than is in the file handle.

[tcpdump] / print-nfs.c

diff --git a/print-nfs.c b/print-nfs.c
index ef64d13ab23e80963a4b4ef32459096197f65091..f3e8666e75f81cfc36b6ade10fbf66ca91af4ef3 100644 (file)
--- a/print-nfs.c
+++ b/print-nfs.c
@@ -807,11 +807,15 @@ nfs_printfh(netdissect_options *ndo,
 
        if (sfsname) {
                /* file system ID is ASCII, not numeric, for this server OS */
-               static char temp[NFSX_V3FHMAX+1];
+               char temp[NFSX_V3FHMAX+1];
+               u_int stringlen;
 
                /* Make sure string is null-terminated */
-               strncpy(temp, sfsname, NFSX_V3FHMAX);
-               temp[sizeof(temp) - 1] = '\0';
+               stringlen = len;
+               if (stringlen > NFSX_V3FHMAX)
+                       stringlen = NFSX_V3FHMAX;
+               strncpy(temp, sfsname, stringlen);
+               temp[stringlen] = '\0';
                /* Remove trailing spaces */
                spacep = strchr(temp, ' ');
                if (spacep)